Thematic list of TAR articles

AUTORTYTUŁKATEGORIAABSTRAKTSŁOWA KLUCZOWEROKVOLISSUESTRONYDOITYTUŁ CZASOPISMA
Ewelina Kluska, Piotr Gruda, Natalia Majca-NowakStrain optical analysis of 3d printing elements in different additive technologies in comparison with the finite element method3D printingResearch included in this article were conducted with a project: ‘Additive technology used in conduction with optical methods for rapid prototyping of 3D printed models’. In this article intellectualized three various 3D printing technologies: Fused Deposition Modelling (FDM), Selective Laser Sintering (SLS) and Material Jetting (PolyJet). Also, there was presented theory of Digital Image Correlation (DIC) as an optical method for strain analysis. The limitations of DIC system have been tested and detected. The test result for DIC system were shown for each method of additive technologies and the results were compared to Finite Element Method (FEM). Test specimens were printed in selected technologies for reference. DIC system has been used for displacement state in loaded objects. The last paragraph contains both summary and tests results. Additive technology
3D printing
digital image correlation
finite element method
2018325249-6810.2478/TAR-2018-0022Transactions on Aerospace Research
Ewelina Kluska, Piotr Gruda, Natalia Majca-NowakThe accuracy and the printing resolution comparison of different 3D printing technologies3D printingThe article presents a research conducted with the project: ‘Additive technology used in conduction with optical methods for rapid prototyping of 3D printed models’ [13]. In this article selected three different 3D printing technologies: Fused Deposition Modeling (FDM), Selective Laser Sintering (SLS) and Material Jetting (MJ). Each of them was tested paying special attention to accuracy and resolution of printed elements. Accuracy tests were conducted on the reference specimens which also showed material texture. These specimens were scanned to verified dimensional deviations of printing methods. Printing resolution was verified on a heat exchanger model which was characterized by complicated structure. The highest accuracy and printing resolution was noticed in the MJ technology, PolyJet method on the Objet Eden 260 VS printing machine and the SUP 707 water soluble support material. 3D printing
accuracy
printing resolution
complicated shapes
2018325269-8610.2478/TAR-2018-0023Transactions on Aerospace Research
Sławomir Cieślak, Wiesław Krzymień, Krzysztof SzafranAcoustic Characteristics of the Cabin of the Research Platform on the Airbag IL-PRC-600MAcousticsHovercrafts are a universal means of transport intended for use on flat surfaces such as water, ice, snow, swamp, or sand. They are used in rescue operations and patrolling difficult areas inaccessible to other means of transport. The Institute of Aviation conducted acoustic measurements inside the cabin of the hovercraft to determine the source of the noise and the sound pressure exerted on the pilot and passengers. Assessment of the sources of noise in the cabin is made using the acoustic beamforming method. Assessment of the level of noise to which a pilot is exposed during the operation was prepared on the basis of a standard specifying the requirements and methods of determining occupational noise exposure [1]. noise
acoustics
acoustic
beamforming
hovercraft
cabin
2018225116-2310.2478/TAR-2018-0012Transactions on Aerospace Research
Sławomir Cieślak, Wiesław KrzymieńDrivetrain Noise of the Gyroplane I-28AcousticsGyroplanes, as ultralight aircraft, are popular transport vehicles recently. Ultralight aircraft flights take place at a low altitude – their noise is not without effect on people and nature. The localization of the sources of noise and a possibility to decrease the noise of an gyroplane are described in this paper. The rules of design and exploitation of gyroplanes do not define the limits of emitted noise. gyroplane
noise
acoustic camera
beamforming
propeller noise
201812507-1610.2478/TAR-2018-0001Transactions on Aerospace Research
Ohlenforst Barbara, Ligthart Seth, Aalmoes Roalt, Dirk Schreckenberg and Maykel van MiltenburgAssociation between short-term annoyance and several physiological parameters during different amounts of nocturnal aircraft noise exposure.AcousticsAnnoyance is the most prevalent community response to environmental noise. Observational and experimental lab studies have shown that exposure to environmental noise leads to annoyance, sleep disturbance, daytime sleepiness, increased heart rate and increased blood pressure. However, previous literature is preliminary based on controlled settings or experimental design, raising the question of
the generalizability and applicability in daily life scenarios. This study aimed to investigate two main research questions. First, what is the relationship between short-term annoyance and different amounts of nocturnal aircraft noise exposure in daily life? Second, what is the relationship between physiological parameters, including heart rate, number of awakenings, sleep efficiency, sleep duration and different amounts of nocturnal aircraft noise exposure in daily life? This study also aimed to explore the suitability of non-invasive commercially available activity trackers to measure physiological metrics in a scientific way. During this field study, participants were wearing Fitbit Charge 3 activity trackers recording heart rate and different sleep-derived metrics (e.g. deep sleep duration, sleep efficiency and awakenings).
The used activity trackers were readily available, non-intrusive, relatively cheap and easy to use by
the participants. Simultaneously, a logbook was used by the participants to track the subjective perception and situational context of air traffic noise exposure. The noise levels corresponding to the exposure of air traffic of each participant were calculated based on the location of the participant and the corresponding radar track using an aircraft noise monitoring system.
We hypothesize that a higher amount of exposure to aircraft noise in real life will be associated with increased annoyance, increased rest heartrate, higher number of awakenings, decreased sleep efficiency and decreased deep sleep duration.
Preliminary results on the interactions between aircraft noise exposure, perceived annoyance and physiological metrics suggest increased nocturnal aircraft noise exposure seems to negatively affect sleep efficiency and deep sleep duration.
Aviation,
aircraft noise,
short-term annoyance,
heart rate,
deep sleep,
sleep efficiency,
awakenings,
actigraphy.
202042611-1210.2478/TAR-2020-0018Transactions on Aerospace Research
Michał Gęca, Konrad Pietrykowski, Karol RosińskiThe Research of Acoustic Emission of a Low-Power Aircraft EngineAcousticsThis paper presents the methodology and investigation of the sound power level produced by a radial piston aircraft engine operating at varied speeds. The research model aircraft engine of a maximum power of 5.5 kW with a two-bladed airscrew was placed on a test bend. Its sound power level was calculated from the sound pressure level measured at 9 measurement points distributed on a hemispherical surface in a confined space in line with PN-EN 3744. Mean sound power generated by the ASP FS400AR engine is 96 dB at idle (2,880 rpm) and 105 dB at a cruising speed (4,740 rpm). Accordingly, it can be concluded that a sound level meter registered a higher sound power level at the points in front of the model aircraft engine than at the points behind it, whereas the lowest sound power level was registered directly above the engine. model aircraft engine
aerospace propulsion systems
sound power
noise
2018325214-2510.2478/TAR-2018-0019Transactions on Aerospace Research
Ewelina Kluska, Piotr Gruda, Natalia Majca-NowakStrain optical analysis of 3d printing elements in different additive technologies in comparison with the finite element methodAdditive manufacrturingResearch included in this article were conducted with a project: ‘Additive technology used in conduction with optical methods for rapid prototyping of 3D printed models’. In this article intellectualized three various 3D printing technologies: Fused Deposition Modelling (FDM), Selective Laser Sintering (SLS) and Material Jetting (PolyJet). Also, there was presented theory of Digital Image Correlation (DIC) as an optical method for strain analysis. The limitations of DIC system have been tested and detected. The test result for DIC system were shown for each method of additive technologies and the results were compared to Finite Element Method (FEM). Test specimens were printed in selected technologies for reference. DIC system has been used for displacement state in loaded objects. The last paragraph contains both summary and tests results. Additive technology
3D printing
digital image correlation
finite element method
2018325249-6810.2478/TAR-2018-0022Transactions on Aerospace Research
Ewelina Kluska, Piotr Gruda, Natalia Majca-NowakThe accuracy and the printing resolution comparison of different 3D printing technologiesAdditive manufacrturingThe article presents a research conducted with the project: ‘Additive technology used in conduction with optical methods for rapid prototyping of 3D printed models’ [13]. In this article selected three different 3D printing technologies: Fused Deposition Modeling (FDM), Selective Laser Sintering (SLS) and Material Jetting (MJ). Each of them was tested paying special attention to accuracy and resolution of printed elements. Accuracy tests were conducted on the reference specimens which also showed material texture. These specimens were scanned to verified dimensional deviations of printing methods. Printing resolution was verified on a heat exchanger model which was characterized by complicated structure. The highest accuracy and printing resolution was noticed in the MJ technology, PolyJet method on the Objet Eden 260 VS printing machine and the SUP 707 water soluble support material. 3D printing
accuracy
printing resolution
complicated shapes
2018325269-8610.2478/TAR-2018-0023Transactions on Aerospace Research
Natalia Majca-Nowak, Ewelina Kluska, Piotr GrudaComparative analysis of macro- and microstructure of printed elements in the FDM, SLS and MJ technologiesAdditive manufacturingThe article presents research conducted with the project: ‘Additive manufacturing in conduction with optical methods used for optimization of 3D models’’ [2]. The article begins with the description of properties of the materials used in three different additive technologies – Fused Deposition Modelling (FDM), Selective Laser Sintering (SLS) and Material Jetting (MJ). The next part focuses on
the comparative analysis of macro- and microstructure of specimens printed in order to test selected materials in additive technologies mentioned above. In this research two types of specimens were used: dumbbell specimens and rectangular prism with hole specimens. In order to observe macrostructure specimens, they were subjected to load test until it broke. In the case of observing microstructure, they were cut in some places. Each of described additive technologies characterizes by both different way of printing and used materials. These variables have a significant influence on macro- and microstructure and fracture appearance. FDM technology specimens printed of ABS material characterized by texture surface appearance. SLS technology specimens printed of PA12 material characterized by amorphous structure. MJ technology specimens printed of VeroWhite Plus material characterized by fracture appearance which had quasi- fatigue features. The microstructure of these specimens was uniform with visible inclusions.
additive manufacturing,
3D printing,
macrostructure,
microstructure,
FDM,
SLS,
MJ,
PolyJet
2019425766-8010.2478/TAR-2019-0024Transactions on Aerospace Research
Maciej KarnyON THE AREOSPACE-GRADE ADHESIVES SHEAR STRENGTH TESTING WITH ASTM D5656 TEST AS AN EXAMPLEAdhesive bondingThis article presents adhesive shearing test methods, focusing especially on the ASTM D5656 method. These methods will be briefly characterized and compared. The most important concerns about the D5656 method are described. With the use of ASTM D1002 and D5656 methods, the influence of adherend surface preparation on shearing properties of the bond is evaluated. Compared to sandblasting only, sandblasting followed by the FPL process (sulfochromate etching of aluminum) increased shear strength of joints by 35 % for ASTM D1002 tests and by 48% for D5656 tests. Comparing these two methods, shear strength obtained in D5656 tests is about two times higher than in D1002 tests. The cause for this phenomena is much larger adherend thickness in the D5656 method, which provides the coupons with increased stiffness. Shear modulus, calculated with 3 different calculation methods, showed differences in obtained results, which points to necessary actualization of D5656 standard. adhesives
shear modulus
ASTM D5656
shear strength
2019225533-4310.2478/TAR-2019-0008Transactions on Aerospace Research
Igor F. Kravchenko, Vasyl V. Loginov, Yevgene O. Ukrainets and Pavlo A. HlushchenkoAerodynamic characteristics of a straight wing with a spiroid wingtip device.AerodynamicsSpiroid wingtip devices (WD) offer a promising way of improving the lift drag ratio of UAVs, but may on the other hand lead to negative aerodynamic interference of the wing with the WD and deterioration of the aerodynamic characteristics as compared to a wing without the WD. Determining the influence of the geometric parameters of a spiroid WD on aerodynamic wing characteristics, however, remains an understudied field. In our study, we investigated the influence of the following geometrical parameters on wing aerodynamic characteristics with WD: area, radius, camber angle, constriction, and pitch of the spiroid. We found that the positive effect of the WD is present at a relative radius > 0.05, as well as with an increase in the lift coefficient CL as a result of an increase in the proportion of inductive resistance. For example, with the Reynolds number Re = 2.1×105 for a rectangular wing with an aspect ratio θ = 5.12 equipped with a spiroid WD with =0.15 the quality gain is almost 10% at CL = 0.5, and at CL = 0.7 is almost 20% and at CL = 0.7 – almost 20% compared to a wing without WD. Moreover, we found that a change in the camber angle WD θ provides an increase in the derivative of the lift coefficient with respect to the angle of attack in the range from θ = 0° to θ = 130°. By changing the camber angle, it is possible to increase the lift drag ratio of the layout up to 7.5% at θ = 90° compared to θ = 0° at the Reynolds number Re = 2.1×105. From the point of view of ensuring maximum lift drag ratio and minimum inductive drag, the angle θ = 90° is the most beneficial. lift drag ratio
flight range
flight duration
unmanned aerial vehicles
aerodynamic configuration
spiroid wingtip devices
2021226346-6210.2478/TAR-2021-0010Transactions on Aerospace Research
Adam DziubińskiCFD Analysis of The Tractor Propulsion Concepts for an Inverted Joined Wing AirplaneAerodynamicsEfficiency is a crucial parameter for an airplane to reduce both cost of operations and emission of pollutants. There are several airplane concepts that potentially allow for increasing the efficiency. A few of them were not investigated thoroughly enough yet. The inverted joined wing configuration, with the upper wing in front of the lower one is an example of such concept. Therefore, a project consisting
of development of an experimental scaled demonstrator, and its wind tunnel and flight testing, was undertaken by consortium: Institute of Aviation, Warsaw University of Technology, Air Force Institute of Technology and a MSP company. Results led to a conclusion, that the inverted joined wing configuration allows to build an airplane with excellent performance, but its advantage against
the conventional airplane is marginal because of large trimming drag of the configuration with relatively high position of the thrust vector in pusher configuration. It was applied because the demonstrator was a flying model of manned airplane and the tractor configuration would affect the pilot’s field
of observation. However, in case of the UAV, this reason becomes insignificant. Therefore two configurations of tractor propulsion were tested to see, if their performance is better than the performance of original design.
CFD,
joined wing,
tractor propulsion.
2020225913-2610.2478/TAR-2020-0007Transactions on Aerospace Research
Austin M. Karr, Wit StryczniewiczESTIMATION OF AN AIRFOIL DRAG AT HIGH ANGLES OF ATTACK FROM PIV DATAAerodynamicsThe paper presents application of Particle Image Velocimetry for determination of an airfoil’s drag coefficient in wind tunnel tests. The purpose of the study was to investigate the feasibility of using PIV as an alternative to pressure rake measurements, especially at high angles of attack. The integral momentum concept was applied for determination of fluid drag from experimental low speed wind tunnel data. The drag coefficient was calculated from velocity and pressure rake data for intermediate angles of attack from 5° to 10°. Additionally, the experimental results were compared to panel method results. After validating the procedures at low angles of attack, the drag coefficient was calculated at close to critical angles of attack. The presented study proved that PIV technique can be considered as an attractive alternative for drag coefficient determination of an airfoil. fluid drag
wind tunnel tests
high angles of attack
Particle Image Velocimetry
2019125428-3610.2478/TAR-2019-0003Transactions on Aerospace Research
Stanisław Popowski, Witold DąbrowskiAnalysis of Methods Used to Eliminate the Propeller Slipstream Effect in Single-Engine AircraftAerodynamicsPropeller-driven single-engine aircraft are affected by unsymmetrical flow of air around the fuse-lage, and especially around the vertical stabilizer [1-3]. This unsymmetrical, propeller-induced slip-stream produces sideslip [4,5] that needs to be compensated by the pilot using the rudder [6]. In order to relieve the pilot from this additional task, automatic rudder deflection systems are used that compensate for sideslip by trimming the rudder accordingly. Such compensation algorithms are based on flight parameter measurements. single-engine aircraft
propeller slipstream
sideslip angle
2018225151-5910.2478/TAR-2018-0015Transactions on Aerospace Research
Paweł Ruchała, Robert Placek, Wit Stryczniewicz, Jan Matyszewski, Dawid Cieśliński, Bartosz BartkowiakWind Tunnel Tests of Influence of Boosters and Fins on Aerodynamic Characteristics of the Experimental Rocket PlatformAerodynamicsThe paper presents results of wind tunnel tests of the Experimental Rocket Platform (ERP), which is developed in Institute of Aviation. It is designed as an easy accessible and affordable platform for microgravity experiments. Proposed design enables to perform experiments in microgravity for almost 150 seconds with apogee of about 100 km. Aerodynamics of rocket
flight mechanics of rocket
wind tunnel tests
experimental
rocket
platform
ERP
sounding rocket
2017424982-10210.2478/TAR-2017-0030Transactions on Aerospace Research
Daniel Filipiak, Robert Szczepaniak, Tomasz Zahorski, Robert Bąbel, Sebastian Stabryn, Wit StryczniewiczFlow visualization over an airfoil with flight control surfaces in a water tunnelAerodynamicsThis paper demonstrates the feasibility of using-a water tunnel for the visualisation of flow in airfoils with flight control systems in the form of slots and flaps. Furthermore, the issue of using water tunnels for scientific and training purposes was explained. The technology of 3D printed models for practical tests in a water tunnel was also presented. The experiment included conducting flow visualisation tests for three airfoil models: with the Clark Y 11.7% as the base airfoil and the same airfoil with a slot and a flap. Moreover, a modification to dye injection system was introduced. The presented results of flow visualisation around models with the use of dye, confirmed the effectiveness of the applied methodology. The results and conclusions may be utilized to verify most flow-related issues in hydrodynamic tunnels and can also be used as a training element. water tunnel testing
airfoil
flaps
slots
2017124663-7810.2478/TAR-2017-0007Transactions on Aerospace Research
Jan Muchowski, Marek Szumski, Andrzej KrzysiakAerodynamic Concept of the UAV in the Gyrodyne ConfigurationAerodynamicsThe article presents an aerodynamic concept of UAV in the gyrodyne configuration, as a more efficient one than the currently used UAV airframe configuration applied for monitoring tasks of power lines and railway infrastructure. A sample task which is realised by conceptual gyrodyne based on monitoring aerial power lines was characterised and described. The assumed idea of UAV was shown in comparison to the currently used aircraft configuration presented in the introduction. Referring to momentum theory, hover efficiency of the multicopter and the helicopter was evaluated. In relation to the helicopter, an initial draft of the airframe conception accompanied by a description of advantages of the gyrodyne configuration was exposed. Problems related to the gyrodyne configuration were emphasised in the summary. aerodynamic concept
UAV
VTOL
gyrodyne
airframe configuration
2018125049-6610.2478/TAR-2018-0005Transactions on Aerospace Research
Robert S. RowińskiMATHEMATICAL MODEL SAND COMPUTER SIMULATIONS OF AERIAL SPRAYINGAND DROPLETS DISTRIBUTION IN A TARGET SITEAerodynamicsMathematical models describing aerial spraying and the distribution of liquid droplets on a target were presented. Relationships based on “free models” with Gaussian distribution of droplet concentrations and “bound models” that account for the impact of disturbances in the velocity field behind agricultural aircraft were expanded, and the hybrid model too. The results of experimental studies were presented and compared with theoretical calculations. The “bound model” was found to be the most effective solution for describing the physical phenomena that accompany the aerial spraying process. agricultural aviation
aerial spraying
drift
2019325624-4210.2478/TAR-2019-0015Transactions on Aerospace Research
Tomasz Seredyn, Adam Dziubiński, Piotr JaśkowskiCFD Analysis of the Fluid Particles Distribution by Means of Aviation TechniqueAerodynamicsThe article describes a computational study, using CFD models, of droplet spray dispersal in the wake of a ‘Turbo Kruk’ airplane up to 500 m downstream. The CFD Reynolds-averaged Navier-Stokes (RANS) models use a Lagrangian (droplet phase) and Eulerian (fluid phase) procedure to predict the droplet trajectories trough the turbulent aircraft wake. The methods described in the work have the potential to improve current models for aerial spraying and will help in the development of new spraying procedures. In this study, the CFD models are used to describe the phenomenon of sprays released from atomizers mounted on the plane. A parametric study of the aircraft model examines the effects of crosswind on the aircraft’s vortex structures and the resulting droplet trajectories. The study shows, that such influence is underestimated in the current models. A comparison of the present results to AGDISP predictions is provided. Droplets dispersion modeling
Pesticide spraying
Agricultural aircraft wake
2018125067-9710.2478/TAR-2018-0006Transactions on Aerospace Research
Łukasz Jeziorek, Krzysztof Szafran, Paweł SkalskiHeat Transfer Determined by the Temperature Sensitive Paint MethodAerodynamicsThe paper presents practical aspects of determining the amount of heat flow by measuring the distribution of surface temperature using the Temperature Sensitive Paint (TSP) method. The quantity measured directly with TSP is the intensity of the excited radiation, which is then converted to surface temperature. The article briefly presents three different methods for determining the heat transfer coefficient. Each of these methods is based on a separate set of assumptions and significantly influences the construction of the measuring station. The advantages of each of the presented methods are their individual properties, allowing to improve accuracy, reduce the cost of testing or the possibility of using them in tests of highly complex objects. For each method a mathematical model used to calculate the heat transfer coefficient is presented. For the steady state heat transfer test method that uses a heater of constant and known thermal power, examples of the results of our own research are presented, together with a comparison of the results with available data and a discussion of the accuracy of the results obtained. temperature sensitive paint
TSP
temperature measurement
heat transfer coefficient
HTC
2018425345-5710.2478/TAR-2018-0029Transactions on Aerospace Research
William J. Deitrick, Wit StryczniewiczDevelopment and Testing of Data Reduction Software for Measurements Using Pressure Sensitive PaintsAerodynamicsThe paper concentrates on post-processing of data necessary for pressure measurements using Pressure Sensitive Paints (PSP). The purpose of the study was to develop and test procedures for extraction of the surface pressure distribution from the images captured during PSP tests. The core issues addressed were reduction of the influence of model movement and deformation during wind tunnel run and synchronization between conventional pressure tap measurements and PSP data, necessary for in-situ calibration. In the course of the studies, two approaches on image registration were proposed: the first based on geometric transformation of control points pairs with cross-correlation tuning and the second based on similarity finding and estimation of geometric transformation of the images. Performance of the developed algorithm was tested with use of experimental set-up allowing for controlled movement of the imagined target with micrometer resolution. Both of the proposed approaches to PSP image resection proved to perform well. After testing of the software, the PSP system was used for determination of the pressure field on flat plate exposed to impinging jet. The presented procedures and results can be useful for research groups developing in-house PSP measurements systems for wind tunnel tests and internal flow investigations. Pressure Sensitive Paint
image registration
impinging jet
2018425368-8010.2478/TAR-2018-0031Transactions on Aerospace Research
Łukasz Jeziorek, Patryk WideraTemperature measurements using thermal sensitive paintAerodynamicsArticle highlights practical issues concerning temperature measurements using thermal sensitive paint (abbrev. TSP). TSP paint after blue light excitation emits red light with intensity dependent on its temperature. Temperature measurements are preceded with paint calibration, according to exact experiment conditions. Purpose of calibration is to find transfer function between intensity of emitted radiation and surface temperature. To achieve this goal, special computational procedure is implemented. Devices and methodology used for paint calibration are briefly described as well as measuring sample preparation process. Short description is devoted to the procedure for calculation temperature using recorded intensity. Results obtained during calibration are presented. Final conclusions about perspective of using thermal sensitive paint in laboratory are presented, as well as advantages and disadvantages of TSP method versus other methods currently used in temperature measurements. Thermal sensitive paint
TSP
temperature measurement
2018325237-4810.2478/TAR-2018-0021Transactions on Aerospace Research
Łukasz KędzierskiCompressed Air Supply and Distribution System for Aviation Laboratories and Wind TunnelsAerodynamicsThe purpose of this text is to demonstrate an operation of a compressed air system designed for high air flow laboratories and wind tunnels. Development of such air system is a challenge due to unusual requirements (simultaneous supply of several users having different requirements and necessity to provide extremely high flows) which have to be address by means of adequate compressed air storage capacity and sophisticated control system. Each stage of the design process is going to be described, focusing on the selection of air compressors, air receivers and air dryers, followed by an insight into a development of the control system. The air system being described in this paper was successfully implemented at the Institute of Aviation in Warsaw improving the quality of the compressed air supply and simplifying the research planning. compressed
air
laboratory
wind
tunnel
2018125026-3510.2478/TAR-2018-0003Transactions on Aerospace Research
Wit StryczniewiczQuantitative Visualisation of Compressible FlowsAerodynamicsThe paper demonstrates the feasibility of quantitative flow visualisation methods for investigation of transonic and supersonic flows. Two methods and their application for retrieving compressible flow field properties has been described: Background Oriented Schlieren (BOS) and Particle Image Velocimetry (PIV). Recently introduced BOS technique extends the capabilities of classical Schlieren technique by use of digital image processing and allow to measure density gradients field. In the presented paper a review of applications of BOS technique has been presented. The PIV is well established technique for whole field velocity measurements. This paper presents application of PIV for determination of the shock wave position above airfoil in transonic flow regime. The study showed that application of quantitative flow visualisation techniques allows to gain new insights on the complex phenomenon of supersonic and transonic flow over airfoils like shock-boundary layer interaction and shock induced flow separation. compressible fluid flow
flow visualisation
wind tunnel studies
Particle Image Velocimetry
Background Oriented Schlieren
20181250137-14510.2478/TAR-2018-0009Transactions on Aerospace Research
Wieńczysław StalewskiFlow Control on Helicopter – Rotor Blades via Active Gurney FlapAerodynamicsThe Active Gurney Flap (AGF) is a small, flat tab cyclically deployed and retracted at lower surface of the rotor blade near its trailing edge. It is expected that the device may improve performance of modern helicopters. The main goal of presented investigations was to develop research methodology and next to use it in studies on phenomena occurring in the flow around helicopter-rotor blades equipped with AGF. Conducted CFD simulations aimed at validation of the developed methodology as well as at significant supplementing and extension of results of experimental research. Simplified sensitivity analysis has been conducted aiming at determination of geometric and motion-control parameters of the AGF, optimal from point of view of helicopter-performance improvement. Fully three-dimensional simulations of the rotor flight aimed at determination of flight conditions, in which the use of Active Gurney Flaps could significantly improve the rotorcraft performance. helicopter rotor blades
active flow control
Active Gurney Flap
rotorcraft performance
2018125098-11810.2478/TAR-2018-0007Transactions on Aerospace Research
Ruben Di Batista, Maria Teresa Scelzo, Maria Rosaria VetranoNUMERICAL STUDY OF AN ISOTHERMAL SLUSH FLOW FOR AEROSPACE PROPULSION APPLICATIONSAerodynamicsSlushes are two-phase solid-liquid single-species cryogenic fluids that exhibit an increased density and a greater heat capacity with respect to the corresponding normal boiling point liquids. These promising features are of large interest for applications that exploit slush as a thermal fluid, like super magnets refrigeration, cryogenic cooling of bio-materials or air conditioning, and for aerospace systems that use slush fluids as fuel or oxidizer. Several programs in the frame of the research on Slush Hydrogen (SLH2) as a new-generation fuel for aerospace propulsion have been started in the past. This work was carried out in the framework of a VKI research activity promoted by the Predict ESA Technology Research Programme, to investigate experimentally and numerically the behavior of slush flows in a representative upper stage feeding line. In this paper, we present a simulation based on a granular two-fluid model on an isothermal solid liquid mixture (slurry) and a Nitrogen slush (SLN2) fluid flowing in a horizontal pipe. A finite-volumes discretization using the software library OpenFOAM was benchmarked against experimental and numerical literature data, to assess the accuracy of the code in predicting pressure drops along the pipe axis and solid particle distribution across the pipe diameter. Moreover, the effects of concentration and inlet velocity are investigated. We show that the numerical model fairly reproduces the literature data in terms of important aspects as the solid volume fraction distribution and the pressure drops, especially for high flow rates. fluid dynamics
space propulsion
multiphase flows
CFD
cryogenics
slush flows
2019225582-9510.2478/TAR-2019-0011Transactions on Aerospace Research
Wojciech KoniorParticle-in-cell Electrostatic Numerical AlgorithmAerodynamicsExisting global models of interaction between the solar wind (SW) and the local interstellar medium (LISM) describe the heliosphere that arises as a result of this interaction. There is a strong motivation to develop a kinetic model using the Particle-in-Cell (PIC) method to describe phenomena which appear in the heliosphere. This is however a long term scientific goal. This paper describes an electrostatic Particle-in-Cell numerical model developed in the Institute of Aviation in Warsaw, which includes mechanical and charge exchange collisions between particles in the probabilistic manner using Direct Simulation Monte Carlo method. This is the first step into developing simulations of the heliosphere incorporating kinetic effects in collisionless plasmas. In this paper we focus only on presenting the work, which have been done on the numerical PIC algorithm. plasma
neutral particles
Particle-in-Cell
Monte-Carlo Method
2017324824-4510.2478/TAR-2017-0020Transactions on Aerospace Research
Marek Idzikowski, Wojciech MiksaGround and In-Fligh Testing of Cooling Efficiency of Turboprop Engine CompartmentAerodynamicsThis article presents selected results of I-31T propulsion tests, obtained in the framework of EU project ESPOSA (Efficient Systems and Propulsion for Small Aircraft). I-31T aircraft, as a testbed, was fitted with 180 kW turboprop engine TP100. The scope of the work include results of ground and in-flight tests of engine compartment cooling suitability. The purpose of the cooling tests was to prove that temperatures of the propulsion components are within limits set by the engine manufacturer for the engine type in the most disadvantageous conditions on the ground and in flight up to aircraft maximum altitude, maximum ambient temperature and after standard engine shutdown. Engine oil cooling is beyond the scope of this work. light aircraft
in-flight tests
turboprop engine installation
turboprop engine integration in airframe
engine compartment cooling
2018125017-2510.2478/TAR-2018-0002Transactions on Aerospace Research
Maciej KarnyON THE AREOSPACE-GRADE ADHESIVES SHEAR STRENGTH TESTING WITH ASTM D5656 TEST AS AN EXAMPLEAerospace structuresThis article presents adhesive shearing test methods, focusing especially on the ASTM D5656 method. These methods will be briefly characterized and compared. The most important concerns about the D5656 method are described. With the use of ASTM D1002 and D5656 methods, the influence of adherend surface preparation on shearing properties of the bond is evaluated. Compared to sandblasting only, sandblasting followed by the FPL process (sulfochromate etching of aluminum) increased shear strength of joints by 35 % for ASTM D1002 tests and by 48% for D5656 tests. Comparing these two methods, shear strength obtained in D5656 tests is about two times higher than in D1002 tests. The cause for this phenomena is much larger adherend thickness in the D5656 method, which provides the coupons with increased stiffness. Shear modulus, calculated with 3 different calculation methods, showed differences in obtained results, which points to necessary actualization of D5656 standard. adhesives
shear modulus
ASTM D5656
shear strength
2019225533-4310.2478/TAR-2019-0008Transactions on Aerospace Research
Goncharenko Andriy ViktorovichTwo entropy theory wings as a new trend for the modern means of air transport operational reliability measure.Air transportationThe paper deals with the uncertainty of the operated system’s possible states hybrid combined optional functions. Traditionally, the probabilities of the system’s possible states are treated as the reliability measures. However, in the framework of the proposed doctrine, the optimality (for example, the maximal probability of the system’s state) is determined based upon a plausible assumption of the intrinsic objectively existing parameters. The two entropy theory wings consider on one hand the subjective preferences functions in subjective analysis, concerning the multi-alternativeness of the operational situation at an individual’s choice problems, and on the other hand the objectively existing characteristics used in theoretical physics. The discussed in the paper entropy paradigm proceeds with the objectively presented phenomena of the state’s probability and the probability’s maximum. The theoretical speculations and mathematical derivations are illustrated with the necessary plotted diagrams.entropy,
preference,
option,
optimization,
probability,
maximum,
alternative,
functional,
condition
2020326064-7410.2478/TAR-2020-0017Transactions on Aerospace Research
Dawid ZaduraImportance of personal data protection law for commercial air transportAir transportationIn the review below the author presents a general overview of the selected contemporary legal issues related to the present growth of the aviation industry and the development of aviation technologies. The review is focused on the questions at the intersection of aviation law and personal data protection law. Massive processing of passenger data (Passenger Name Record, PNR) in IT systems is a daily activity for the contemporary aviation industry. Simultaneously, since the mid- 1990s we can observe the rapid growth of personal data protection law as a very new branch of the law. The importance of this new branch of the law for the aviation industry is however still questionable and unclear. This article includes the summary of the author’s own research conducted between 2011 and 2017, in particular his audits in LOT Polish Airlines (June 2011-April 2013) and Lublin Airport (July - September 2013) and the author’s analyses of public information shared by International Civil Aviation Organization (ICAO), International Air Transport Association (IATA), Association of European Airlines (AEA), Civil Aviation Authority (ULC) and (GIODO). The purpose of the author’s research was to determine the applicability of the implementation of technical and organizational measures established by personal data protection law in aviation industry entities. aviation industry
aviation law
aviation security
2017124635-4410.2478/TAR-2017-0004Transactions on Aerospace Research
Wojciech G. MiksaAir taxi flight sharing.AIR TRANSPORTATIONIn traditional air taxi model, flight route and timing are assigned to every order individually, resulting in minimum utilization of seats, maximum number of empty legs and elevated price levels. Sharing flights, when possible, allow decreasing number of empty seats and distributing cost of flight among customers. Challenges to overcome are varying timing needs of customers and volatility of demand.
This article investigates possibilities of synchronizing passenger orders. The proposed passenger pooling model replaces specific flight timing on order with constraints: latest arrival and earliest departure to provide room for coordination of orders, backed by web-based ICT. Theoretical test cases calculations verify the concept and compare it with traditional full on-demand and scheduled operations.
air taxi;
service model;
shared service;
load factor
2020326049-6310.2478/TAR-2020-0016Transactions on Aerospace Research
Vasyl Loginov, Oleksandr Grebnikov, Andrii Humennyi, Serhii Eremenko, Oleksandr SobolievPreliminary design for a jet training aircraft.Aircraft designThis paper present the results of our project to develop the preliminary design of a jet trainer plane (JTP) with a two-person crew, the base version of which is intended for cadet training. We first consider the assumptions and requirements for the new aircraft, and review the parameters of existing aircraft designs in the similarly-purposed class. Next we argue for certain design choices, regarding the aircraft layout, cockpit configuration, wing location and wingform, tail scheme, and powerplant. The resulting aircraft design is calculated to have a maximum flight speed of 940 km/h, a ground-level rate of climb of 100 m/s, and a range of 1130 km. The plane’s take-off mass is calculated, in three approximations, at 2264 kg. Lastly we present the training plane’s geometrical parameters, general view, and master geometry. jet trainer plane
performance
take-off mass
scheme
master geometry
2021226330-4510.2478/TAR-2021-0009Transactions on Aerospace Research
František LöffelmannStress Distribution Investigation at the Tapered Sandwich EndingsAircraft designOne of the typical sandwich ending is tapered transition to a solid laminate, which causes significant stress distribution changes. The reviewed articles show that tapered area causes increase in the shear stress in the core, increase of the axial forces in the facesheets and local bending at the fork point, at points of the tapering angle change, and at ply drop positions. Most of the studies gave attention to the endings without reinforcing. During Erasmus+ internship at KTH 2D model of the tapered ending with reinforcing plies, various geometry and resin filler in the core tip was investigated to see the influence on the stress distribution. It was found that tension load case is not as critical as bending load case. Increasing of the solid laminate thickness, adding plies and inserting a short resin or adhesive filler into the core tip area lead to significant stress reduction, whereas in the transition point, from tapering to constant thickness sandwich, increasing radius is more efficient than reinforcing plies in regard to reduce stress concentration. Sandwich endings
Tapering
Ramp
Closeout
FEM
Filler
Ply drop
2017424964-8110.2478/TAR-2017-0029Transactions on Aerospace Research
Georges Bridel, Zdobyslaw Goraj, Lukasz Kiszkowiak, Jean-Georges Brévot, Jean-Pierre Devaux, Cezary SzczepanskiJANUS – A New approach to air combat pilot trainingAircraft designAdvanced jet training still relies on old concepts and solutions that are no longer efficient when considering the current and forthcoming changes in air combat. The cost of those old solutions to develop and maintain combat pilot skills are important, adding even more constraints to the training limitations. The requirement of having a trainer aircraft able to perform also light combat aircraft operational mission is adding unnecessary complexity and cost without any real operational advantages to air combat mission training.
Thanks to emerging technologies, the JANUS project will study the feasibility of a brand-new concept of agile manoeuvrable training aircraft and an integrated training system, able to provide a live, virtual and constructive environment. The JANUS concept is based on a lightweight, low-cost, high energy aircraft associated to a ground based Integrated Training System providing simulated and emulated signals, simulated and real opponents, combined with real-time feedback on pilot’s physiological characteristics: traditionally embedded sensors are replaced with emulated signals, simulated opponents are proposed to the pilot, enabling out of sight engagement. JANUS is also providing new cost effective and more realistic solutions for “Red air aircraft” missions, organised in so-called “Aggressor Squadrons”.
air combat;
advanced training;
red air;
training concept;
innovation;
201942577-2210.2478/TAR-2019-0019Transactions on Aerospace Research
Krzysztof Szafran, Marcin MichalczykVarious Types of the Rotorcraft Design in the Context of Aerospace RegulationsAircraft designIn the next article on synthesis of regulations, the authors presented the general legal requirements for rotorcraft, which is limited to US regulations, because the vast majority of world regulations are based on them. The Institute of Aviation in Warsaw has developed requirements concerning the construction and operation of rotorcraft in Poland. These requirements constitute an important contribution to the regulations of the Civil Aviation Authority which are in force in the air space of the Republic of Poland. This paper presents the legal situation of rotorcraft and compares the requirements for helicopters and gyroplane. The conclusions highlighted the differences that arise from regulations between helicopters and rotorcraft. The authors have suggested the necessity to separate provisions for the group of windmills, which is implemented in the regulations of the Civil Aviation Authority. The presented work is the second of a planned series of publications in which authors intend to bring some of the issues to the reader about the design aspects of aircraft in selected global aviation regulations. aviation regulations
certification
flight safety
helicopters
rotorcraft
gyroplane
20181250146-15310.2478/TAR-2018-0010Transactions on Aerospace Research
Miłosz KalinowskiAero-Structural Optimization of Joined-Wing AircraftAircraft designJoined-wing aircraft due to its energy characteristics is a suitable configuration for electric aircraft when designed properly. However, because of the specific for this aircraft phenomenons (e.g. static indeterminacy of structure, aerodynamic interference of lifting surfaces) it demands more complicated methods to model its behavior than a traditional aircraft configurations. For these reasons the aero-structural optimization process is proposed for joined-wing aircrafts that is suitable for preliminary design. The process is a global search, modular algorithm based on automatic geometry generator, FEM solver and aerodynamic panel method. The range of aircraft was assumed as an objective function. The algorithm was successfully tested on UAV aircraft. The improvement of 19% of total aircraft range is achieved in comparison to baseline aircraft. Time of evaluation of this global search algorithm is similar to the time characteristic for local optimization methods. It allows to reduce the time and costs of preliminary design of joined-wing. Joined-wing
multidyscyplinary optimization
preliminary design
2017424948-6310.2478/TAR-2017-0028Transactions on Aerospace Research
Marco Fioriti, Luca Boggero, Sabrina CorpinoPreliminary Sub-Systems Design Integrated in a Multidisciplinary Design Optimization FrameworkAircraft designThe aircraft design is a complex subject since several and completely different design disciplines are involved in the project. Many efforts are made to harmonize and optimize the design trying to combine all disciplines together at the same level of detail. Within the ongoing AGILE (Horizon 2020) research, an aircraft MDO (Multidisciplinary Design Optimization) process is setting up connecting several design tools and competences together. Each tool covers a different design discipline such as aerodynamics, structure, propulsion and systems. This paper focuses on the integration of the sub-system design discipline with the others in order to obtain a complete and optimized aircraft preliminary design. All design parameters used to integrate the sub-system branch with the others are discussed as for their redefinition within the different detail level of the design. Multidisciplinary Design Optimization
Aircraft Sub-system Design
Design Space Parameters
201742499-2310.2478/TAR-2017-0025Transactions on Aerospace Research
Głowacki Paweł, Kalina Piotr, Kawalec MichałEstimating emissions of harmful exhaust components by aircraft engines during the takeoff and landing cycle in airport space.Aircraft operationsThis article examines, based on the available information and authors’ self-assessments, the environmental impact of turbine engine exhaust gases effect on the environment in the airport space during engines flight phases in the landing and takeoff cycle (LTO). The attention of aviation professionals is drawn to the fact that the amount of exhaust from the turbine engine is so significant that it may adversely change the ambient air at the airport. Consequently, increased emission level of carbon monoxide (CO), hydrocarbons (HC) during engine start-up and idle may pose a threat to the health of ramp staff. Also, high emission levels of nitrogen oxides (NOx) during takeoff, climb, cruise and descent is not without importance for the environment around the airport space. The paper gives CO2, HC, CO and NOx emission estimations based on ICAO Engine Emission Data Bank and the number of passenger operations at a medium-sized airport. It also provides calculation results of aircraft CO2, HC, CO and NOx emission using average times of aircraft maneuvers taken from aircraft Flight Data Recorder (FDR) in the LTO cycle various aircraft types at the airport. The latter, based on actual maneuvering times, lead to significantly reduced estimates of toxic exhaust gas emission volumes. Ecology
aircraft turbine engine
engine exhaust
toxic exhaust gas components
nitrogen oxides
carbon monoxide
hydrocarbons
carbon dioxide
2021226363-7010.2478/TAR-2021-0011Transactions on Aerospace Research
Aleksandrs Bitinš, Juris Maklakovs, Ruta Bogdane, Rafał Chatys, Vladimir ShestakovUsing adverse event pyramids to assess probabilities in airline safety management.Aircraft operationsThis article reviews the methods of safety management using Heinrich’s and Bird’s pyramids. The presence of a causal relationship between pyramid levels, as a result of inconsistencies in the activities of an organization and personnel, lead to incidents, and incidents in turn lead to accidents. The existence of such a relationship makes it possible to predict the risk of “top-level” events by reducing risks at the middle and lower levels. A mathematical description of the development process of an undesired aviation event is presented, which makes it possible to evaluate the probability of the successful (or unsuccessful) completion of a transportation task. Also given is an analysis of the development of an aviation accident, based on the example of the crash of a Lufthansa A-320 aircraft on 14 September 1993 at the airport of Warsaw (Poland) while landing in adverse weather conditions. Airline safety management
risk analysis
2021226371-8310.2478/TAR-2021-0012Transactions on Aerospace Research
Arkadiusz RodakCOMPREHENSIVE AVIATON SYSTEM OF FLYING CREW IMPROVING SAFETY IN THE AIRCRAFT OPERATIONAIRCRAFT OPERATIONSThe article describes 10 known programmes of practical flight training in military aviation – specialization: Multi-Mission Tactical Jet Pilot, which is the highest level of military pilot training in all types of military and civil aviation – comparable only to the level of training and experience of the pilot-instructor of the Military Aviation School. The presented comparison was developed on the basis of literature research from the point of view of, among others, an aircraft operation engineer and a pilot-instructor. TS-11 “Iskra”
flight training
military pilot
flight safety
201912541-1610.2478/TAR-2019-0001Transactions on Aerospace Research
Robert S. RowińskiMATHEMATICAL MODEL SAND COMPUTER SIMULATIONS OF AERIAL SPRAYINGAND DROPLETS DISTRIBUTION IN A TARGET SITEAircraft operationsMathematical models describing aerial spraying and the distribution of liquid droplets on a target were presented. Relationships based on “free models” with Gaussian distribution of droplet concentrations and “bound models” that account for the impact of disturbances in the velocity field behind agricultural aircraft were expanded, and the hybrid model too. The results of experimental studies were presented and compared with theoretical calculations. The “bound model” was found to be the most effective solution for describing the physical phenomena that accompany the aerial spraying process. agricultural aviation
aerial spraying
drift
2019325624-4210.2478/TAR-2019-0015Transactions on Aerospace Research
Tomasz Seredyn, Adam Dziubiński, Piotr JaśkowskiCFD Analysis of the Fluid Particles Distribution by Means of Aviation TechniqueAircraft operationsThe article describes a computational study, using CFD models, of droplet spray dispersal in the wake of a ‘Turbo Kruk’ airplane up to 500 m downstream. The CFD Reynolds-averaged Navier-Stokes (RANS) models use a Lagrangian (droplet phase) and Eulerian (fluid phase) procedure to predict the droplet trajectories trough the turbulent aircraft wake. The methods described in the work have the potential to improve current models for aerial spraying and will help in the development of new spraying procedures. In this study, the CFD models are used to describe the phenomenon of sprays released from atomizers mounted on the plane. A parametric study of the aircraft model examines the effects of crosswind on the aircraft’s vortex structures and the resulting droplet trajectories. The study shows, that such influence is underestimated in the current models. A comparison of the present results to AGDISP predictions is provided. Droplets dispersion modeling
Pesticide spraying
Agricultural aircraft wake
2018125067-9710.2478/TAR-2018-0006Transactions on Aerospace Research
Wojciech G. MiksaAir taxi flight sharing.Aircraft operationsIn traditional air taxi model, flight route and timing are assigned to every order individually, resulting in minimum utilization of seats, maximum number of empty legs and elevated price levels. Sharing flights, when possible, allow decreasing number of empty seats and distributing cost of flight among customers. Challenges to overcome are varying timing needs of customers and volatility of demand.
This article investigates possibilities of synchronizing passenger orders. The proposed passenger pooling model replaces specific flight timing on order with constraints: latest arrival and earliest departure to provide room for coordination of orders, backed by web-based ICT. Theoretical test cases calculations verify the concept and compare it with traditional full on-demand and scheduled operations.
air taxi;
service model;
shared service;
load factor
2020326049-6310.2478/TAR-2020-0016Transactions on Aerospace Research
Bartosz Brzozowski, Karol Kawka, Krzysztof Kaźmierczak, Zdzisław Rochala, Konrad WojtowiczSupporting the Process of Aircraft Maintenance with Mobile DevicesAircraft operationsMaintenance of aircraft is a complex process and therefore, in order to optimize the process, integrated information systems are increasingly used. Rapid development and wide availability of mobile devices equipped with powerful processors and with a wide range of modern communication connections suggests their high usability for enterprise IT systems. In the Department of Avionics and Air Armament of the Military University of Technology (WAT) an ERP-class (Enterprise Resource Planning) system, intended to support aircraft maintenance [4] has been designed and developed. The main concept of the system is to store the aircraft related and maintenance information in a central repository, i.e. in databases hosted on a central database server. This solution ensures concurrent availability of the data to a large group of authorized users. The key components of the system include the database server and client applications, which ensure access to centralized information resources, according to assigned user rights. The project involves development of client applications using three technologies: web, desktop and mobile one. Developed client applications have successfully passed integration tests perfomed using sample maintenance data. Currently works on user authorization security and wireless data security are under way. maintenance system
mobile application
aircraft
201722477-1810.2478/TAR-2017-0011Transactions on Aerospace Research
Robert KonieczkaMi-2 Helicopters Used within the Structures of the Aviation Detachment of the Ministry of InteriorAircraft operationsIn the article, the author presents the wide-scale use of Mi-2 helicopters in the different entities subordinated to the Minister of Interior - from the introduction of the design, until the present. Insights are presented pertaining to the early stages of the helicopter’s service life within the structures of the 103rd NJW MSW Aviation Regiment in the 1960s. The article describes selected aspects related to the introduction of the design, training, operational use and problems encountered. The service life of Mi-2 helicopters operating within the structures of the Ministry of Interior ended upon liquidation of the Ministry’s Aviation Detachment. That is when another chapter in the history of the helicopters was started, this time operated within the structures of the Police and Border Guard forces, where their service life has not been fully used up until this day. The paper describes the reality of every-day use to perform specific tasks, presents the location of aerodromes, touches upon a shift in the philosophy behind the use of the helicopters, and describes their strong and weak points. The PZL-Kania helicopter has been also presented, being a modernized version of the Mi-2, and still used in Poland within the aviation forces of the Ministry of Interior and Administration. Ministry of Interior and Administration
Mi-2 helicopter
public safety
Nadwiślańskie Jednostki Wojskowe
Border Guard
Police
2018225134-5010.2478/TAR-2018-0014Transactions on Aerospace Research
Miłosz RusieckiMi-2 Helicopters Operating at SeaAircraft operationsThe article describes participation of Mi-2 helicopters in both military and civilian operations at sea. Although the multipurpose Mi-2 rotorcraft were not designed to operate in the harsh environment over the sea, they became - in the second half of the 1960s and in the 1970s - a standard type performing a wide array of tasks at sea. Modern turboshaft engines, a favorable weight-to-power ratio and a dual engine configuration were all factors enabling safe flight over the sea, at considerable distances from land. The specialized Mi-2RM variant designed by WSK PZL Świdnik provided the Naval Aviation with an opportunity to establish, in the 1st half of the 1970s, a unique marine air rescue system. The last Mi-2RM used for rescue missions was decommissioned as late as in 2010, although at that stage it was only used for aircrew training purposes. The Navy was also using the Mi-2Ch variant tasked with creating smokescreens to conceal vessels and port facilities. General purpose variants of the helicopter were used to transport people and goods. They also performed well during patrolling missions and while identifying various types of contamination. helicopters
sea operations
Mi-2 versions
military and civilian use of the Mi-2 helicopter
2018225160-7610.2478/TAR-2018-0016Transactions on Aerospace Research
Albert Zajdel, Cezary Szczepański, Mariusz Krawczyk, Jerzy Graffstein, Piotr MasłowskiSelected Aspects of the Low Level Automatic Taxi Control System ConceptAircraft operationsTaxiing of manned and remotely piloted aircraft is still performed by pilots without using a system of automatic control of direction and speed. Several reasons have emerged in recent years that make the automation of taxiing an important design challenge. The reasons are: decreased airport capacity due to the growing number of aircraft, poor ground operation conditions during poor visibility conditions, an increase in workload of pilots and air traffic controllers and the integration of simultaneous ground operations of manned and remotely piloted air vehicles. This paper presents selected aspects of the concept of a Low Level Automatic Taxi Control System. In particular, it emphasizes the means of controlling an aircraft during taxiing, accuracy requirements of the system and proposes control techniques. The resulting controller of the system is adaptable for different aircrafts. The actuators and their mechanical connections to available controls are the aircraft specific part and are designed for the particular type – in this case – a general aviation light airplane. taxi
taxiing
automatic taxi
taxi control system
2017224769-7910.2478/TAR-2017-0016Transactions on Aerospace Research
Rafał Chatys, Anna Stefańska, Krzysztof Piernik, Konrad StefańskiEstimation of Strength Parameters of Aviation Products Made of Polymer Composites Based on Markov Chain TheoryAircraft structuresThe study investigates the fatigue strength of a component made of a glass composite material with polyester matrix, manufactured using a contact method (I) and by vacuum bagging (II). Modeling was carried out only for composite material II, due to significant spread of the strength of the composite material manufactured by contact lamination I, which means that such a material does not guarantee repeatability of the test results. Estimation of the composite material fatigue strength and residual strength was performed using a mathematical model based on the Markov chain theory. The model assumed that the material failure occurs at certain critical microvolume of the components operating within the plastic range. Observed relationships between the probability values and the distribution parameters for the static strength of the composite components, as well as the load values allow for deriving a fatigue curve equation. Obtained results are presented in the tables. composite material
composite testing
fatigue strength
residual strength
Markov’s theory
2017224719-3010.2478/TAR-2017-0012Transactions on Aerospace Research
Marcelina Bobrowska, Michał Barcikowski, Radosław RybczyńskiResearch of Dependence of the Damage Area on Tow Width on Filament-Wound Composite TubesAircraft structuresThis paper explores the effect of tow width on the damage area produced by high velocity impacts on glass fiber/epoxy composite structures made by filament winding. The subject of the research were a four-layered composite tubes that have been designed using matrix method. The method was used to select mosaic patterns with different rest of the winding stroke and number of interlaces, which are places of stress concentration and which affect the strength of the composite. The narrowest (5 mm) and the widest (17 mm) tow width available was chosen. Composite filament-wound structures were subjected to a high velocity impact by a 2.0 g spherical hardened steel impactor propelled to a velocity of 140 ÷ 170 m/s using a gas gun. It was observed that dependence of the damage area on tow width on filament-wound composite tubes is possible. Filament-wound composite structures
impact damage
ballistic impact
filament winding
201712467-1410.2478/TAR-2017-0001Transactions on Aerospace Research
Rafał Chatys, Anna Stefańska, Krzysztof Piernik, Konrad StefańskiEstimation of Strength Parameters of Aviation Products Made of Polymer Composites Based on Markov Chain TheoryAircraft structuresThe study investigates the fatigue strength of a component made of a glass composite material with polyester matrix, manufactured using a contact method (I) and by vacuum bagging (II). Modeling was carried out only for composite material II, due to significant spread of the strength of the composite material manufactured by contact lamination I, which means that such a material does not guarantee repeatability of the test results. Estimation of the composite material fatigue strength and residual strength was performed using a mathematical model based on the Markov chain theory. The model assumed that the material failure occurs at certain critical microvolume of the components operating within the plastic range. Observed relationships between the probability values and the distribution parameters for the static strength of the composite components, as well as the load values allow for deriving a fatigue curve equation. Obtained results are presented in the tables. composite material
composite testing
fatigue strength
residual strength
Markov’s theory
2017224719-3010.2478/TAR-2017-0012Transactions on Aerospace Research
Marcelina Bobrowska, Michał Barcikowski, Radosław RybczyńskiResearch of Dependence of the Damage Area on Tow Width on Filament-Wound Composite TubesAircraft structuresThis paper explores the effect of tow width on the damage area produced by high velocity impacts on glass fiber/epoxy composite structures made by filament winding. The subject of the research were a four-layered composite tubes that have been designed using matrix method. The method was used to select mosaic patterns with different rest of the winding stroke and number of interlaces, which are places of stress concentration and which affect the strength of the composite. The narrowest (5 mm) and the widest (17 mm) tow width available was chosen. Composite filament-wound structures were subjected to a high velocity impact by a 2.0 g spherical hardened steel impactor propelled to a velocity of 140 ÷ 170 m/s using a gas gun. It was observed that dependence of the damage area on tow width on filament-wound composite tubes is possible. Filament-wound composite structures
impact damage
ballistic impact
filament winding
201712467-1410.2478/TAR-2017-0001Transactions on Aerospace Research
Wiesław KrzymieńMechanical properties of the package of ferromagnetic sheetsAircraft structuresThe paper presents the measurement method and results as well as the results of comparative calculations aimed at determination of material data for the package of ferromagnetic sheets insulated with epoxy lacquer. During the test, the package of sheets was treated as a 3D orthotropic material. The values of Young’s and Kirchhoff’s moduli for a pre-compressed package of sheets, in accordance with the used manufacturing technology of the medium and high power electric motors’ rotors, were detennined. The carried out FEM comparative calculations confirmed that the determined mechanical parameters of the package of sheets as a 3D orthotropic material, i.e. Young’s and Kirchhoff’s moduli, for the compressive stress range of 1.0÷2.5 MPa, are included in the linear range. It was assumed that the determined mechanical properties of the package of sheets are necessary at the design stage for FEM simulation calculations of the electric motors’ vibration and strength properties. As a result of the tests, it was found that they should be repeated in order to determine the properties of other sheets or those coated with different insulating lacquer. asynchronous motor
package of sheets
FEM
vibration
2017124654-6210.2478/TAR-2017-0006Transactions on Aerospace Research
Marcin Spiralski, Karol Bęben, Wojciech Konior, Dawid CieślińskiHigh Altitude Ballooning as an Atmospheric Sounding System in the Pre-Flight Procedures of ILR-33 AmberAtmospheric soundingThe paper presents research on the near real-time atmospheric sounding system. The main objective of the research was the development and testing of the weather sounding system based on a weather balloon. The system contains a redundant system of radiosondes, a lifting platform containing weather balloon and a holding system as well as ground station. Several tests of the system were performed in August and September 2019. Altitude, reliability, resistance to weather conditions and data convergence were tested. During tests, new procedures for such missions were developed. The final test was performed for the ILR-33 Amber Rocket as a part of pre-launch procedures. The test was successful and allowed to use acquired atmospheric data for further processing. Several post-tests conclusions were drawn.
The altitude of sounding by a weather balloon depends mostly on weather conditions, the amount of gas pumped and the weight of a payload. The launching place and experience of the crew play an important role in the final success of the mission, as well.
weather balloon,
unmanned free balloon, a
tmosphere sounding,
radiosonde,
remote sensing,
Earth observation
2020125866-7710.2478/TAR-2020-0005Transactions on Aerospace Research
Wiesław Masłowski, Tadeusz Opara, Michał BurekPosturographic Tests of Candidates for Military PilotsAviation MedicineOne of the many elements of the process of qualifying the candidates for military aircraft pilots is the assessment of the correct functioning of their body balance system, responsible, inter alia, for spatial orientation during a flight. That system continuously controls the spatial position of the center of body mass. To measure that value directly is a complex metrological task. That is why an equivalent measure is used in tests of standing posture stability, i.e. the position of a projection of the center of mass on a supporting plane. posturography
body mass center position
balance system
force platform
2017224745-5610.2478/TAR-2017-0014Transactions on Aerospace Research
Ohlenforst Barbara, Ligthart Seth, Aalmoes Roalt, Dirk Schreckenberg and Maykel van MiltenburgAssociation between short-term annoyance and several physiological parameters during different amounts of nocturnal aircraft noise exposure.Aviation noiseAnnoyance is the most prevalent community response to environmental noise. Observational and experimental lab studies have shown that exposure to environmental noise leads to annoyance, sleep disturbance, daytime sleepiness, increased heart rate and increased blood pressure. However, previous literature is preliminary based on controlled settings or experimental design, raising the question of
the generalizability and applicability in daily life scenarios. This study aimed to investigate two main research questions. First, what is the relationship between short-term annoyance and different amounts of nocturnal aircraft noise exposure in daily life? Second, what is the relationship between physiological parameters, including heart rate, number of awakenings, sleep efficiency, sleep duration and different amounts of nocturnal aircraft noise exposure in daily life? This study also aimed to explore the suitability of non-invasive commercially available activity trackers to measure physiological metrics in a scientific way. During this field study, participants were wearing Fitbit Charge 3 activity trackers recording heart rate and different sleep-derived metrics (e.g. deep sleep duration, sleep efficiency and awakenings).
The used activity trackers were readily available, non-intrusive, relatively cheap and easy to use by
the participants. Simultaneously, a logbook was used by the participants to track the subjective perception and situational context of air traffic noise exposure. The noise levels corresponding to the exposure of air traffic of each participant were calculated based on the location of the participant and the corresponding radar track using an aircraft noise monitoring system.
We hypothesize that a higher amount of exposure to aircraft noise in real life will be associated with increased annoyance, increased rest heartrate, higher number of awakenings, decreased sleep efficiency and decreased deep sleep duration.
Preliminary results on the interactions between aircraft noise exposure, perceived annoyance and physiological metrics suggest increased nocturnal aircraft noise exposure seems to negatively affect sleep efficiency and deep sleep duration.
Aviation,
aircraft noise,
short-term annoyance,
heart rate,
deep sleep,
sleep efficiency,
awakenings,
actigraphy.
202042611-1210.2478/TAR-2020-0018Transactions on Aerospace Research
Pawel Zakrzewski, Janusz Narkiewicz, Darren BrenchleySafety Critical Software Development Methodologies in AvionicsAvionicsThis article summarizes avionics safety-critical software development methodologies and implications of the DO-178C standard from an Agile application perspective. We explain the safety-critical software categorization. It also outlines the main differences and advantages of different approaches to the development process, from Waterfall through the V-model to Iterative and Incremental. Agile principles are explained
as well as a Scrum – which is a popular framework in the non-safety-critical software industry.
The application of Agile, for safety-critical software considerations, is based on the practical knowledge of the authors, and looks at the potential solution from a DO-178C standard, size of the project, scalability, and organizational culture points of view. Definition of the Agile type of framework, consistent with the certification process and existing standards, has been highlighted as a potential game-changer for the avionics industry.
Avionics,
Safety
Critical Software,
Agile,
Systems Engineering
2020225959-7110.2478/TAR-2020-0011Transactions on Aerospace Research
Jacek Pieniążek, Paulina RybaEddy-Current Sensor for a TachometerAvionicsThe speed of a rotor or rotors of a turbine engine is important information on its operation. Due to the specific conditions, in which the measurement is taken in a turbine engine, which in particular applies to small engines that are becoming increasingly popular in manned and unmanned aviation, the most universal detector is the detector using the phenomenon of eddy currents. This article presents the developed detector system solution. The correct operation of a detector is conditional upon the possibility to detect the presence of a blade in the detection field in a reliable manner, while maintaining the resistance to interference. The developed system is resistant to changes in parameters due to the use of a differential system consisting of two detector coils connected in a bridge circuit, a rectifier circuit with filters acting as a demodulator and a comparator. The system works with a microprocessor performing data processing functions. The executed functional model was tested in a laboratory, which enabled to determine its characteristics in several configurations and to confirm its correct operation. rotational speed
eddy currents
measurement system
2017224757-6810.2478/TAR-2017-0015Transactions on Aerospace Research
Bogusław Dołęga, Grzegorz Kopecki, Andrzej TomczykAnalytical Redundancy in Control Systems for Unmanned Aircraft and Optionally Piloted VehiclesAvionicsThe article presents key properties of a module intended to estimate non-measurable state variables of an aircraft (a fixed-wing aircraft). Sample calculations are applicable to the MP-02A Czajka light Optionally Piloted Vehicle (OPV). The quality of flight parameter values’ estimation is illustrated by comparing flight parameters of the MP-02A Czajka aircraft recorded during actual flight with estimated values of respective parameters calculated during simulation of selected sensor faults. This experiment allows to evaluate the usefulness of the analytical redundancy mechanism that determines attitude parameters (roll, pitch and heading angles) and navigational variables (airspeed, altitude and geographic coordinates). on-board measurement systems
analytical redundancy
UAV
optionally piloted vehicles
2017224731-4410.2478/TAR-2017-0013Transactions on Aerospace Research
Marcin ŻugajReconfiguration of Unmanned Aircraft Control SystemAvionicsReliability of unmanned aircraft is a decisive factor for conducting air tasks in controlled airspace. One of the means used to improve unmanned aircraft reliability is reconfiguration of the control system, which will allow to maintain control over the aircraft despite occurring failures. The control system is reconfigured by using operational control surfaces, to compensate for failure consequences and to control the damaged aircraft. Development of effective reconfiguration algorithms involves utilization of a non-linear model of unmanned aircraft dynamics, in which deflection of each control surface can be controlled independently. control
reconfiguration
unmanned aircraft
2017224780-9610.2478/TAR-2017-0017Transactions on Aerospace Research
Marcin Żugaj, Przemysław Bibik, Marcin FigatAn Unmanned Aircraft Model for Control System Reconfiguration Analysis and SynthesisAvionicsReliability of unmanned aircraft is a decisive factor for conducting air tasks in a controlled airspace. One of the means of improving unmanned aircraft reliability is reconfiguration of the control system, which will allow to maintain control over the aircraft despite an occurring failure. The control system is reconfigured by using still operational control surfaces to compensate for failure consequences and to control the damaged aircraft. Development of effective reconfiguration algorithms involves utilization of a non-linear model of unmanned aircraft dynamics, in which each control surface deflection can be controlled independently. flight dynamics
control
reconfiguration
2017224797-11610.2478/TAR-2017-0018Transactions on Aerospace Research
Bogusław Dołęga, Grzegorz Kopecki, Andrzej TomczykAnalytical Redundancy in Control Systems for Unmanned Aircraft and Optionally Piloted VehiclesAvionicsThe article presents key properties of a module intended to estimate non-measurable state variables of an aircraft (a fixed-wing aircraft). Sample calculations are applicable to the MP-02A Czajka light Optionally Piloted Vehicle (OPV). The quality of flight parameter values’ estimation is illustrated by comparing flight parameters of the MP-02A Czajka aircraft recorded during actual flight with estimated values of respective parameters calculated during simulation of selected sensor faults. This experiment allows to evaluate the usefulness of the analytical redundancy mechanism that determines attitude parameters (roll, pitch and heading angles) and navigational variables (airspeed, altitude and geographic coordinates). on-board measurement systems
analytical redundancy
UAV
optionally piloted vehicles
2017224731-4410.2478/TAR-2017-0013Transactions on Aerospace Research
Marcin ŻugajReconfiguration of Unmanned Aircraft Control SystemAvionicsReliability of unmanned aircraft is a decisive factor for conducting air tasks in controlled airspace. One of the means used to improve unmanned aircraft reliability is reconfiguration of the control system, which will allow to maintain control over the aircraft despite occurring failures. The control system is reconfigured by using operational control surfaces, to compensate for failure consequences and to control the damaged aircraft. Development of effective reconfiguration algorithms involves utilization of a non-linear model of unmanned aircraft dynamics, in which deflection of each control surface can be controlled independently. control
reconfiguration
unmanned aircraft
2017224780-9610.2478/TAR-2017-0017Transactions on Aerospace Research
Marcin Żugaj, Przemysław Bibik, Marcin FigatAn Unmanned Aircraft Model for Control System Reconfiguration Analysis and SynthesisAvionicsReliability of unmanned aircraft is a decisive factor for conducting air tasks in a controlled airspace. One of the means of improving unmanned aircraft reliability is reconfiguration of the control system, which will allow to maintain control over the aircraft despite an occurring failure. The control system is reconfigured by using still operational control surfaces to compensate for failure consequences and to control the damaged aircraft. Development of effective reconfiguration algorithms involves utilization of a non-linear model of unmanned aircraft dynamics, in which each control surface deflection can be controlled independently. flight dynamics
control
reconfiguration
2017224797-11610.2478/TAR-2017-0018Transactions on Aerospace Research
Mycola Chernyak, Vadym KolesnykThe accuracy of the navigational accelerometer with a nonlinear metrological model in operating conditionsAvionicsA mathematical model of the error of the navigational accelerometer caused by the nonlinearity
of its metrological model, taking into account the influence of vibration, was developed. The method of experimental estimation of the vibration error based on the developed model was proposed. The main idea of the method is to evaluate parameters of the developed model during static tests in the terrestrial gravitational field and to calculate error according to the specific vibration characteristics – the amplitude in the case of harmonic vibration profile or the frequency band and the power spectral density in the case of random vibration. The effectiveness of the proposed method has been tested using three types of navigation accelerometers in comparison with the results of classical dynamic testing in various vibration conditions (harmonic, white noise, etc.).
navigational accelerometer,
vibration error,
metrological model,
conversion function,
identification of coefficients,
static test.
202032601-1010.2478/TAR-2020-0012Transactions on Aerospace Research
Paweł SkalskiBionics in aviationBioinspirationIn the paper bionics as a field of knowledge and inspiration in the aviation technologies is presented. Bionics is a branch of science on the borderline of art and biology that studies the way living organisms work, as well as their structure, in order to use the results to build technical devices. In the introduction part definition of bionics is described. In the next part of this document the aviation technologies inspired by nature is depicted. Then, technologies inspired by the butterfly wing are presented. The paper ends with conclusions. bionics
aviation
butterfly wing
20183252103-11310.2478/TAR-2018-0025Transactions on Aerospace Research
Arnold JędralREVIEW OF TESTING METHODS DEDICATED FOR SANDWICH STRUCTURES WITH HONEYCOMB CORECOMPOSITE MATERIALSThis paper is a review of testing methods dedicated for sandwich type composite structures with honeycomb core. First, information about the composition of sandwich materials structures, their properties, types of core materials and applications in the industry is presented. Mechanical properties were compared in the case of different types of the core material. Later, tests methods needed to describe properties of those materials and normalization organizations which create them were mentioned. The testing methods were divided into two groups: mechanical and physicochemical tests. Mechanical properties are: compressive strength (two types of test), edge compressive strength, shear strength (in two directions) and tension strength (two types of test). Physicochemical properties are: material density, water migration, water absorption and thermal conductivity. Testing methods were described according to American Society for Testing and Materials (ASTM) standards. This article is based on professional literature and the author’s experience. mechanical properties
sandwich panel materials
honeycomb
Kevlar
Nomex
201922557-2010.2478/TAR-2019-0006Transactions on Aerospace Research
Mateusz Michalski, Wojciech KrauzeINFLUENCE OF HONEYCOMB CORE STABILIZATION ON COMPOSITE SANDWICH STRUCTURE GEOMETRYCOMPOSITE MATERIALSAuthors showed the influence of stabilization of the honeycomb core on shape of the composite sandwich test panel. Adhesive film laid on core ramps and cured with suitable cure cycle served as core stabilizer. Test panel geometry included different ramp angles (20° and 30°). To verify stabilization process a technology trial was performed. Three test panels were manufactured (3-stage, 1-stage and 1-stage with stabilized core). All test panels were manufactured in OoA process (Out of Autoclave). Panel surfaces were scanned with 3D scanner and compared with the reference CAD model. Both outer skin and inner skin were manufactured in Automated Fiber Placement Laboratory of Warsaw Institute of Aviation. composite
carbon fiber
sandwich structure
AFP
thermoset material
201932561-1310.2478/TAR-2019-0013Transactions on Aerospace Research
Maciej KarnyDETERMINATION OF IN-PLANE SHEAR PROPERTIESOF LAMINATE WITH V-NOTCH RAIL SHEAR TESTAND DIGITAL IMAGE CORRELATIONCOMPOSITE MATERIALSThis article presents the results of the application of Digital Image Correlation (DIC) to measurements of in-plane shear modulus and strength of three different carbon fiber reinforced laminates. Three different approaches to shear strain calculations via DIC are evaluated and compared with standard strain gage measurements. Calculation of shear strain based on averaging DIC strain values of strain gages area in most cases yielded results closest to strain gages, while measurements based on single point strain measuring differed the most from strain gages. These results are attributed to shear strain distribution in the center area of the specimen. Thermoplastic matrix fabric reinforced composite had the lowest shear strength at 5% of shear strain, but the highest ultimate shear strength and strain at failure. Of thermosetting materials, laminate reinforced with unidirectional carbon fiber had shear modulus about 10% lower, than fabric reinforced laminate, but higher ultimate strength and strain at failure. This behavior is attributed to the presence of weaves in fabric reinforcing the laminate, causing shear stiffening of the material, but lowering its ability to deform under shear loading. Digital Image Correlation
in-plane shear
thermoplastic laminates
v-notch rail shear
2019325657-6510.2478/TAR-2019-0017Transactions on Aerospace Research
Rafał Szymański, Mateusz ZiębaManufacturing and Testing of Carbon Composite Samples Intended for AviationCOMPOSITE MATERIALSThe paper presents the manufacturing technology and quality control of samples made of composite materials intended, inter alia, for aircraft elements. The samples are made from carbon fiber reinforced prepreg in a polymer matrix which is commonly used in the aerospace industry. The authors described the dimensional requirements for samples made of composite materials for strength testing, and the main stages of production which have a direct impact on the quality of composite samples. Also presented is the technological process of producing flat carbon composite panels for composite samples, cutting the produced panels with a CNC plotter, cutting the samples on a conventional milling machine, and surface treatment of the samples on a surface grinder. The machining parameters that were experientially found to be optimal for the milling and grinding of carbon samples are specified as well. Finally, the method of quality control of the ready composite samples is described and solutions are presented to improve the production of high-quality samples. carbon prepregs
composite technology
vacuum consolidation
strength testing
20173248107-11610.2478/TAR-2017-0024Transactions on Aerospace Research
Michał SokołowskiProcess of Preparing and Laying Carbon PrepregsCOMPOSITE MATERIALSThis article contains information on the technological process involved in the production of a composite structure with carbon-epoxy prepregs including critical parameters of the process. The information in the publication shows respectively:
1. Using composite components for constructing the airframe,
2. ways of storing and preserving carbon prepregs on a matrix of thermosetting resins,
3. specific types of varying weave fabrics used in the prepregs,
4. way of preparing material for the process,
5. cutting tools,
6. preparing swage,
7. list of the most popular materials, their characteristics, pros and cons of their applications,
8. issues related to types of release agent,
9. parameters of selecting release agents in the process of manufacturing structures with carbon prepregs,
10. process of laying plies in a layered structure,
11. defects which result from improper material laying in swage,
12. preparing the structure for heating and technical parameters of the process.
carbon prepreg
composite material
release agents
swage
2017124627-3410.2478/TAR-2017-0003Transactions on Aerospace Research
Maciej KarnyThe influence of the fastener hole preparation method on the fastener pull-through process in a carbon compositeCOMPOSITE MATERIALSThis article studies the pull-through resistance of a titanium carbon fibre-epoxy resin laminate fastener. Coupons with fastener holes made with different methods were compared – drilled, milled on a CNC plotter and special fibre application during laminate production. The tests were conducted according to the ASTM D7332 test standard. The studies showed that the fastener hole preparation method impacts the laminate’s resistance to fastener pull-through. Coupons with holes made with standard (drilling and milling) methods showed fastener pull-through resistance higher, on average, by 6.5% than in coupons with holes placed during plate production. Fastener work to rupture was also higher for coupons with milled and drilled holes. Microscopic observations in UV-light, using a fluorescent penetrant, showed differences in failure mechanisms between individual coupons, especially the lack of fibres in the 0° direction, in immediate vicinity to a hole prepared during laminate application. composites
fastener pull-through
ASTM D7332 standard
drilling
2017124645-5310.2478/TAR-2017-0005Transactions on Aerospace Research
Rafał SzymańskiQuality control process of manufactured composite structuresCOMPOSITE MATERIALSThe paper includes a description of the composite material used in the aviation industry. It presents the technological development of composites in terms of their use in the most important elements of the aircraft structures, such as a spar and aircraft wing sheathing, which are subjected to high loads during operation. The type of the material implemented for production was listed and the most commonly occurred incompatibilities during the carbon pre-impregnate manufacture and transport were described.
The manufacture diagram of composite elements with a polymer matrix was presented and the quality control system carried out at each mentioned stage (material storage, defrosting, cutting of dies, structure forming, polymerisation) was discussed.
The methods of non-destructive tests of carbon laminates in a polymer matrix were also listed, describing the most effective of them, i.e. a method of ultrasonic tests.
The conclusions were drawn and the development possibilities of ultrasonic tests both in terms of quality improvement and reduction of time for detecting incompatibilities in composite structures were described.
pre-impregnate
composite technology
non-destructive tests with the use of an ultrasonic method
2017124695-10310.2478/TAR-2017-0009Transactions on Aerospace Research
Anna BonaTheoretical and experimental review of applied mechanical tests for carbon composites with thermoplastic polymer matrixCOMPOSITE MATERIALSThis article has a theoretical and experimental character. It presents the characteristics of two main thermoplastics used in the aerospace industry – poly ether ether ketone (PEEK) and poly phenylene sulphide (PPS). The selected materials are compounds for the production of thermoplastic polymer matrix composites. The paper presents a literature review of the application of thermoplastic polymer matrix composite materials in aviation. Additionally, the paper focuses on the characteristics of carbon fibre-reinforced polymer (CFRP) which plays an important role in the production of aerospace components. Testing methods have been chosen on the basis of the type of composite matrix. The article contains the most important mechanical properties and general characteristics of thermoplastics used as a matrix for CFRP type composites used in the aerospace industry. Individual test procedures which allow for the evaluation of mechanical properties of composite materials on a thermoplastic polymer matrix, have been described. Mechanical tests such as static tensile test and bending of short beams were carried out in order to examine CFRP compositescarbon fibre composites,
PEEK,
PPS,
CFRP,
thermoplastics,
investigations of PEEK and PPS composites.
2019425755-7910.2478/TAR-2019-0023Transactions on Aerospace Research
Piotr Bajurko, Przemysław DobrzańskiExperimental Verification of Numerical Calculations with the Use of Digital Image CorrelationCOMPOSITE MATERIALSThe article presents the results of research work performed under the TEBUK project, aiming primarily to develop a reference methodology for assessing the impact of damage on the strength of structures made of carbon epoxy prepregs. The tests described in the paper were concerned with a fragment of the structure (FS) of the TEBUK project demonstrator, made of carbon epoxy composite, with an artificial circular delamination measuring 40 mm in diameter. Numerical and experimental test of FS have been performed under quasi-static compression load. The buckling of the skin observed in the delamination area, as well as the propagation of the latter were investigated. The numerical calculations have been performed with the use of the commercially available MSC Marc/Mentat calculation suite based on the Finite Elements Methods. Results of the numerical calculations have been compared with experimental measurements made with the use of the Digital Image Correlation (DIC) method. The tests performed aimed to provide a preliminary verification of the numerical model. The results obtained have shown a very good correlation between the numerical and experimental results concerned with critical load levels at which stability of the layers separated by delamination is lost (buckling). The lack of convergence of the numerical model’s results after exceeding the critical load values has rendered it impossible to unequivocally compare the results concerned with propagation of the delamination area. digital image correlation
FEM
delamination
buckling
carbon-epoxy laminate
201822511-1510.2478/TAR-2018-0011Transactions on Aerospace Research
Robert JaśkiewiczImplementation of Automatic Sample and Composite Element Cutting TechnologiesCOMPOSITE MATERIALSThe article presents the methodology of introducing automatic carbon fiber panel cutting technologies at the Composite Testing Laboratory of the Institute of Aviation. It describes the process of implementing the new cutting technology which boosts the efficiency of preparing composite samples for strength testing, with the requirements applicable to edge smoothness and dimension tolerances taken into consideration. It also reviews the literature concerned with three most popular composite material cutting methods: laser cutting, abrasive water jet cutting and machining, presenting the strong and the weak points of each one of them. After selecting the machining technology relying on a disc, cutting tests have been performed. Cutting discs coated with diamond particles, and carbon fiber panels were used during the tests. The tests were performed with the use of the INFOTEC CNC machine, with an adapter enabling the installation of cutting discs with the maximum diameter of 150 mm. composite cutting
automatic cutting
CNC cutting
carbon fiber machining
2018225124-3310.2478/TAR-2018-0013Transactions on Aerospace Research
František LöffelmannStress Distribution Investigation at the Tapered Sandwich EndingsCOMPOSITE MATERIALSOne of the typical sandwich ending is tapered transition to a solid laminate, which causes significant stress distribution changes. The reviewed articles show that tapered area causes increase in the shear stress in the core, increase of the axial forces in the facesheets and local bending at the fork point, at points of the tapering angle change, and at ply drop positions. Most of the studies gave attention to the endings without reinforcing. During Erasmus+ internship at KTH 2D model of the tapered ending with reinforcing plies, various geometry and resin filler in the core tip was investigated to see the influence on the stress distribution. It was found that tension load case is not as critical as bending load case. Increasing of the solid laminate thickness, adding plies and inserting a short resin or adhesive filler into the core tip area lead to significant stress reduction, whereas in the transition point, from tapering to constant thickness sandwich, increasing radius is more efficient than reinforcing plies in regard to reduce stress concentration. Sandwich endings
Tapering
Ramp
Closeout
FEM
Filler
Ply drop
2017424964-8110.2478/TAR-2017-0029Transactions on Aerospace Research
Robert JaśkiewiczComparison of composite laminates machining methods and its influence on process temperature and edge qualityCOMPOSITE MATERIALSThe article presents the description of technological trials and the results of three methods of machining carbon fiber reinforced composites panels. It also reviews the literature concerned heat affected zone in composites and its influence on material properties. As a part of the research, the cutting method using diamond coated saw was tested, as well as the milling method with two different types of carbide milling cutters. The processing of the panels was done using 4-axis CNC machine with special adapter for cutting discs in Composite Testing Laboratory (Center for Composite Technologies, Warsaw Institute of Aviation). The methods were compared in terms of machined edge quality and panel temperature during the processes. For this purpose, thermocouples were mounted into panels. Records from thermocouples were included. Edge quality and surface roughness have been checked by microscopic observation. Additionally, samples machined by each evaluated processing method were tested using differential scanning calorimetry (DSC). The method was used to determine the glass transition temperature of
the tested material. The article conclusions contain a comparison of three processing methods in terms of cutting quality, process temperature, processing method productivity as well as DSC tests results.
CFRP machining,
composite machining temperature,
DSC tests,
temperature tests.
2019425746-5410.2478/TAR-2019-0022Transactions on Aerospace Research
Przemysław DobrzańskiBonding of High Temperature Thermoplastic Carbon Composites with Resistance Welding TechniqueCOMPOSITE MATERIALSThe article presents ‘state-of-the art’ on joining fibre reinforced thermoplastic composites with the use of resistance welding technique. Their welding process and potential difficulties connected with the process and quality control of a manufactured element are presented. The structure of a typical thermoplastic composite welding stand was also presented. The main welding technology elements were characterized: structure of the resistance element, implementation of the thermal process and pressure application required for joining materials. The paper also presents the required calibration ranges for a technological process with the use of strength test types SLS, DCB, SBS and nondestructive testing of joint with the ultrasonic method. thermoplastic composites
resistance welding
joining thermoplastic composites
201832521-1310.2478/TAR-2018-0018Transactions on Aerospace Research
Jakub Wilk, Radosław GuzikowskiValidation of numerical models used for designing the composite blade for ILX-27 rotorcraftCOMPOSITE MATERIALSThe paper presents the validation procedure of the model used in the analysis of the composite blade for the rotor of the ILX-27 rotorcraft, designed and manufactured in the Institute of Aviation, by means of numerical analyses and tests of composite elements. Numerical analysis using finite element method and experimental studies of three research objects made of basic materials comprising the blade structure – carbon-epoxy laminate, glass-epoxy composite made of roving and foam filler – were carried out.
The elements were in the form of four-point bent beams, and for comparison of the results the deflection arrow values in the middle of the beam and axial deformations on the upper and lower surfaces were selected. The procedure allowed to adjust the discrete model to real objects and to verify and correct
the material data used in the strength analysis of the designed blade.
composites,
FEM modelling,
mechanical tests.
2019425723-3110.2478/TAR-2019-0020Transactions on Aerospace Research
Rafał Chatys, Anna Stefańska, Krzysztof Piernik, Konrad StefańskiEstimation of Strength Parameters of Aviation Products Made of Polymer Composites Based on Markov Chain TheoryCOMPOSITE MATERIALSThe study investigates the fatigue strength of a component made of a glass composite material with polyester matrix, manufactured using a contact method (I) and by vacuum bagging (II). Modeling was carried out only for composite material II, due to significant spread of the strength of the composite material manufactured by contact lamination I, which means that such a material does not guarantee repeatability of the test results. Estimation of the composite material fatigue strength and residual strength was performed using a mathematical model based on the Markov chain theory. The model assumed that the material failure occurs at certain critical microvolume of the components operating within the plastic range. Observed relationships between the probability values and the distribution parameters for the static strength of the composite components, as well as the load values allow for deriving a fatigue curve equation. Obtained results are presented in the tables. composite material
composite testing
fatigue strength
residual strength
Markov’s theory
2017224719-3010.2478/TAR-2017-0012Transactions on Aerospace Research
Marcelina Bobrowska, Michał Barcikowski, Radosław RybczyńskiResearch of Dependence of the Damage Area on Tow Width on Filament-Wound Composite TubesCOMPOSITE MATERIALSThis paper explores the effect of tow width on the damage area produced by high velocity impacts on glass fiber/epoxy composite structures made by filament winding. The subject of the research were a four-layered composite tubes that have been designed using matrix method. The method was used to select mosaic patterns with different rest of the winding stroke and number of interlaces, which are places of stress concentration and which affect the strength of the composite. The narrowest (5 mm) and the widest (17 mm) tow width available was chosen. Composite filament-wound structures were subjected to a high velocity impact by a 2.0 g spherical hardened steel impactor propelled to a velocity of 140 ÷ 170 m/s using a gas gun. It was observed that dependence of the damage area on tow width on filament-wound composite tubes is possible. Filament-wound composite structures
impact damage
ballistic impact
filament winding
201712467-1410.2478/TAR-2017-0001Transactions on Aerospace Research
Rafał SzymańskiNon-Destructive Testing of Thermoplastic Carbon Composite StructuresCOMPOSITE MATERIALSThe article is in line with the contemporary interests of companies from the aviation industry.
It describes thermoplastic material and inspection techniques used in leading aviation companies.
The subject matter of non-destructive testing currently used in aircraft inspections of composite structures is approximated and each of the methods used is briefly described. The characteristics of carbon pre-impregnates in thermoplastic matrix are also presented, as well as types of thermoplastic materials and examples of their application in surface ship construction. The advantages, disadvantages and limitations for these materials are listed. The focus was put on the explanation of the ultrasonic method, which is the most commonly used method during the inspection of composite structures at the production and exploitation stage. Describing the ultrasonic method, the focus was put on echo pulse technique and
the use of modern Phased Array heads. Incompatibilities most frequently occurring and detected in composite materials with thermosetting and thermoplastic matrix were listed and described.
A thermoplastic flat composite panel made of carbon pre-impregnate in a high-temperature matrix (over 300°C), which was the subject of the study, was described. The results of non-destructive testing (ultrasonic method) of thermoplastic panel were presented and conclusions were drawn.
thermoplastic,
pre-impregnate,
non-destructive testing,
ultrasonic method,
Phased Array.
2020125834-5210.2478/TAR-2020-0003Transactions on Aerospace Research
Piotr BajurkoMODELLING OF THE AEROSPACE STRUCTURE DEMONSTRATOR SUBCOMPONENTComposite structuresCarbon-epoxy composite materials, due to their high strength in relation to mass, are increasingly used in the construction of aircraft structures, however, they are susceptible to a number of damages. One of the most common is delamination, which is a serious problem in the context of safe operation of such structures. As part of the TEBUK project, the Institute of Aviation has developed a methodology for forecasting the propagation of delamination. In order to validate the proposed method, an aerial structure demonstrator, modelled on the horizontal stabilizer of the I-23 Manager aircraft, was carried out. However, in order to carry out the validation, it was necessary to "simplify" the demonstrator model. The paper presents a numerical analysis conducted in order to separate from the TEBUK demonstrator model a fragment of the structure, which was used to study the delamination area, as an equivalent of the whole demonstrator. Subcomponent selection was carried out in several stages, narrowing down the analysed area covering delamination in subsequent steps and verifying the compliance of specific parameters with the same parameters obtained in a full demonstrator model. The parameters compared were: energy release rate values on the delamination front line and strain values in the delamination area. The numerical analyses presented in the paper were performed with the use of the MSC.Marc/Mentat calculation package. As a result of the analyses, a fragment of the structure was selected, which allows to significantly reduce the time and labour consumption of the production of the studied object, as well as to facilitate experimental research. FEM
delamination
buckling
carbon-epoxy composite
2019125437-5210.2478/TAR-2019-0004Transactions on Aerospace Research
Arnold JędralREVIEW OF TESTING METHODS DEDICATED FOR SANDWICH STRUCTURES WITH HONEYCOMB CORECOMPOSITE STRUCTURESThis paper is a review of testing methods dedicated for sandwich type composite structures with honeycomb core. First, information about the composition of sandwich materials structures, their properties, types of core materials and applications in the industry is presented. Mechanical properties were compared in the case of different types of the core material. Later, tests methods needed to describe properties of those materials and normalization organizations which create them were mentioned. The testing methods were divided into two groups: mechanical and physicochemical tests. Mechanical properties are: compressive strength (two types of test), edge compressive strength, shear strength (in two directions) and tension strength (two types of test). Physicochemical properties are: material density, water migration, water absorption and thermal conductivity. Testing methods were described according to American Society for Testing and Materials (ASTM) standards. This article is based on professional literature and the author’s experience. mechanical properties
sandwich panel materials
honeycomb
Kevlar
Nomex
201922557-2010.2478/TAR-2019-0006Transactions on Aerospace Research
Mateusz Michalski, Wojciech KrauzeINFLUENCE OF HONEYCOMB CORE STABILIZATION ON COMPOSITE SANDWICH STRUCTURE GEOMETRYCOMPOSITE STRUCTURESAuthors showed the influence of stabilization of the honeycomb core on shape of the composite sandwich test panel. Adhesive film laid on core ramps and cured with suitable cure cycle served as core stabilizer. Test panel geometry included different ramp angles (20° and 30°). To verify stabilization process a technology trial was performed. Three test panels were manufactured (3-stage, 1-stage and 1-stage with stabilized core). All test panels were manufactured in OoA process (Out of Autoclave). Panel surfaces were scanned with 3D scanner and compared with the reference CAD model. Both outer skin and inner skin were manufactured in Automated Fiber Placement Laboratory of Warsaw Institute of Aviation. composite
carbon fiber
sandwich structure
AFP
thermoset material
201932561-1310.2478/TAR-2019-0013Transactions on Aerospace Research
Maciej KarnyDETERMINATION OF IN-PLANE SHEAR PROPERTIESOF LAMINATE WITH V-NOTCH RAIL SHEAR TESTAND DIGITAL IMAGE CORRELATIONCOMPOSITE STRUCTURESThis article presents the results of the application of Digital Image Correlation (DIC) to measurements of in-plane shear modulus and strength of three different carbon fiber reinforced laminates. Three different approaches to shear strain calculations via DIC are evaluated and compared with standard strain gage measurements. Calculation of shear strain based on averaging DIC strain values of strain gages area in most cases yielded results closest to strain gages, while measurements based on single point strain measuring differed the most from strain gages. These results are attributed to shear strain distribution in the center area of the specimen. Thermoplastic matrix fabric reinforced composite had the lowest shear strength at 5% of shear strain, but the highest ultimate shear strength and strain at failure. Of thermosetting materials, laminate reinforced with unidirectional carbon fiber had shear modulus about 10% lower, than fabric reinforced laminate, but higher ultimate strength and strain at failure. This behavior is attributed to the presence of weaves in fabric reinforcing the laminate, causing shear stiffening of the material, but lowering its ability to deform under shear loading. Digital Image Correlation
in-plane shear
thermoplastic laminates
v-notch rail shear
2019325657-6510.2478/TAR-2019-0017Transactions on Aerospace Research
Rafał Szymański, Mateusz ZiębaManufacturing and Testing of Carbon Composite Samples Intended for AviationCOMPOSITE STRUCTURESThe paper presents the manufacturing technology and quality control of samples made of composite materials intended, inter alia, for aircraft elements. The samples are made from carbon fiber reinforced prepreg in a polymer matrix which is commonly used in the aerospace industry. The authors described the dimensional requirements for samples made of composite materials for strength testing, and the main stages of production which have a direct impact on the quality of composite samples. Also presented is the technological process of producing flat carbon composite panels for composite samples, cutting the produced panels with a CNC plotter, cutting the samples on a conventional milling machine, and surface treatment of the samples on a surface grinder. The machining parameters that were experientially found to be optimal for the milling and grinding of carbon samples are specified as well. Finally, the method of quality control of the ready composite samples is described and solutions are presented to improve the production of high-quality samples. carbon prepregs
composite technology
vacuum consolidation
strength testing
20173248107-11610.2478/TAR-2017-0024Transactions on Aerospace Research
Michał SokołowskiProcess of Preparing and Laying Carbon PrepregsCOMPOSITE STRUCTURESThis article contains information on the technological process involved in the production of a composite structure with carbon-epoxy prepregs including critical parameters of the process. The information in the publication shows respectively:
1. Using composite components for constructing the airframe,
2. ways of storing and preserving carbon prepregs on a matrix of thermosetting resins,
3. specific types of varying weave fabrics used in the prepregs,
4. way of preparing material for the process,
5. cutting tools,
6. preparing swage,
7. list of the most popular materials, their characteristics, pros and cons of their applications,
8. issues related to types of release agent,
9. parameters of selecting release agents in the process of manufacturing structures with carbon prepregs,
10. process of laying plies in a layered structure,
11. defects which result from improper material laying in swage,
12. preparing the structure for heating and technical parameters of the process.
carbon prepreg
composite material
release agents
swage
2017124627-3410.2478/TAR-2017-0003Transactions on Aerospace Research
Maciej KarnyThe influence of the fastener hole preparation method on the fastener pull-through process in a carbon compositeCOMPOSITE STRUCTURESThis article studies the pull-through resistance of a titanium carbon fibre-epoxy resin laminate fastener. Coupons with fastener holes made with different methods were compared – drilled, milled on a CNC plotter and special fibre application during laminate production. The tests were conducted according to the ASTM D7332 test standard. The studies showed that the fastener hole preparation method impacts the laminate’s resistance to fastener pull-through. Coupons with holes made with standard (drilling and milling) methods showed fastener pull-through resistance higher, on average, by 6.5% than in coupons with holes placed during plate production. Fastener work to rupture was also higher for coupons with milled and drilled holes. Microscopic observations in UV-light, using a fluorescent penetrant, showed differences in failure mechanisms between individual coupons, especially the lack of fibres in the 0° direction, in immediate vicinity to a hole prepared during laminate application. composites
fastener pull-through
ASTM D7332 standard
drilling
2017124645-5310.2478/TAR-2017-0005Transactions on Aerospace Research
Rafał SzymańskiQuality control process of manufactured composite structuresCOMPOSITE STRUCTURESThe paper includes a description of the composite material used in the aviation industry. It presents the technological development of composites in terms of their use in the most important elements of the aircraft structures, such as a spar and aircraft wing sheathing, which are subjected to high loads during operation. The type of the material implemented for production was listed and the most commonly occurred incompatibilities during the carbon pre-impregnate manufacture and transport were described.
The manufacture diagram of composite elements with a polymer matrix was presented and the quality control system carried out at each mentioned stage (material storage, defrosting, cutting of dies, structure forming, polymerisation) was discussed.
The methods of non-destructive tests of carbon laminates in a polymer matrix were also listed, describing the most effective of them, i.e. a method of ultrasonic tests.
The conclusions were drawn and the development possibilities of ultrasonic tests both in terms of quality improvement and reduction of time for detecting incompatibilities in composite structures were described.
pre-impregnate
composite technology
non-destructive tests with the use of an ultrasonic method
2017124695-10310.2478/TAR-2017-0009Transactions on Aerospace Research
Anna BonaTheoretical and experimental review of applied mechanical tests for carbon composites with thermoplastic polymer matrixCOMPOSITE STRUCTURESThis article has a theoretical and experimental character. It presents the characteristics of two main thermoplastics used in the aerospace industry – poly ether ether ketone (PEEK) and poly phenylene sulphide (PPS). The selected materials are compounds for the production of thermoplastic polymer matrix composites. The paper presents a literature review of the application of thermoplastic polymer matrix composite materials in aviation. Additionally, the paper focuses on the characteristics of carbon fibre-reinforced polymer (CFRP) which plays an important role in the production of aerospace components. Testing methods have been chosen on the basis of the type of composite matrix. The article contains the most important mechanical properties and general characteristics of thermoplastics used as a matrix for CFRP type composites used in the aerospace industry. Individual test procedures which allow for the evaluation of mechanical properties of composite materials on a thermoplastic polymer matrix, have been described. Mechanical tests such as static tensile test and bending of short beams were carried out in order to examine CFRP compositescarbon fibre composites,
PEEK,
PPS,
CFRP,
thermoplastics,
investigations of PEEK and PPS composites.
2019425755-7910.2478/TAR-2019-0023Transactions on Aerospace Research
Piotr Bajurko, Przemysław DobrzańskiExperimental Verification of Numerical Calculations with the Use of Digital Image CorrelationCOMPOSITE STRUCTURESThe article presents the results of research work performed under the TEBUK project, aiming primarily to develop a reference methodology for assessing the impact of damage on the strength of structures made of carbon epoxy prepregs. The tests described in the paper were concerned with a fragment of the structure (FS) of the TEBUK project demonstrator, made of carbon epoxy composite, with an artificial circular delamination measuring 40 mm in diameter. Numerical and experimental test of FS have been performed under quasi-static compression load. The buckling of the skin observed in the delamination area, as well as the propagation of the latter were investigated. The numerical calculations have been performed with the use of the commercially available MSC Marc/Mentat calculation suite based on the Finite Elements Methods. Results of the numerical calculations have been compared with experimental measurements made with the use of the Digital Image Correlation (DIC) method. The tests performed aimed to provide a preliminary verification of the numerical model. The results obtained have shown a very good correlation between the numerical and experimental results concerned with critical load levels at which stability of the layers separated by delamination is lost (buckling). The lack of convergence of the numerical model’s results after exceeding the critical load values has rendered it impossible to unequivocally compare the results concerned with propagation of the delamination area. digital image correlation
FEM
delamination
buckling
carbon-epoxy laminate
201822511-1510.2478/TAR-2018-0011Transactions on Aerospace Research
Robert JaśkiewiczImplementation of Automatic Sample and Composite Element Cutting TechnologiesCOMPOSITE STRUCTURESThe article presents the methodology of introducing automatic carbon fiber panel cutting technologies at the Composite Testing Laboratory of the Institute of Aviation. It describes the process of implementing the new cutting technology which boosts the efficiency of preparing composite samples for strength testing, with the requirements applicable to edge smoothness and dimension tolerances taken into consideration. It also reviews the literature concerned with three most popular composite material cutting methods: laser cutting, abrasive water jet cutting and machining, presenting the strong and the weak points of each one of them. After selecting the machining technology relying on a disc, cutting tests have been performed. Cutting discs coated with diamond particles, and carbon fiber panels were used during the tests. The tests were performed with the use of the INFOTEC CNC machine, with an adapter enabling the installation of cutting discs with the maximum diameter of 150 mm. composite cutting
automatic cutting
CNC cutting
carbon fiber machining
2018225124-3310.2478/TAR-2018-0013Transactions on Aerospace Research
Rafał SzymańskiNon-Destructive Testing of Thermoplastic Carbon Composite StructuresCOMPOSITE STRUCTURESThe article is in line with the contemporary interests of companies from the aviation industry.
It describes thermoplastic material and inspection techniques used in leading aviation companies.
The subject matter of non-destructive testing currently used in aircraft inspections of composite structures is approximated and each of the methods used is briefly described. The characteristics of carbon pre-impregnates in thermoplastic matrix are also presented, as well as types of thermoplastic materials and examples of their application in surface ship construction. The advantages, disadvantages and limitations for these materials are listed. The focus was put on the explanation of the ultrasonic method, which is the most commonly used method during the inspection of composite structures at the production and exploitation stage. Describing the ultrasonic method, the focus was put on echo pulse technique and
the use of modern Phased Array heads. Incompatibilities most frequently occurring and detected in composite materials with thermosetting and thermoplastic matrix were listed and described.
A thermoplastic flat composite panel made of carbon pre-impregnate in a high-temperature matrix (over 300°C), which was the subject of the study, was described. The results of non-destructive testing (ultrasonic method) of thermoplastic panel were presented and conclusions were drawn.
thermoplastic,
pre-impregnate,
non-destructive testing,
ultrasonic method,
Phased Array.
2020125834-5210.2478/TAR-2020-0003Transactions on Aerospace Research
František LöffelmannStress Distribution Investigation at the Tapered Sandwich EndingsCOMPOSITE STRUCTURESOne of the typical sandwich ending is tapered transition to a solid laminate, which causes significant stress distribution changes. The reviewed articles show that tapered area causes increase in the shear stress in the core, increase of the axial forces in the facesheets and local bending at the fork point, at points of the tapering angle change, and at ply drop positions. Most of the studies gave attention to the endings without reinforcing. During Erasmus+ internship at KTH 2D model of the tapered ending with reinforcing plies, various geometry and resin filler in the core tip was investigated to see the influence on the stress distribution. It was found that tension load case is not as critical as bending load case. Increasing of the solid laminate thickness, adding plies and inserting a short resin or adhesive filler into the core tip area lead to significant stress reduction, whereas in the transition point, from tapering to constant thickness sandwich, increasing radius is more efficient than reinforcing plies in regard to reduce stress concentration. Sandwich endings
Tapering
Ramp
Closeout
FEM
Filler
Ply drop
2017424964-8110.2478/TAR-2017-0029Transactions on Aerospace Research
Robert JaśkiewiczComparison of composite laminates machining methods and its influence on process temperature and edge qualityCOMPOSITE STRUCTURESThe article presents the description of technological trials and the results of three methods of machining carbon fiber reinforced composites panels. It also reviews the literature concerned heat affected zone in composites and its influence on material properties. As a part of the research, the cutting method using diamond coated saw was tested, as well as the milling method with two different types of carbide milling cutters. The processing of the panels was done using 4-axis CNC machine with special adapter for cutting discs in Composite Testing Laboratory (Center for Composite Technologies, Warsaw Institute of Aviation). The methods were compared in terms of machined edge quality and panel temperature during the processes. For this purpose, thermocouples were mounted into panels. Records from thermocouples were included. Edge quality and surface roughness have been checked by microscopic observation. Additionally, samples machined by each evaluated processing method were tested using differential scanning calorimetry (DSC). The method was used to determine the glass transition temperature of
the tested material. The article conclusions contain a comparison of three processing methods in terms of cutting quality, process temperature, processing method productivity as well as DSC tests results.
CFRP machining,
composite machining temperature,
DSC tests,
temperature tests.
2019425746-5410.2478/TAR-2019-0022Transactions on Aerospace Research
Przemysław DobrzańskiBonding of High Temperature Thermoplastic Carbon Composites with Resistance Welding TechniqueCOMPOSITE STRUCTURESThe article presents ‘state-of-the art’ on joining fibre reinforced thermoplastic composites with the use of resistance welding technique. Their welding process and potential difficulties connected with the process and quality control of a manufactured element are presented. The structure of a typical thermoplastic composite welding stand was also presented. The main welding technology elements were characterized: structure of the resistance element, implementation of the thermal process and pressure application required for joining materials. The paper also presents the required calibration ranges for a technological process with the use of strength test types SLS, DCB, SBS and nondestructive testing of joint with the ultrasonic method. thermoplastic composites
resistance welding
joining thermoplastic composites
201832521-1310.2478/TAR-2018-0018Transactions on Aerospace Research
Jakub Wilk, Radosław GuzikowskiValidation of numerical models used for designing the composite blade for ILX-27 rotorcraftCOMPOSITE STRUCTURESThe paper presents the validation procedure of the model used in the analysis of the composite blade for the rotor of the ILX-27 rotorcraft, designed and manufactured in the Institute of Aviation, by means of numerical analyses and tests of composite elements. Numerical analysis using finite element method and experimental studies of three research objects made of basic materials comprising the blade structure – carbon-epoxy laminate, glass-epoxy composite made of roving and foam filler – were carried out.
The elements were in the form of four-point bent beams, and for comparison of the results the deflection arrow values in the middle of the beam and axial deformations on the upper and lower surfaces were selected. The procedure allowed to adjust the discrete model to real objects and to verify and correct
the material data used in the strength analysis of the designed blade.
composites,
FEM modelling,
mechanical tests.
2019425723-3110.2478/TAR-2019-0020Transactions on Aerospace Research
Arnold JędralREVIEW OF TESTING METHODS DEDICATED FOR SANDWICH STRUCTURES WITH HONEYCOMB CORECOMPOSITESThis paper is a review of testing methods dedicated for sandwich type composite structures with honeycomb core. First, information about the composition of sandwich materials structures, their properties, types of core materials and applications in the industry is presented. Mechanical properties were compared in the case of different types of the core material. Later, tests methods needed to describe properties of those materials and normalization organizations which create them were mentioned. The testing methods were divided into two groups: mechanical and physicochemical tests. Mechanical properties are: compressive strength (two types of test), edge compressive strength, shear strength (in two directions) and tension strength (two types of test). Physicochemical properties are: material density, water migration, water absorption and thermal conductivity. Testing methods were described according to American Society for Testing and Materials (ASTM) standards. This article is based on professional literature and the author’s experience. mechanical properties
sandwich panel materials
honeycomb
Kevlar
Nomex
201922557-2010.2478/TAR-2019-0006Transactions on Aerospace Research
Mateusz Michalski, Wojciech KrauzeINFLUENCE OF HONEYCOMB CORE STABILIZATION ON COMPOSITE SANDWICH STRUCTURE GEOMETRYCOMPOSITESAuthors showed the influence of stabilization of the honeycomb core on shape of the composite sandwich test panel. Adhesive film laid on core ramps and cured with suitable cure cycle served as core stabilizer. Test panel geometry included different ramp angles (20° and 30°). To verify stabilization process a technology trial was performed. Three test panels were manufactured (3-stage, 1-stage and 1-stage with stabilized core). All test panels were manufactured in OoA process (Out of Autoclave). Panel surfaces were scanned with 3D scanner and compared with the reference CAD model. Both outer skin and inner skin were manufactured in Automated Fiber Placement Laboratory of Warsaw Institute of Aviation. composite
carbon fiber
sandwich structure
AFP
thermoset material
201932561-1310.2478/TAR-2019-0013Transactions on Aerospace Research
Maciej KarnyDETERMINATION OF IN-PLANE SHEAR PROPERTIESOF LAMINATE WITH V-NOTCH RAIL SHEAR TESTAND DIGITAL IMAGE CORRELATIONCOMPOSITESThis article presents the results of the application of Digital Image Correlation (DIC) to measurements of in-plane shear modulus and strength of three different carbon fiber reinforced laminates. Three different approaches to shear strain calculations via DIC are evaluated and compared with standard strain gage measurements. Calculation of shear strain based on averaging DIC strain values of strain gages area in most cases yielded results closest to strain gages, while measurements based on single point strain measuring differed the most from strain gages. These results are attributed to shear strain distribution in the center area of the specimen. Thermoplastic matrix fabric reinforced composite had the lowest shear strength at 5% of shear strain, but the highest ultimate shear strength and strain at failure. Of thermosetting materials, laminate reinforced with unidirectional carbon fiber had shear modulus about 10% lower, than fabric reinforced laminate, but higher ultimate strength and strain at failure. This behavior is attributed to the presence of weaves in fabric reinforcing the laminate, causing shear stiffening of the material, but lowering its ability to deform under shear loading. Digital Image Correlation
in-plane shear
thermoplastic laminates
v-notch rail shear
2019325657-6510.2478/TAR-2019-0017Transactions on Aerospace Research
Rafał Szymański, Mateusz ZiębaManufacturing and Testing of Carbon Composite Samples Intended for AviationCOMPOSITESThe paper presents the manufacturing technology and quality control of samples made of composite materials intended, inter alia, for aircraft elements. The samples are made from carbon fiber reinforced prepreg in a polymer matrix which is commonly used in the aerospace industry. The authors described the dimensional requirements for samples made of composite materials for strength testing, and the main stages of production which have a direct impact on the quality of composite samples. Also presented is the technological process of producing flat carbon composite panels for composite samples, cutting the produced panels with a CNC plotter, cutting the samples on a conventional milling machine, and surface treatment of the samples on a surface grinder. The machining parameters that were experientially found to be optimal for the milling and grinding of carbon samples are specified as well. Finally, the method of quality control of the ready composite samples is described and solutions are presented to improve the production of high-quality samples. carbon prepregs
composite technology
vacuum consolidation
strength testing
20173248107-11610.2478/TAR-2017-0024Transactions on Aerospace Research
Michał SokołowskiProcess of Preparing and Laying Carbon PrepregsCOMPOSITESThis article contains information on the technological process involved in the production of a composite structure with carbon-epoxy prepregs including critical parameters of the process. The information in the publication shows respectively:
1. Using composite components for constructing the airframe,
2. ways of storing and preserving carbon prepregs on a matrix of thermosetting resins,
3. specific types of varying weave fabrics used in the prepregs,
4. way of preparing material for the process,
5. cutting tools,
6. preparing swage,
7. list of the most popular materials, their characteristics, pros and cons of their applications,
8. issues related to types of release agent,
9. parameters of selecting release agents in the process of manufacturing structures with carbon prepregs,
10. process of laying plies in a layered structure,
11. defects which result from improper material laying in swage,
12. preparing the structure for heating and technical parameters of the process.
carbon prepreg
composite material
release agents
swage
2017124627-3410.2478/TAR-2017-0003Transactions on Aerospace Research
Maciej KarnyThe influence of the fastener hole preparation method on the fastener pull-through process in a carbon compositeCOMPOSITESThis article studies the pull-through resistance of a titanium carbon fibre-epoxy resin laminate fastener. Coupons with fastener holes made with different methods were compared – drilled, milled on a CNC plotter and special fibre application during laminate production. The tests were conducted according to the ASTM D7332 test standard. The studies showed that the fastener hole preparation method impacts the laminate’s resistance to fastener pull-through. Coupons with holes made with standard (drilling and milling) methods showed fastener pull-through resistance higher, on average, by 6.5% than in coupons with holes placed during plate production. Fastener work to rupture was also higher for coupons with milled and drilled holes. Microscopic observations in UV-light, using a fluorescent penetrant, showed differences in failure mechanisms between individual coupons, especially the lack of fibres in the 0° direction, in immediate vicinity to a hole prepared during laminate application. composites
fastener pull-through
ASTM D7332 standard
drilling
2017124645-5310.2478/TAR-2017-0005Transactions on Aerospace Research
Rafał SzymańskiQuality control process of manufactured composite structuresCOMPOSITESThe paper includes a description of the composite material used in the aviation industry. It presents the technological development of composites in terms of their use in the most important elements of the aircraft structures, such as a spar and aircraft wing sheathing, which are subjected to high loads during operation. The type of the material implemented for production was listed and the most commonly occurred incompatibilities during the carbon pre-impregnate manufacture and transport were described.
The manufacture diagram of composite elements with a polymer matrix was presented and the quality control system carried out at each mentioned stage (material storage, defrosting, cutting of dies, structure forming, polymerisation) was discussed.
The methods of non-destructive tests of carbon laminates in a polymer matrix were also listed, describing the most effective of them, i.e. a method of ultrasonic tests.
The conclusions were drawn and the development possibilities of ultrasonic tests both in terms of quality improvement and reduction of time for detecting incompatibilities in composite structures were described.
pre-impregnate
composite technology
non-destructive tests with the use of an ultrasonic method
2017124695-10310.2478/TAR-2017-0009Transactions on Aerospace Research
Anna BonaTheoretical and experimental review of applied mechanical tests for carbon composites with thermoplastic polymer matrixCOMPOSITESThis article has a theoretical and experimental character. It presents the characteristics of two main thermoplastics used in the aerospace industry – poly ether ether ketone (PEEK) and poly phenylene sulphide (PPS). The selected materials are compounds for the production of thermoplastic polymer matrix composites. The paper presents a literature review of the application of thermoplastic polymer matrix composite materials in aviation. Additionally, the paper focuses on the characteristics of carbon fibre-reinforced polymer (CFRP) which plays an important role in the production of aerospace components. Testing methods have been chosen on the basis of the type of composite matrix. The article contains the most important mechanical properties and general characteristics of thermoplastics used as a matrix for CFRP type composites used in the aerospace industry. Individual test procedures which allow for the evaluation of mechanical properties of composite materials on a thermoplastic polymer matrix, have been described. Mechanical tests such as static tensile test and bending of short beams were carried out in order to examine CFRP compositescarbon fibre composites,
PEEK,
PPS,
CFRP,
thermoplastics,
investigations of PEEK and PPS composites.
2019425755-7910.2478/TAR-2019-0023Transactions on Aerospace Research
Piotr Bajurko, Przemysław DobrzańskiExperimental Verification of Numerical Calculations with the Use of Digital Image CorrelationCOMPOSITESThe article presents the results of research work performed under the TEBUK project, aiming primarily to develop a reference methodology for assessing the impact of damage on the strength of structures made of carbon epoxy prepregs. The tests described in the paper were concerned with a fragment of the structure (FS) of the TEBUK project demonstrator, made of carbon epoxy composite, with an artificial circular delamination measuring 40 mm in diameter. Numerical and experimental test of FS have been performed under quasi-static compression load. The buckling of the skin observed in the delamination area, as well as the propagation of the latter were investigated. The numerical calculations have been performed with the use of the commercially available MSC Marc/Mentat calculation suite based on the Finite Elements Methods. Results of the numerical calculations have been compared with experimental measurements made with the use of the Digital Image Correlation (DIC) method. The tests performed aimed to provide a preliminary verification of the numerical model. The results obtained have shown a very good correlation between the numerical and experimental results concerned with critical load levels at which stability of the layers separated by delamination is lost (buckling). The lack of convergence of the numerical model’s results after exceeding the critical load values has rendered it impossible to unequivocally compare the results concerned with propagation of the delamination area. digital image correlation
FEM
delamination
buckling
carbon-epoxy laminate
201822511-1510.2478/TAR-2018-0011Transactions on Aerospace Research
Robert JaśkiewiczImplementation of Automatic Sample and Composite Element Cutting TechnologiesCOMPOSITESThe article presents the methodology of introducing automatic carbon fiber panel cutting technologies at the Composite Testing Laboratory of the Institute of Aviation. It describes the process of implementing the new cutting technology which boosts the efficiency of preparing composite samples for strength testing, with the requirements applicable to edge smoothness and dimension tolerances taken into consideration. It also reviews the literature concerned with three most popular composite material cutting methods: laser cutting, abrasive water jet cutting and machining, presenting the strong and the weak points of each one of them. After selecting the machining technology relying on a disc, cutting tests have been performed. Cutting discs coated with diamond particles, and carbon fiber panels were used during the tests. The tests were performed with the use of the INFOTEC CNC machine, with an adapter enabling the installation of cutting discs with the maximum diameter of 150 mm. composite cutting
automatic cutting
CNC cutting
carbon fiber machining
2018225124-3310.2478/TAR-2018-0013Transactions on Aerospace Research
František LöffelmannStress Distribution Investigation at the Tapered Sandwich EndingsCOMPOSITESOne of the typical sandwich ending is tapered transition to a solid laminate, which causes significant stress distribution changes. The reviewed articles show that tapered area causes increase in the shear stress in the core, increase of the axial forces in the facesheets and local bending at the fork point, at points of the tapering angle change, and at ply drop positions. Most of the studies gave attention to the endings without reinforcing. During Erasmus+ internship at KTH 2D model of the tapered ending with reinforcing plies, various geometry and resin filler in the core tip was investigated to see the influence on the stress distribution. It was found that tension load case is not as critical as bending load case. Increasing of the solid laminate thickness, adding plies and inserting a short resin or adhesive filler into the core tip area lead to significant stress reduction, whereas in the transition point, from tapering to constant thickness sandwich, increasing radius is more efficient than reinforcing plies in regard to reduce stress concentration. Sandwich endings
Tapering
Ramp
Closeout
FEM
Filler
Ply drop
2017424964-8110.2478/TAR-2017-0029Transactions on Aerospace Research
Robert JaśkiewiczComparison of composite laminates machining methods and its influence on process temperature and edge qualityCOMPOSITESThe article presents the description of technological trials and the results of three methods of machining carbon fiber reinforced composites panels. It also reviews the literature concerned heat affected zone in composites and its influence on material properties. As a part of the research, the cutting method using diamond coated saw was tested, as well as the milling method with two different types of carbide milling cutters. The processing of the panels was done using 4-axis CNC machine with special adapter for cutting discs in Composite Testing Laboratory (Center for Composite Technologies, Warsaw Institute of Aviation). The methods were compared in terms of machined edge quality and panel temperature during the processes. For this purpose, thermocouples were mounted into panels. Records from thermocouples were included. Edge quality and surface roughness have been checked by microscopic observation. Additionally, samples machined by each evaluated processing method were tested using differential scanning calorimetry (DSC). The method was used to determine the glass transition temperature of
the tested material. The article conclusions contain a comparison of three processing methods in terms of cutting quality, process temperature, processing method productivity as well as DSC tests results.
CFRP machining,
composite machining temperature,
DSC tests,
temperature tests.
2019425746-5410.2478/TAR-2019-0022Transactions on Aerospace Research
Przemysław DobrzańskiBonding of High Temperature Thermoplastic Carbon Composites with Resistance Welding TechniqueCOMPOSITESThe article presents ‘state-of-the art’ on joining fibre reinforced thermoplastic composites with the use of resistance welding technique. Their welding process and potential difficulties connected with the process and quality control of a manufactured element are presented. The structure of a typical thermoplastic composite welding stand was also presented. The main welding technology elements were characterized: structure of the resistance element, implementation of the thermal process and pressure application required for joining materials. The paper also presents the required calibration ranges for a technological process with the use of strength test types SLS, DCB, SBS and nondestructive testing of joint with the ultrasonic method. thermoplastic composites
resistance welding
joining thermoplastic composites
201832521-1310.2478/TAR-2018-0018Transactions on Aerospace Research
Jakub Wilk, Radosław GuzikowskiValidation of numerical models used for designing the composite blade for ILX-27 rotorcraftCOMPOSITESThe paper presents the validation procedure of the model used in the analysis of the composite blade for the rotor of the ILX-27 rotorcraft, designed and manufactured in the Institute of Aviation, by means of numerical analyses and tests of composite elements. Numerical analysis using finite element method and experimental studies of three research objects made of basic materials comprising the blade structure – carbon-epoxy laminate, glass-epoxy composite made of roving and foam filler – were carried out.
The elements were in the form of four-point bent beams, and for comparison of the results the deflection arrow values in the middle of the beam and axial deformations on the upper and lower surfaces were selected. The procedure allowed to adjust the discrete model to real objects and to verify and correct
the material data used in the strength analysis of the designed blade.
composites,
FEM modelling,
mechanical tests.
2019425723-3110.2478/TAR-2019-0020Transactions on Aerospace Research
Rafał Chatys, Anna Stefańska, Krzysztof Piernik, Konrad StefańskiEstimation of Strength Parameters of Aviation Products Made of Polymer Composites Based on Markov Chain TheoryCOMPOSITESThe study investigates the fatigue strength of a component made of a glass composite material with polyester matrix, manufactured using a contact method (I) and by vacuum bagging (II). Modeling was carried out only for composite material II, due to significant spread of the strength of the composite material manufactured by contact lamination I, which means that such a material does not guarantee repeatability of the test results. Estimation of the composite material fatigue strength and residual strength was performed using a mathematical model based on the Markov chain theory. The model assumed that the material failure occurs at certain critical microvolume of the components operating within the plastic range. Observed relationships between the probability values and the distribution parameters for the static strength of the composite components, as well as the load values allow for deriving a fatigue curve equation. Obtained results are presented in the tables. composite material
composite testing
fatigue strength
residual strength
Markov’s theory
2017224719-3010.2478/TAR-2017-0012Transactions on Aerospace Research
Marcelina Bobrowska, Michał Barcikowski, Radosław RybczyńskiResearch of Dependence of the Damage Area on Tow Width on Filament-Wound Composite TubesCOMPOSITESThis paper explores the effect of tow width on the damage area produced by high velocity impacts on glass fiber/epoxy composite structures made by filament winding. The subject of the research were a four-layered composite tubes that have been designed using matrix method. The method was used to select mosaic patterns with different rest of the winding stroke and number of interlaces, which are places of stress concentration and which affect the strength of the composite. The narrowest (5 mm) and the widest (17 mm) tow width available was chosen. Composite filament-wound structures were subjected to a high velocity impact by a 2.0 g spherical hardened steel impactor propelled to a velocity of 140 ÷ 170 m/s using a gas gun. It was observed that dependence of the damage area on tow width on filament-wound composite tubes is possible. Filament-wound composite structures
impact damage
ballistic impact
filament winding
201712467-1410.2478/tar-2017-0001Transactions on Aerospace Research
Piotr BajurkoMODELLING OF THE AEROSPACE STRUCTURE DEMONSTRATOR SUBCOMPONENTCompositesCarbon-epoxy composite materials, due to their high strength in relation to mass, are increasingly used in the construction of aircraft structures, however, they are susceptible to a number of damages. One of the most common is delamination, which is a serious problem in the context of safe operation of such structures. As part of the TEBUK project, the Institute of Aviation has developed a methodology for forecasting the propagation of delamination. In order to validate the proposed method, an aerial structure demonstrator, modelled on the horizontal stabilizer of the I-23 Manager aircraft, was carried out. However, in order to carry out the validation, it was necessary to "simplify" the demonstrator model. The paper presents a numerical analysis conducted in order to separate from the TEBUK demonstrator model a fragment of the structure, which was used to study the delamination area, as an equivalent of the whole demonstrator. Subcomponent selection was carried out in several stages, narrowing down the analysed area covering delamination in subsequent steps and verifying the compliance of specific parameters with the same parameters obtained in a full demonstrator model. The parameters compared were: energy release rate values on the delamination front line and strain values in the delamination area. The numerical analyses presented in the paper were performed with the use of the MSC.Marc/Mentat calculation package. As a result of the analyses, a fragment of the structure was selected, which allows to significantly reduce the time and labour consumption of the production of the studied object, as well as to facilitate experimental research. FEM
delamination
buckling
carbon-epoxy composite
2019125437-5210.2478/TAR-2019-0004Transactions on Aerospace Research
Rafał SzymańskiNon-Destructive Testing of Thermoplastic Carbon Composite StructuresCOMPOSITESThe article is in line with the contemporary interests of companies from the aviation industry.
It describes thermoplastic material and inspection techniques used in leading aviation companies.
The subject matter of non-destructive testing currently used in aircraft inspections of composite structures is approximated and each of the methods used is briefly described. The characteristics of carbon pre-impregnates in thermoplastic matrix are also presented, as well as types of thermoplastic materials and examples of their application in surface ship construction. The advantages, disadvantages and limitations for these materials are listed. The focus was put on the explanation of the ultrasonic method, which is the most commonly used method during the inspection of composite structures at the production and exploitation stage. Describing the ultrasonic method, the focus was put on echo pulse technique and
the use of modern Phased Array heads. Incompatibilities most frequently occurring and detected in composite materials with thermosetting and thermoplastic matrix were listed and described.
A thermoplastic flat composite panel made of carbon pre-impregnate in a high-temperature matrix (over 300°C), which was the subject of the study, was described. The results of non-destructive testing (ultrasonic method) of thermoplastic panel were presented and conclusions were drawn.
thermoplastic,
pre-impregnate,
non-destructive testing,
ultrasonic method,
Phased Array.
2020125834-5210.2478/TAR-2020-0003Transactions on Aerospace Research
Albert Zajdel, Cezary Szczepański, Mariusz Krawczyk, Jerzy Graffstein, Piotr MasłowskiSelected Aspects of the Low Level Automatic Taxi Control System ConceptControl systemsTaxiing of manned and remotely piloted aircraft is still performed by pilots without using a system of automatic control of direction and speed. Several reasons have emerged in recent years that make the automation of taxiing an important design challenge. The reasons are: decreased airport capacity due to the growing number of aircraft, poor ground operation conditions during poor visibility conditions, an increase in workload of pilots and air traffic controllers and the integration of simultaneous ground operations of manned and remotely piloted air vehicles. This paper presents selected aspects of the concept of a Low Level Automatic Taxi Control System. In particular, it emphasizes the means of controlling an aircraft during taxiing, accuracy requirements of the system and proposes control techniques. The resulting controller of the system is adaptable for different aircrafts. The actuators and their mechanical connections to available controls are the aircraft specific part and are designed for the particular type – in this case – a general aviation light airplane. taxi
taxiing
automatic taxi
taxi control system
2017224769-7910.2478/TAR-2017-0016Transactions on Aerospace Research
Valentyn UchaninEnhanced Eddy Current techniques for detection of surface-breaking cracks in aircraft structures.DiagnosticsWell-timed detection of the defects (e.g., fatigue cracks and corrosive damages) in aircraft structures is the question of vital importance. Periodic in-service non-destructive inspection (NDI) is necessary to prevent expensive aircraft breakdowns during in-service life. Eddy current (EC) NDI method have many advantages for in-service aircraft inspection due to high mobility and the possibility to detect fatigue cracks without direct contact with the inspected surface (even through a protective coating without removal). Last decades some enhanced EC techniques were developed for aircraft in-service inspection in the Karpenko Physico-Mechanical Institute of National Academy of Sciences (Lviv) in collaboration with Ukrainian and foreign aircraft companies.

Proposed earlier EC efficiency coefficient was applied for the selection of the ferrite-core EC probe parameters. Investigations concerned with the crack detectability for single-coil EC probes of different sizes were carried out to improve the inspection procedures. The sensitivity of the developed single-coil EC probe was experimentally investigated. The possibility to distinguish the signals associated with detected defect and lift-off was shown. The new inspection procedure was proposed for full suppression of the noise concerned with the rivet edge influence.

The high-frequency EC flaw detector of Leotest VD 3.03 type based on self-generator mode and miniature single-coil EC probes application was developed for detection of the surface-breaking fatigue cracks. The original scheme of double-circuit self-generator with intermittent oscillations was invented and investigated. The pulse-repetition frequency of high-frequency oscillations was used as an informative parameter. The important feature of the developed self-generating scheme is the effective suppression of the lift-off influence (the changes of the clearance between the EC probe and the inspected object surface during the scanning).

Developed EC flaw detectors of Leotest VD 3.03 type and inspection procedures were successfully implemented into the maintenance practice for detection of the fatigue cracks initiated in the wing and the fuselage structures and aviation engines in many companies such as ANTONOV AIRCRAFT, Lviv State Aircraft Repair Plant, Konotop aircraft repair plant «AVIAKON», Ukrainian International Airlines, MOTOR-SICH, State Enterprise “IVCHENKO-PROGRESS”, etc.
eddy current (EC)
EC flaw detector
single-coil EC probe
complex plane
aircraft structure
fatigue crack
self-generating scheme
lift-off
202112621-1410.2478/TAR-2021-0001Transactions on Aerospace Research
Iuliia Lysenko, Volodymyr Eremenko, Yurii Kuts, Anatoliy Protasov, Valentin UchaninAdvanced Signal Processing Methods for Inspection of Aircraft Structural MaterialsDiagnosticsAircraft, their assemblies, and units must provide high durability and reliability, and maintain mechanical and technological characteristics throughout the life span of the aircraft. Different elements of aircraft structures work under mechanical loads, over a wide temperature range, with varying degrees of exposure to corrosive environments. Aircraft structural materials have a variation in the characteristics values and require the various testing methods for their inspection.
In many NDT methods applied in aviation materials testing, signals that could be represented by
a narrowband processes model are used. Known methods of their processing are focused on determining and analyzing the signals amplitude characteristics, but the information resource contained in phase characteristics is not used.
In the article, the methodology for signal processing and determining phase characteristics in the time domain are discussed. It is based on the combination of the discrete Hilbert transform and the deterministic and statistical methods of the phase measurement. There are given examples of the application of
the methodology for pulsed eddy current testing of electrically conductive materials and products, ultrasonic thickness measurement of products made of materials have significant ultrasonic attenuation, the realization impulse variant of acoustic impedance flaw detection of products made of composite materials. The examples have shown that the proposed signal processing methodology enables to determine new information parameters and signal characteristics for the industry, and extend the scope of known NDT methods.
signal processing methodology,
signal characteristics,
information parameters,
aviation materials testing
2020225927-3510.2478/TAR-2020-0008Transactions on Aerospace Research
Valentyn UchaninDetection of the Fatigue Cracks Initiated Near the Rivet Holes by Eddy Current Inspection TechniquesDiagnosticsEddy current (EC) method is considered as most applicable for in-service detection of fatigue subsurface cracks initiated in aircraft multilayer structures near the rivet holes. At the same time,
the successful solution of this problem is obstructed by additional noise created by defect-free rivets.
All EC inspection techniques for the detection of subsurface cracks around the rivets can be classified into three main groups: 1) static mode – carried out by placing the EC probe concentrically on the rivet head; 2) rotational mode – when the EC probe is rotated around the rivet axle and 2) sliding mode – performed by the movement of EC probe along the rivet line or near it. All these approaches have some advantages and limitations. In this study, known EC techniques for the detection of cracks in multilayer aircraft structures are analyzed. New advanced EC techniques for the detection of fatigue cracks in internal layers of the riveted structures based on different types (ring, sliding, and rotational) probes are presented.
The static EC method with developed low-height ring-type probe creates the possibility to detect cracks in the difficult of access areas. The possibility to estimate the length of detected cracks by a ring-type probe is shown. The proposed rotational remote field EC probe can detect as small as 1.0 mm long cracks under the button-head rivet and 2 mm thick upper skin with a high signal-to-noise ratio. Therefore, in many aircraft structures, fatigue cracks will be detected before a critical threshold achieved. New EC sliding techniques based on remote field and double differential probes were proposed for the rapid detection of cracks in internal layers of riveted aircraft structures. Remote-field EC probe for reliable detection of fatigue cracks in third and fourth layers of five-layer units was proposed. Another sliding technique based on a double differential EC probe gives the possibility to detect transverse cracks in
the second layer without the rivet row area access. The main advantage of developed techniques is high inspection reliability due to the possibility to discriminate the signals created by cracks and defect-free rivets. Presented inspection procedures include the selective signal analysis in the complex plane diagram. Proposed EC inspection techniques were successfully implemented into the aircraft maintenance practice.
eddy current (EC),
EC probe,
rivet,
multilayer aircraft structure,
fatigue crack,
operational frequency
2020225947-5810.2478/TAR-2020-0010Transactions on Aerospace Research
Rafał SzymańskiNon-Destructive Testing of Thermoplastic Carbon Composite StructuresDiagnosticsThe article is in line with the contemporary interests of companies from the aviation industry.
It describes thermoplastic material and inspection techniques used in leading aviation companies.
The subject matter of non-destructive testing currently used in aircraft inspections of composite structures is approximated and each of the methods used is briefly described. The characteristics of carbon pre-impregnates in thermoplastic matrix are also presented, as well as types of thermoplastic materials and examples of their application in surface ship construction. The advantages, disadvantages and limitations for these materials are listed. The focus was put on the explanation of the ultrasonic method, which is the most commonly used method during the inspection of composite structures at the production and exploitation stage. Describing the ultrasonic method, the focus was put on echo pulse technique and
the use of modern Phased Array heads. Incompatibilities most frequently occurring and detected in composite materials with thermosetting and thermoplastic matrix were listed and described.
A thermoplastic flat composite panel made of carbon pre-impregnate in a high-temperature matrix (over 300°C), which was the subject of the study, was described. The results of non-destructive testing (ultrasonic method) of thermoplastic panel were presented and conclusions were drawn.
thermoplastic,
pre-impregnate,
non-destructive testing,
ultrasonic method,
Phased Array.
2020125834-5210.2478/TAR-2020-0003Transactions on Aerospace Research
Yevhen MartseniukSteady and transient thermal state of turbine disc estimation for life time monitoring.DiagnosticsIn connection with increasing intensification of the working process in a gas turbine engine and increasing requirements for economy, the problem of defining and monitoring the main parts lifetime is becoming more vital. Modern algorithms of the monitoring systems are based on taking into account
the levels of part temperature and total equivalent stress throughout the flight cycle. Thermal and stress-strain states of the critical zones of the main parts are determined on the basis of information received from the sensors installed in the engine gas path. Turbine disks are located in the internal cavities of
the engine and are cooled by air from the compressor. However, in some designs, the disk cavity can be separated from the place of cooling air bleed by several stages of non-contact labyrinth seals, which will lead to some delay in changing the parameters of the cooling air flow when changing the engine operating mode. It has been observed that if this situation is not taken into account, it can lead to significant errors (more than 40%) in determining the lifetime for the peripheral zone of the disk. At the same time, this error is minimal for the hub and the middle zone of the disk, and the existing monitoring algorithms can be used.
lifetime,
monitoring,
thermal-stress state,
model.
2020326021-2910.2478/TAR-2020-0014Transactions on Aerospace Research
Jan Kotlarz, Natalia ZalewskaTHE POSSIBILITY OF ULTRAVIOLET ENCELADUS’ OBSERVATIONS FROM STRATOSPHERIC BALLOONSEARTHStratospheric balloons are very important sources for space and terrestrial observation experiments in many disciplines. Instruments developed for astrophysical measurements are usually reusable. It is also possible to observe both hemispheres including observations from the polar and equatorial regions for thirty days or even longer. On the other hand the UV atmospheric transmittance window was used for the astrophysical observations less often than visible optical bands. At the end of the 2017 there are a few scientific groups working on near-UV or UV spectrographs and cameras for balloon flights. stratospheric balloons
Enceladus
ultraviolet
water ice
tholin
2019125417-2710.2478/TAR-2019-0002Transactions on Aerospace Research
Hubert SkonecznyPREPARATION AND IMPLEMENTATION OF A TEST FLIGHT OF LIGHTWEIGHT, UNMANNED STRATOSPHERIC BALLOON WITH GOPRO CAMERA MOUNTED AND ANALYSIS OF ACQUIRED MATERIALEARTHPublication contains a description of the preparation and the implementation of a test flight of a stratospheric balloon with a mounted camera GoPro Hero3. Description includes: used equipment, its parameters, role in the success of the mission and the difficulties and limitations that the project team encountered during the preparation and implementation of the flight. The mission was attended by a team of six engineers and scientists from the Remote Sensing Division, who were also involved in the implementation of the HESOFF project. One of the main goals of the HESOFF project was to obtain aerial images on the Krotoszyńska Plate (woj. wielkopolskie) using the Unmanned Aerial Vehicle (UAV) and to carry out remote monitoring of oak stands. The primary goal of an experimental balloon flight was to check the technical operational capability and gain experience in planning and implementing this type of project. During the balloon raising, the video material was acquired in the form of a recording, which later was analyzed. On the basis of the collected information, the conclusions regarding the possibility of implementing a long endurance flight in the stratosphere, illustrating (using a multisensor platform) research surfaces of the HESOFF project were presented. The stages of implementation of the presented mission were divided into following parts: preparation of the flight with the completion of equipment and necessary documents (flight permission), proper flight realization, understood as the release of the balloon and identification of the place where the equipment landed, as well as analysis and presentation of the results. stratospheric balloon
photogrammetric flight
GPS
Unmanned Aerial Vehicle
2019225521-3210.2478/TAR-2019-0007Transactions on Aerospace Research
Marcin Spiralski, Karol Bęben, Wojciech Konior, Dawid CieślińskiHigh Altitude Ballooning as an Atmospheric Sounding System in the Pre-Flight Procedures of ILR-33 AmberEARTHThe paper presents research on the near real-time atmospheric sounding system. The main objective of the research was the development and testing of the weather sounding system based on a weather balloon. The system contains a redundant system of radiosondes, a lifting platform containing weather balloon and a holding system as well as ground station. Several tests of the system were performed in August and September 2019. Altitude, reliability, resistance to weather conditions and data convergence were tested. During tests, new procedures for such missions were developed. The final test was performed for the ILR-33 Amber Rocket as a part of pre-launch procedures. The test was successful and allowed to use acquired atmospheric data for further processing. Several post-tests conclusions were drawn.
The altitude of sounding by a weather balloon depends mostly on weather conditions, the amount of gas pumped and the weight of a payload. The launching place and experience of the crew play an important role in the final success of the mission, as well.
weather balloon,
unmanned free balloon, a
tmosphere sounding,
radiosonde,
remote sensing,
Earth observation
2020125866-7710.2478/TAR-2020-0005Transactions on Aerospace Research
Łukasz Jeziorek, Krzysztof Szafran, Paweł SkalskiHeat Transfer Determined by the Temperature Sensitive Paint MethodExperimental methodsThe paper presents practical aspects of determining the amount of heat flow by measuring the distribution of surface temperature using the Temperature Sensitive Paint (TSP) method. The quantity measured directly with TSP is the intensity of the excited radiation, which is then converted to surface temperature. The article briefly presents three different methods for determining the heat transfer coefficient. Each of these methods is based on a separate set of assumptions and significantly influences the construction of the measuring station. The advantages of each of the presented methods are their individual properties, allowing to improve accuracy, reduce the cost of testing or the possibility of using them in tests of highly complex objects. For each method a mathematical model used to calculate the heat transfer coefficient is presented. For the steady state heat transfer test method that uses a heater of constant and known thermal power, examples of the results of our own research are presented, together with a comparison of the results with available data and a discussion of the accuracy of the results obtained. temperature sensitive paint
TSP
temperature measurement
heat transfer coefficient
HTC
2018425345-5710.2478/TAR-2018-0029Transactions on Aerospace Research
William J. Deitrick, Wit StryczniewiczDevelopment and Testing of Data Reduction Software for Measurements Using Pressure Sensitive PaintsExperimental methodsThe paper concentrates on post-processing of data necessary for pressure measurements using Pressure Sensitive Paints (PSP). The purpose of the study was to develop and test procedures for extraction of the surface pressure distribution from the images captured during PSP tests. The core issues addressed were reduction of the influence of model movement and deformation during wind tunnel run and synchronization between conventional pressure tap measurements and PSP data, necessary for in-situ calibration. In the course of the studies, two approaches on image registration were proposed: the first based on geometric transformation of control points pairs with cross-correlation tuning and the second based on similarity finding and estimation of geometric transformation of the images. Performance of the developed algorithm was tested with use of experimental set-up allowing for controlled movement of the imagined target with micrometer resolution. Both of the proposed approaches to PSP image resection proved to perform well. After testing of the software, the PSP system was used for determination of the pressure field on flat plate exposed to impinging jet. The presented procedures and results can be useful for research groups developing in-house PSP measurements systems for wind tunnel tests and internal flow investigations. Pressure Sensitive Paint
image registration
impinging jet
2018425368-8010.2478/TAR-2018-0031Transactions on Aerospace Research
Łukasz Jeziorek, Patryk WideraTemperature measurements using thermal sensitive paintExperimental methodsArticle highlights practical issues concerning temperature measurements using thermal sensitive paint (abbrev. TSP). TSP paint after blue light excitation emits red light with intensity dependent on its temperature. Temperature measurements are preceded with paint calibration, according to exact experiment conditions. Purpose of calibration is to find transfer function between intensity of emitted radiation and surface temperature. To achieve this goal, special computational procedure is implemented. Devices and methodology used for paint calibration are briefly described as well as measuring sample preparation process. Short description is devoted to the procedure for calculation temperature using recorded intensity. Results obtained during calibration are presented. Final conclusions about perspective of using thermal sensitive paint in laboratory are presented, as well as advantages and disadvantages of TSP method versus other methods currently used in temperature measurements. Thermal sensitive paint
TSP
temperature measurement
2018325237-4810.2478/TAR-2018-0021Transactions on Aerospace Research
Łukasz KędzierskiCompressed Air Supply and Distribution System for Aviation Laboratories and Wind TunnelsExperimental methodsThe purpose of this text is to demonstrate an operation of a compressed air system designed for high air flow laboratories and wind tunnels. Development of such air system is a challenge due to unusual requirements (simultaneous supply of several users having different requirements and necessity to provide extremely high flows) which have to be address by means of adequate compressed air storage capacity and sophisticated control system. Each stage of the design process is going to be described, focusing on the selection of air compressors, air receivers and air dryers, followed by an insight into a development of the control system. The air system being described in this paper was successfully implemented at the Institute of Aviation in Warsaw improving the quality of the compressed air supply and simplifying the research planning. compressed
air
laboratory
wind
tunnel
2018125026-3510.2478/TAR-2018-0003Transactions on Aerospace Research
Wit StryczniewiczQuantitative Visualisation of Compressible FlowsExperimental methodsThe paper demonstrates the feasibility of quantitative flow visualisation methods for investigation of transonic and supersonic flows. Two methods and their application for retrieving compressible flow field properties has been described: Background Oriented Schlieren (BOS) and Particle Image Velocimetry (PIV). Recently introduced BOS technique extends the capabilities of classical Schlieren technique by use of digital image processing and allow to measure density gradients field. In the presented paper a review of applications of BOS technique has been presented. The PIV is well established technique for whole field velocity measurements. This paper presents application of PIV for determination of the shock wave position above airfoil in transonic flow regime. The study showed that application of quantitative flow visualisation techniques allows to gain new insights on the complex phenomenon of supersonic and transonic flow over airfoils like shock-boundary layer interaction and shock induced flow separation. compressible fluid flow
flow visualisation
wind tunnel studies
Particle Image Velocimetry
Background Oriented Schlieren
20181250137-14510.2478/TAR-2018-0009Transactions on Aerospace Research
Marek Idzikowski, Wojciech MiksaGround and In-Fligh Testing of Cooling Efficiency of Turboprop Engine CompartmentFlight testingThis article presents selected results of I-31T propulsion tests, obtained in the framework of EU project ESPOSA (Efficient Systems and Propulsion for Small Aircraft). I-31T aircraft, as a testbed, was fitted with 180 kW turboprop engine TP100. The scope of the work include results of ground and in-flight tests of engine compartment cooling suitability. The purpose of the cooling tests was to prove that temperatures of the propulsion components are within limits set by the engine manufacturer for the engine type in the most disadvantageous conditions on the ground and in flight up to aircraft maximum altitude, maximum ambient temperature and after standard engine shutdown. Engine oil cooling is beyond the scope of this work. light aircraft
in-flight tests
turboprop engine installation
turboprop engine integration in airframe
engine compartment cooling
2018125017-2510.2478/TAR-2018-0002Transactions on Aerospace Research
Marek Idzikowski, Wojciech MiksaFlight tests of turboprop engine with reverse air intake systemFlight testsThis work presents selected results of I-31T propulsion flight tests, obtained in the framework of ESPOSA (Efficient Systems and Propulsion for Small Aircraft) project. I-31T test platform was equipped with TP100, a 180 kW turboprop engine. Engine installation design include reverse flow inlet and separator, controlled from the cockpit, that limited ingestion of solid particulates during ground operations. The flight tests verified proper air feed to the engine with the separator turned on and off. The carried out investigation of the intake system excluded possibility of hazardous engine operation, such as compressor stall, surge or flameout and potential airflow disturbance causing damaging vibration of the engine body. Finally, we present evaluation of total power losses associated with engine integration with the airframe. light aircraft
flight tests
turboprop engine installation
turboprop engine integration
reverse air flow to engine
2018325226-3610.2478/TAR-2018-0020Transactions on Aerospace Research
Kamila Stryczniewicz, Przemysław DrężekCFD approach to modelling hydrodynamic characteristics of underwater gliderHydrodynamicsAutonomous underwater gliders are buoyancy propelled vehicles. Their way of propulsion relies upon changing their buoyancy with internal pumping systems enabling them up and down motions, and their forward gliding motions are generated by hydrodynamic lift forces exerted on a pair of wings attached to a glider hull. In this study lift and drag characteristics of a glider were performed using Computational Fluid Dynamics (CFD) approach and results were compared with the literature. Flow behavior, lift and drag forces distribution at different angles of attack were studied for Reynolds numbers varying around 105 for NACA0012 wing configurations. The variable of the glider was the angle of attack, the velocity was constant. Flow velocity was 0.5 m/s and angle of the body varying from −8° to 8° in steps of 2°. Results from the CFD constituted the basis for the calculation the equations of motions of glider in the vertical plane. Therefore, vehicle motion simulation was achieved through numeric integration of
the equations of motion. The equations of motions will be solved in the MatLab software. This work will contribute to dynamic modelling and three-dimensional motion simulation of a torpedo shaped underwater glider.
AUV,
CFD,
drag,
glider,
underwater glider.
2019425732-4510.2478/TAR-2019-0021Transactions on Aerospace Research
Wojciech ZdrojewskiMeasuring Stand Tests of a Michell-Banki Water Turbine Prototype,Performed under Natural ConditionsHydrodynamicsThe article presents the result of tests of a single segment of a prototype water turbine, performed in order to determine its shaft power output as a function of rpm, and to verify the declared performance. The results have been compared with the outcomes of numerical calculations performed, for the same conditions, with the use of FLUENT software. The work presents information of crucial importance for presenting the process of testing the piece in question, such as: test environment, properties of the test piece, testing equipment used, as well as the methodology and the course of hydromechanical measurements, along with the characteristics of the results obtained. Then, the measurement results are discussed and analyzed. Conclusions are presented as well. Analysis of the results, taking into consideration the physical image of phenomena occurring in the case of flow-devices, such as water turbines, has made it possible to define other, important characteristics of the turbine, such as: output, shaft torque and efficiency, as a function of rpm and head of turbine. Test results have confirmed the expected mechanical and power-related properties of the turbine and have proved the numerical flow modeling model used effective. turbine geometry
hydromechanical measurements
water head
shaft power output
flow rate
turbine efficiency
2018225177-9510.2478/TAR-2018-0017Transactions on Aerospace Research
Bartosz Brzozowski, Karol Kawka, Krzysztof Kaźmierczak, Zdzisław Rochala, Konrad WojtowiczSupporting the Process of Aircraft Maintenance with Mobile DevicesMaintenanceMaintenance of aircraft is a complex process and therefore, in order to optimize the process, integrated information systems are increasingly used. Rapid development and wide availability of mobile devices equipped with powerful processors and with a wide range of modern communication connections suggests their high usability for enterprise IT systems. In the Department of Avionics and Air Armament of the Military University of Technology (WAT) an ERP-class (Enterprise Resource Planning) system, intended to support aircraft maintenance [4] has been designed and developed. The main concept of the system is to store the aircraft related and maintenance information in a central repository, i.e. in databases hosted on a central database server. This solution ensures concurrent availability of the data to a large group of authorized users. The key components of the system include the database server and client applications, which ensure access to centralized information resources, according to assigned user rights. The project involves development of client applications using three technologies: web, desktop and mobile one. Developed client applications have successfully passed integration tests perfomed using sample maintenance data. Currently works on user authorization security and wireless data security are under way. maintenance system
mobile application
aircraft
201722477-1810.2478/TAR-2017-0011Transactions on Aerospace Research
Jerzy Kozak, Tomasz Zakrzewski, Marta Witt, Martyna Dębowska-WąsakSelected problems of additive manufacturing using SLS/SLM processes.ManufacturingAdditive Manufacturing (AM) based on Selective Laser Sintering (SLS) and Selective Laser Melting (SLM) is relatively widely used to manufacture complex shape parts made from metallic alloys, ceramic and polymers. Although the SLM process has many advantages over the conventional machining, main disadvantages are the relatively poor surface quality and the occurrence of the material structure defect porosity.

The paper presents key problems directly related to the implementation of AM, and in particular the selection and optimization of process conditions. The first section examines the issues of dimensional accuracy, the second surface quality and porosity problem determining the mechanical properties of manufactured products.
additive manufacturing
metal 3D printing
SLS/SLM processes
2021126224-4410.2478/TAR-2021-0003Transactions on Aerospace Research
Maciej KarnyON THE AREOSPACE-GRADE ADHESIVES SHEAR STRENGTH TESTING WITH ASTM D5656 TEST AS AN EXAMPLEManufacturingThis article presents adhesive shearing test methods, focusing especially on the ASTM D5656 method. These methods will be briefly characterized and compared. The most important concerns about the D5656 method are described. With the use of ASTM D1002 and D5656 methods, the influence of adherend surface preparation on shearing properties of the bond is evaluated. Compared to sandblasting only, sandblasting followed by the FPL process (sulfochromate etching of aluminum) increased shear strength of joints by 35 % for ASTM D1002 tests and by 48% for D5656 tests. Comparing these two methods, shear strength obtained in D5656 tests is about two times higher than in D1002 tests. The cause for this phenomena is much larger adherend thickness in the D5656 method, which provides the coupons with increased stiffness. Shear modulus, calculated with 3 different calculation methods, showed differences in obtained results, which points to necessary actualization of D5656 standard. adhesives
shear modulus
ASTM D5656
shear strength
2019225533-4310.2478/TAR-2019-0008Transactions on Aerospace Research
Robert JaśkiewiczComparison of composite laminates machining methods and its influence on process temperature and edge qualityManufacturingThe article presents the description of technological trials and the results of three methods of machining carbon fiber reinforced composites panels. It also reviews the literature concerned heat affected zone in composites and its influence on material properties. As a part of the research, the cutting method using diamond coated saw was tested, as well as the milling method with two different types of carbide milling cutters. The processing of the panels was done using 4-axis CNC machine with special adapter for cutting discs in Composite Testing Laboratory (Center for Composite Technologies, Warsaw Institute of Aviation). The methods were compared in terms of machined edge quality and panel temperature during the processes. For this purpose, thermocouples were mounted into panels. Records from thermocouples were included. Edge quality and surface roughness have been checked by microscopic observation. Additionally, samples machined by each evaluated processing method were tested using differential scanning calorimetry (DSC). The method was used to determine the glass transition temperature of
the tested material. The article conclusions contain a comparison of three processing methods in terms of cutting quality, process temperature, processing method productivity as well as DSC tests results.
CFRP machining,
composite machining temperature,
DSC tests,
temperature tests.
2019425746-5410.2478/TAR-2019-0022Transactions on Aerospace Research
Przemysław DobrzańskiBonding of High Temperature Thermoplastic Carbon Composites with Resistance Welding TechniqueManufacturingThe article presents ‘state-of-the art’ on joining fibre reinforced thermoplastic composites with the use of resistance welding technique. Their welding process and potential difficulties connected with the process and quality control of a manufactured element are presented. The structure of a typical thermoplastic composite welding stand was also presented. The main welding technology elements were characterized: structure of the resistance element, implementation of the thermal process and pressure application required for joining materials. The paper also presents the required calibration ranges for a technological process with the use of strength test types SLS, DCB, SBS and nondestructive testing of joint with the ultrasonic method. thermoplastic composites
resistance welding
joining thermoplastic composites
201832521-1310.2478/TAR-2018-0018Transactions on Aerospace Research
Przemysław Dobrzański, Witold OleksiakDesign and analysis methods for composite bonded jointsManufacturingA literature review on existing design and analysis methods for composite adhesively bonded joints has been conducted. Methods that might form a basis for development of practical engineering methodology for adhesively bonded joints were selected and described. Starting from the simplest and the fastest analytical methods (closed-form solutions): average shear stress, shear lag model and adhesive beam model through more complex and more time consuming numerical methods supported by finite element analysis: global models, local models, cohesive zone models. Assumptions and applicability of each method was discussed. Simple and fast methods in order to be reliable have to include many conservative assumptions and therefore may lead to over-designed structure (weight penalty). Structural optimization and weight reduction require the usage of more complex and time consuming methods. Therefore, selection of adequate methods should always be balanced against strength, durability, costs and weight. composites
adhesives
analytical models
numerical models
stress analysis
2021126245-6310.2478/TAR-2021-0004Transactions on Aerospace Research
Przemysław Dobrzański, Witold OleksiakDesign and analysis methods for composite bonded jointsMaterialsA literature review on existing design and analysis methods for composite adhesively bonded joints has been conducted. Methods that might form a basis for development of practical engineering methodology for adhesively bonded joints were selected and described. Starting from the simplest and the fastest analytical methods (closed-form solutions): average shear stress, shear lag model and adhesive beam model through more complex and more time consuming numerical methods supported by finite element analysis: global models, local models, cohesive zone models. Assumptions and applicability of each method was discussed. Simple and fast methods in order to be reliable have to include many conservative assumptions and therefore may lead to over-designed structure (weight penalty). Structural optimization and weight reduction require the usage of more complex and time consuming methods. Therefore, selection of adequate methods should always be balanced against strength, durability, costs and weight. composites
adhesives
analytical models
numerical models
stress analysis
2021126245-6310.2478/TAR-2021-0004Transactions on Aerospace Research
Józef Krysztofik, Grzegorz SochaTest of damage to Inconel 718 alloy used in aviationMaterialsInconel 718 alloy was tested. A new type of specimens of variable cross-sectional area measuring part was used for the tests. This provided a continuous distribution of plastic strain in that part of the sample. The proposed method enables to replace a series of specimens by one specimen. The degradation of the material was obtained by static tensile test and the creep test. The permanent deformation that varies along the specimen axis allows for an analysis of damage induced by a plastic deformation. The degradation of the alloy corresponds with the changes of acoustics properties of the material - attenuation of ultrasonic waves. It allows to detennine the degree of damage to the material using a non-invasive - ultrasonic method. Using the damage parameter proposed by Johnson allows to obtain correlation between the non-destructive results and a damage degree of the material. The presented testing method delivers information about changes in the material structure caused by permanent deformation. material degradation
ultrasonic wave attenuation factor
damage parameter
non-destructive testing
20171246104-11610.2478/TAR-2017-0010Transactions on Aerospace Research
Wiesław KrzymieńMechanical properties of the package of ferromagnetic sheetsMaterialsThe paper presents the measurement method and results as well as the results of comparative calculations aimed at determination of material data for the package of ferromagnetic sheets insulated with epoxy lacquer. During the test, the package of sheets was treated as a 3D orthotropic material. The values of Young’s and Kirchhoff’s moduli for a pre-compressed package of sheets, in accordance with the used manufacturing technology of the medium and high power electric motors’ rotors, were detennined. The carried out FEM comparative calculations confirmed that the determined mechanical parameters of the package of sheets as a 3D orthotropic material, i.e. Young’s and Kirchhoff’s moduli, for the compressive stress range of 1.0÷2.5 MPa, are included in the linear range. It was assumed that the determined mechanical properties of the package of sheets are necessary at the design stage for FEM simulation calculations of the electric motors’ vibration and strength properties. As a result of the tests, it was found that they should be repeated in order to determine the properties of other sheets or those coated with different insulating lacquer. asynchronous motor
package of sheets
FEM
vibration
2017124654-6210.2478/TAR-2017-0006Transactions on Aerospace Research
Miłosz KalinowskiAero-Structural Optimization of Joined-Wing AircraftMultidisciplinary optimisationJoined-wing aircraft due to its energy characteristics is a suitable configuration for electric aircraft when designed properly. However, because of the specific for this aircraft phenomenons (e.g. static indeterminacy of structure, aerodynamic interference of lifting surfaces) it demands more complicated methods to model its behavior than a traditional aircraft configurations. For these reasons the aero-structural optimization process is proposed for joined-wing aircrafts that is suitable for preliminary design. The process is a global search, modular algorithm based on automatic geometry generator, FEM solver and aerodynamic panel method. The range of aircraft was assumed as an objective function. The algorithm was successfully tested on UAV aircraft. The improvement of 19% of total aircraft range is achieved in comparison to baseline aircraft. Time of evaluation of this global search algorithm is similar to the time characteristic for local optimization methods. It allows to reduce the time and costs of preliminary design of joined-wing. Joined-wing
multidyscyplinary optimization
preliminary design
2017424948-6310.2478/TAR-2017-0028Transactions on Aerospace Research
Marco Fioriti, Luca Boggero, Sabrina CorpinoPreliminary Sub-Systems Design Integrated in a Multidisciplinary Design Optimization FrameworkMultidisciplinary optimisationThe aircraft design is a complex subject since several and completely different design disciplines are involved in the project. Many efforts are made to harmonize and optimize the design trying to combine all disciplines together at the same level of detail. Within the ongoing AGILE (Horizon 2020) research, an aircraft MDO (Multidisciplinary Design Optimization) process is setting up connecting several design tools and competences together. Each tool covers a different design discipline such as aerodynamics, structure, propulsion and systems. This paper focuses on the integration of the sub-system design discipline with the others in order to obtain a complete and optimized aircraft preliminary design. All design parameters used to integrate the sub-system branch with the others are discussed as for their redefinition within the different detail level of the design. Multidisciplinary Design Optimization
Aircraft Sub-system Design
Design Space Parameters
201742499-2310.2478/TAR-2017-0025Transactions on Aerospace Research
Andrzej Felner, Robert KonieczkaDivagations on the appropriate satellite system from GNSS for aviation.NavigationAmerican military satellite GPS system is an element of the global GNSS. It emits two codes: the precise and civil one. As late as in 2000, intentional interference that decreased precision of localization was introduced, allowing navigation accuracy of 20 m. GPS was made available to civil users, however, at their own responsibility. So, if we use GPS for our own goals, we must consider the errors that occur and their consequences. Nonetheless, commercial and operational needs determine the necessity of permanent access to satellite signal with appropriate consistency, accessibility, reliability and precision. Hence, natural and intentional errors are compensated for, using appropriate methods, based on a given activity. GPS
reliability
precision
consistency
availability
GNNS
2021126275-9210.2478/TAR-2021-0006Transactions on Aerospace Research
Goncharenko Andriy ViktorovichThe User-Preferred Optimal Flight Parameters in an Active Navigational System in a Multi-Alternative SituationNavigationThe goal of this paper is to investigate the influence of the objectively existing effectiveness functions of an aircraft control system upon the control and managerial decision making process in the framework of the subjective entropy maximum princi-ple. The subjective analysis theory entropy paradigm makes it possible to consider the aircraft control system based upon personal preferences as an active system governed by an individual (active element of the control system) with the help of her/his individual subjective preferences optimal distributions obtained in conditions of operational multi-alternativeness and those operational alternatives the active system active element’s individual subjective preferences uncertainty. The described ap-proach takes into account the simple two-alternative operational situation in regards with the objectively existing effectiveness functions, related to the aircraft control system, in the view of a controlled parameter and a combination of it with its rate as the ratio. The obtained expressions for the objective functional extremal functions of the effectiveness and preferences, as well as the subjective entropy of the alternatives preferences, illustrated in diagrams visualize the situation and allow taking a good choice. The ideas of the required proper governing, managing, and control methods choice optimization with respect to only 2 alternative objective effectiveness functions arguments might be simple; nevertheless, increasing the number of parameters and further complication of the problem setting will not change the principle of the problem solution.control,
navigation,
decision making,
preferences,
entropy theory.
202022591-1210.2478/TAR-2020-0006Transactions on Aerospace Research
Stanisław Popowski, Witold DąbrowskiIndividual Autonomous Navigation SystemNavigationThe article presents the Individual Autonomous System Navigation (IANS) supporting–rescuer or firemen in terms of navigation. Basic assumptions, which such a system has to fulfill in terms of functionality and accuracy, are presented. The concept of the ISAN system is based on the implementation of inertial navigation system which the only one to permit fully autonomous functioning. Measurement sensors of the navigation system with microprocessor board are placed in the rescuer’s shoe. To limit the escalation of the navigation errors value, which in the case of inertial navigation rises exponentially, a procedure of navigation parameters upgrading at every step of the rescuer is introduced to the proposed system. This procedure guarantees the required accuracy of navigation achievement. The article describes a developed and manufactured demonstrator of the technology and presents main results of its research. The research conducted in a building consisted in walking on the same level several hundred meters in less than 10 minutes. A walking test with a change of walking height was also performed in order to estimate the accuracy of the vertical channel. Results of the demonstrator’s tests let us conclude that the error of navigation is below 1% of the travelled distance and the accuracy is linear in respect to time. The achieved accuracy is fully sufficient for a practical IANS application. rescuer navigation system
inertial navigation system
ZUPT procedure
Individual Autonomous Navigation System
IANS
2017324884-10610.2478/TAR-2017-0023Transactions on Aerospace Research
Mycola Chernyak, Vadym KolesnykThe accuracy of the navigational accelerometer with a nonlinear metrological model in operating conditions.NavigationA mathematical model of the error of the navigational accelerometer caused by the nonlinearity
of its metrological model, taking into account the influence of vibration, was developed. The method of experimental estimation of the vibration error based on the developed model was proposed. The main idea of the method is to evaluate parameters of the developed model during static tests in the terrestrial gravitational field and to calculate error according to the specific vibration characteristics – the amplitude in the case of harmonic vibration profile or the frequency band and the power spectral density in the case of random vibration. The effectiveness of the proposed method has been tested using three types of navigation accelerometers in comparison with the results of classical dynamic testing in various vibration conditions (harmonic, white noise, etc.).
navigational accelerometer,
vibration error,
metrological model,
conversion function,
identification of coefficients,
static test.
202032601-1010.2478/TAR-2020-0012Transactions on Aerospace Research
Michał Gęca, Konrad Pietrykowski, Karol RosińskiThe Research of Acoustic Emission of a Low-Power Aircraft EngineNoiseThis paper presents the methodology and investigation of the sound power level produced by a radial piston aircraft engine operating at varied speeds. The research model aircraft engine of a maximum power of 5.5 kW with a two-bladed airscrew was placed on a test bend. Its sound power level was calculated from the sound pressure level measured at 9 measurement points distributed on a hemispherical surface in a confined space in line with PN-EN 3744. Mean sound power generated by the ASP FS400AR engine is 96 dB at idle (2,880 rpm) and 105 dB at a cruising speed (4,740 rpm). Accordingly, it can be concluded that a sound level meter registered a higher sound power level at the points in front of the model aircraft engine than at the points behind it, whereas the lowest sound power level was registered directly above the engine. model aircraft engine
aerospace propulsion systems
sound power
noise
2018325214-2510.2478/TAR-2018-0019Transactions on Aerospace Research
Sławomir Cieślak, Wiesław Krzymień, Krzysztof SzafranAcoustic Characteristics of the Cabin of the Research Platform on the Airbag IL-PRC-600MNoiseHovercrafts are a universal means of transport intended for use on flat surfaces such as water, ice, snow, swamp, or sand. They are used in rescue operations and patrolling difficult areas inaccessible to other means of transport. The Institute of Aviation conducted acoustic measurements inside the cabin of the hovercraft to determine the source of the noise and the sound pressure exerted on the pilot and passengers. Assessment of the sources of noise in the cabin is made using the acoustic beamforming method. Assessment of the level of noise to which a pilot is exposed during the operation was prepared on the basis of a standard specifying the requirements and methods of determining occupational noise exposure [1]. noise
acoustics
acoustic
beamforming
hovercraft
cabin
2018225116-2310.2478/TAR-2018-0012Transactions on Aerospace Research
Sławomir Cieślak, Wiesław KrzymieńDrivetrain Noise of the Gyroplane I-28NoiseGyroplanes, as ultralight aircraft, are popular transport vehicles recently. Ultralight aircraft flights take place at a low altitude – their noise is not without effect on people and nature. The localization of the sources of noise and a possibility to decrease the noise of an gyroplane are described in this paper. The rules of design and exploitation of gyroplanes do not define the limits of emitted noise. gyroplane
noise
acoustic camera
beamforming
propeller noise
201812507-1610.2478/TAR-2018-0001Transactions on Aerospace Research
Georges Bridel, Zdobyslaw Goraj, Lukasz Kiszkowiak, Jean-Georges Brévot, Jean-Pierre Devaux, Cezary SzczepanskiJANUS – A New approach to air combat pilot trainingPILOTS TRAININGAdvanced jet training still relies on old concepts and solutions that are no longer efficient when considering the current and forthcoming changes in air combat. The cost of those old solutions to develop and maintain combat pilot skills are important, adding even more constraints to the training limitations. The requirement of having a trainer aircraft able to perform also light combat aircraft operational mission is adding unnecessary complexity and cost without any real operational advantages to air combat mission training.
Thanks to emerging technologies, the JANUS project will study the feasibility of a brand-new concept of agile manoeuvrable training aircraft and an integrated training system, able to provide a live, virtual and constructive environment. The JANUS concept is based on a lightweight, low-cost, high energy aircraft associated to a ground based Integrated Training System providing simulated and emulated signals, simulated and real opponents, combined with real-time feedback on pilot’s physiological characteristics: traditionally embedded sensors are replaced with emulated signals, simulated opponents are proposed to the pilot, enabling out of sight engagement. JANUS is also providing new cost effective and more realistic solutions for “Red air aircraft” missions, organised in so-called “Aggressor Squadrons”.
air combat;
advanced training;
red air;
training concept;
innovation;
201942577-2210.2478/TAR-2019-0019Transactions on Aerospace Research
Tae-Hyeong Yi, Jing Lou, Cary Kenny Turangan, Piotr WolanskiNumerical study of detonation processes in rotating detonation engine and its propulsive performance.PROPULSIONNumerical studies on detonation wave propagation in rotating detonation engine and its propulsive performance with one- and multi-step chemistries of a hydrogen-based mixture are presented.
The computational codes were developed based on the three-dimensional Euler equations coupled with source terms that incorporate high-temperature chemical reactions. The governing equations were discretized using Roe scheme-based finite volume method for spatial terms and second-order Runge-Kutta method for temporal terms. One-dimensional detonation simulations with one- and multi-step chemistries of a hydrogen-air mixture were performed to verify the computational codes and chemical mechanisms. In two-dimensional simulations, detonation waves rotating in a rectangular chamber were investigated to understand its flowfield characteristics, where the detailed flowfield structure observed
in the experiments was successfully captured. Three-dimensional simulations of two-waved rotating detonation engine with an annular chamber were performed to evaluate its propulsive performance in
the form of thrust and specific impulse. It was shown that rotating detonation engine produced constant thrust after the flowfield in the chamber was stabilized, which is a major difference from pulse detonation engine that generates repetitive and intermittent thrust.
detonation wave,
rotating detonation engine,
propulsion,
chemical kinetics,
finite volume method,
adaptive mesh refinement.
2020326030-4810.2478/TAR-2020-0015Transactions on Aerospace Research
Michal Folusiak, Karol Swiderski, Piotr WolanskiNumerical modeling of RDE.PROPULSIONThe idea of using the phenomenon of rotating detonation to propulsion has its roots in fifties of
the last century in works of Adamson et al. and Nicholls et al. at the University of Michigan. The idea was recently reinvented and experimental research and numerical simulations on the Rotating Detonation Engine (RDE) are carried in numerous institutions worldwide, in Poland at Warsaw University
of Technology (WUT) since 2004. Over the period 2010-2014 WUT and Institute of Aviation (IOA) jointly implemented the project under the Innovative Economy Operational Programme entitled ‘Turbine engine with detonation combustion chamber’. The goal of the project was to replace
the combustion chamber of turboshaft engine GTD-350 with the annular detonation chamber.
This paper is focused on investigation of the influence of a geometry and flow conditions on
the structure and propagation stability of the rotating detonation wave. Presented results are in majority an outcome of the aforementioned programme, in particular authors’ works on the development of
the in-house code REFLOPS USG and its application to simulation of the rotating detonation propagation in the RDE.
RDE,
CFD,
modeling,
detonation,
numerical
2020426113-4710.2478/TAR-2020-0019Transactions on Aerospace Research
Anatoly A. Vasil`evRotating detonation: History, results, problems.PROPULSIONAmong of modern papers devoted to numerical modeling of rotated waves the greater part of papers are based on assumption that such wave propagates with velocity equals to the Chapman-Jouguet velocity of ideal detonation model with plane front. But the experimental velocities of rotated detonation waves, as a rule, are less (and even much less) the velocity of ideal Chapman-Jouguet detonation. Such regimes are named as low-velocity detonation or quasi-detonation and its characteristics are practically not investigated carefully. Moreover, similar to the spinning detonation, the strong connection of velocity of rotated transverse waves with the acoustic waves of reaction products was observed. So the new model with an allowance for the losses of impulse and energy must be used at numerical modeling of RDE and new experimental investigations of regimes with understated velocity must be carried out. In given paper some important aspects of rotated detonation waves and new experimental results are analyzed:
the multifront system of rotated waves; correlation of rotation velocity of waves with acoustic characteristics of reaction products; streak-records trajectory of rotated waves on moving film; pressure and temperature profiles of rotating waves; velocity deficit and energy-release.
spinning detonation,
rotated detonation wave,
self-sustained supersonic regimes and their nature,
low-velocity detonation,
“quasi-detonation”,
energy-release in reactive mixtures,
instability of reaction zone,
connection of DW instabilities with acoustic vibrations of reaction products,
looses of impulse and energy.
2020426148-6010.2478/TAR-2020-0020Transactions on Aerospace Research
Sergiy YepifanovAircraft turbine engine automatic control based on adaptive dynamic models.PROPULSIONOne of the most perspective development directions of the aircraft engine is the application of adaptive digital automatic control systems (ACS). The significant element of the adaptation is
the correction of mathematical models of both engine and its executive, measuring devices. These models help to solve tasks of control and are a combination of static models and dynamic models, as static models describe relations between parameters at steady-state modes, and dynamic ones characterize deviations of the parameters from static values.
The work considers problems of the models’ correction using parametric identification methods.
It is shown that the main problem of the precise engine simulation is the correction of the static model. A robust procedure that is based on a wide application of a priori information about performances of
the engine and its measuring system is proposed for this purpose. One of many variants of this procedure provides an application of the non-linear thermodynamic model of the working process and estimation of individual corrections to the engine components’ characteristics with further substitution of
the thermodynamic model by approximating on-board static model. Physically grounded estimates are obtained based on a priori information setting about the estimated parameters and engine performances, using fuzzy sets.
Executive devices (actuators) and the most inertial temperature sensors require correction to their dynamic models. Researches showed, in case that the data for identification are collected during regular operation of ACS, the estimates of dynamic model parameters can be strongly correlated that reasons inadmissible errors.
The reason is inside the substantial limitations on transients’ intensity that contain regular algorithms of acceleration/deceleration control. Therefore, test actions on the engine are required. Their character and minimum composition are determined using the derived relations between errors in model coefficients, measurement process, and control action parameters.
turbine engine,
automatic control,
model,
adaptation
2020426161-7010.2478/TAR-2020-0021Transactions on Aerospace Research
Qiaofeng Xie, Zifei Ji, Haocheng Wen, Zhaoxin Ren, Piotr Wolanski, Bing WangReview on the rotating detonation engine and its typical problems.PROPULSIONDetonation is a promising combustion mode to improve engine performance, increase combustion efficiency, reduce emissions, and enhance thermal cycle efficiency. Over the last decade, significant progress has been made towards the applications of detonation mode in engines, such as standing detonation engine (SDE), Pulse detonation engine (PDE) and rotating detonation engine (RDE), and the understanding of the fundamental chemistry and physics processes in detonation engines via experimental and numerical studies. This article is to provide a comprehensive overview of the progress in the knowledge of rotating detonation engine from the different countries. New observations of injection, ignition, and geometry of combustor, pressure feedback, and combustion modes of RDE have been reported. These findings and advances have provided new opportunities in the development of rotating detonation for practical applications. Finally, we point out the current gaps in knowledge to indicate which areas future research should be directed at.
Detonation,
propulsion system,
rotating detonation.
20204261107-16310.2478/TAR-2020-0024Transactions on Aerospace Research
Grzegorz KunikowskiElectricity Storage in Energy ClustersPropulsionThe article aims to present the results of analysis and evaluation of using energy clusters as a bulk electricity storage. There were developed an analytical model of a sample microgrid (on-grid) and analysed using a software dedicated for optimizing such microgrids. The model of microgrid consist on electricity commercial and residential loads, photovoltaic and wind installations and batteries. energy clusters
electricity storage
microgrid
2018425325-3710.2478/TAR-2018-0027Transactions on Aerospace Research
Paweł Magryta, Konrad Pietrykowski, Michał GęcaThermodynamic Model of the ASz-62IR Radial Aircraft EnginePropulsionThe article presents assumptions of the one-dimensional model of the ASz-62IR aircraft engine. This model was developed in the AVL BOOST software. The ASz-62IR is a nine cylinder, aircraft engine in a radial configuration. It is produced by the Polish company WSK “PZL-Kalisz” S. A. The model is used for calculating parameters of the fuel stream and the air stream in intake system of the engine, as well as for the analyses of the combustion process and the exhaust flow to the external environment. The model is based on the equations describing the isentropic flow. The geometry of the channels and all parts of the model has been mapped on the basis of empirical measurements of the engine elements. The model assumes indirect injection where the gasoline was used as a fuel with the calorific value of 43.5 MJ/kg. The model assumes a mixture of a stoichiometric ratio of 14.5. This model is only part of the overall the ASz-62IR engine model. After the simulation tests on the full model the obtained results confirmed the correctness of the model used to create the mixture. It was found that the AVL BOOST software is good for the implementation of this type of work. aviation propulsion
AVL BOOST
engine model
charge exchange
mixture formation
2018125036-4810.2478/TAR-2018-0004Transactions on Aerospace Research
Jan KindrackiTemperature Measurements in the Detonation Chamber Supplied by Air from Centrifugal Compressor and Gaseous HydrogenPropulsionIn this paper, the experimental results of a detonation chamber fed by air from a centrifugal compressor are presented. The detonation chamber was equipped with many different sensors, mostly thermocouples, which were placed in 11 different positions. The distribution of temperature changes along the chamber and radial temperature profile at the outlet are provided. The results here confirm the existence of high mixture stratification. Such mixture stratifications and temperature profiles may be used as an additional chamber wall cooling method. The experiments performed, address key issues regarding the chamber choking problem caused by turbines. The relationship between the turbine performance and detonation chamber are crucial for proper control of turbine jet engine. rotating detonation
RDE engine
temperature measurements
201732487-2310.2478/TAR-2017-0019Transactions on Aerospace Research
Anna M. Mazur, Tomasz Korniluk, Roman DomańskiMeasuring and Testing the Parameters of a Battery Pack Designed for Powering Unmanned Aircraft Systems at Various TemperaturesPropulsionThis paper describes results of tests dedicated to studying – in simulated environmental conditions – operation of a battery pack designed for powering unmanned aircraft systems. In particular, the tests concerned determining the electrical parameters of battery packs, with and without radiators, during their operation in changing environmental conditions and resistance to large temperature fluctuations. Amicell, a high density lithium polymer battery manufactured by the Israeli Amit Industries ltd., was selected for testing. The test results present characteristics of the batteries tested in different temperatures and allow for designing and trying out proper battery protections against environmental conditions, with the intention to attain continuous and correct operation. The tests have been carried out in the accredited Environmental Test Laboratory which is part of the Department of Avionics of the Institute of Aviation in Poland. lithium polymer batteries
environmental test laboratory
UAS
Unmanned Aircraft Systems
2017324846-6210.2478/TAR-2017-0021Transactions on Aerospace Research
Ruben Di Batista, Maria Teresa Scelzo, Maria Rosaria VetranoNUMERICAL STUDY OF AN ISOTHERMAL SLUSH FLOW FOR AEROSPACE PROPULSION APPLICATIONSPROPULSIONSlushes are two-phase solid-liquid single-species cryogenic fluids that exhibit an increased density and a greater heat capacity with respect to the corresponding normal boiling point liquids. These promising features are of large interest for applications that exploit slush as a thermal fluid, like super magnets refrigeration, cryogenic cooling of bio-materials or air conditioning, and for aerospace systems that use slush fluids as fuel or oxidizer. Several programs in the frame of the research on Slush Hydrogen (SLH2) as a new-generation fuel for aerospace propulsion have been started in the past. This work was carried out in the framework of a VKI research activity promoted by the Predict ESA Technology Research Programme, to investigate experimentally and numerically the behavior of slush flows in a representative upper stage feeding line. In this paper, we present a simulation based on a granular two-fluid model on an isothermal solid liquid mixture (slurry) and a Nitrogen slush (SLN2) fluid flowing in a horizontal pipe. A finite-volumes discretization using the software library OpenFOAM was benchmarked against experimental and numerical literature data, to assess the accuracy of the code in predicting pressure drops along the pipe axis and solid particle distribution across the pipe diameter. Moreover, the effects of concentration and inlet velocity are investigated. We show that the numerical model fairly reproduces the literature data in terms of important aspects as the solid volume fraction distribution and the pressure drops, especially for high flow rates. fluid dynamics
space propulsion
multiphase flows
CFD
cryogenics
slush flows
2019225582-9510.2478/TAR-2019-0011Transactions on Aerospace Research
Marek Idzikowski, Wojciech MiksaGround and In-Fligh Testing of Cooling Efficiency of Turboprop Engine CompartmentPropulsionThis article presents selected results of I-31T propulsion tests, obtained in the framework of EU project ESPOSA (Efficient Systems and Propulsion for Small Aircraft). I-31T aircraft, as a testbed, was fitted with 180 kW turboprop engine TP100. The scope of the work include results of ground and in-flight tests of engine compartment cooling suitability. The purpose of the cooling tests was to prove that temperatures of the propulsion components are within limits set by the engine manufacturer for the engine type in the most disadvantageous conditions on the ground and in flight up to aircraft maximum altitude, maximum ambient temperature and after standard engine shutdown. Engine oil cooling is beyond the scope of this work. light aircraft
in-flight tests
turboprop engine installation
turboprop engine integration in airframe
engine compartment cooling
2018125017-2510.2478/TAR-2018-0002Transactions on Aerospace Research
Marek Idzikowski, Wojciech MiksaFlight tests of turboprop engine with reverse air intake systemPropulsionThis work presents selected results of I-31T propulsion flight tests, obtained in the framework of ESPOSA (Efficient Systems and Propulsion for Small Aircraft) project. I-31T test platform was equipped with TP100, a 180 kW turboprop engine. Engine installation design include reverse flow inlet and separator, controlled from the cockpit, that limited ingestion of solid particulates during ground operations. The flight tests verified proper air feed to the engine with the separator turned on and off. The carried out investigation of the intake system excluded possibility of hazardous engine operation, such as compressor stall, surge or flameout and potential airflow disturbance causing damaging vibration of the engine body. Finally, we present evaluation of total power losses associated with engine integration with the airframe. light aircraft
flight tests
turboprop engine installation
turboprop engine integration
reverse air flow to engine
2018325226-3610.2478/TAR-2018-0020Transactions on Aerospace Research
Alfons Mayer, Wolter WielingGreen Propulsion Research at TNO the NetherlandsPropulsionThis paper describes the recent theoretical and experimental research by the Netherlands Organisation for Applied Scientific Research (TNO) into green replacements for hydrazine, hydrazine derivatives and nitrogen tetroxide, as propellants for in-space propulsion. The goal of the study was to identify propellants that are capable of outperforming the current propellants for space propulsion and are significantly less hazardous for humans and the environment. Two types of propellants were investigated, being monopropellants and bipropellants. The first section of the paper discusses the propellant selection. Nitromethane was found to be the most promising monopropellant. As bipropellant, a combination of hydrogen peroxide (HP) and ethanol was selected, where the ethanol is rendered hypergolic with hydrogen peroxide. The second part of the paper describes the experimental verification of these propellants by means of engine testing. Initiation of the decomposition of nitromethane was found to be problematic, hypergolic ignition of the hydrogen peroxide and ethanol bipropellant however was successfully demonstrated. Green propulsion
monopropellant
bipropellant
hydrogen peroxide
nitromethane
201842531-2410.2478/TAR-2018-0026Transactions on Aerospace Research
Lyubomyr Sabadosh, Serhii Larkov, Oleg Kravchenko, Vladyslav SeredaIncreasingly Safe, High-Energy Propulsion System for Nano-SatellitesPropulsionNumerous attempts have been undertaken to develop propulsion systems for nano-satellite-type spacecrafts to enable their maneuvering in orbits. One of the potentially viable chemical propellant propulsion systems is a hybrid system. The present paper studies propellant composition variants with the metal hydride as fuel that can be chosen for a nano-satellite hybrid propulsion system. It defines key requirements for chemical propellant nano-satellite propulsion systems, and specifies potential propellant pairs based on a compact metal hydride. The study describes basic technical characteristics of a 1U CubeSat propulsion system. satellite propulsion
metal hydride
hydrogen peroxide
2018425338-4410.2478/TAR-2018-0028Transactions on Aerospace Research
Mateusz Sochacki, Janusz NarkiewiczPropulsion System Modelling for Multi-Satellite Missions Performed by NanosatellitesPropulsionProgress in miniaturization of satellite components allows complex missions to be performed by small spacecraft. Growing interest in the small satellite sector has led to development of standards such as CubeSat, contributing to lower costs of satellite development and increasing their service competitiveness. Small satellites are seen now as a prospective replacement for conventional sized satellites in the future, providing also services for demanding users. New paradigms of multi-satellite missions such as fractionation and federalization also open up new prospects for applications of small platforms. propulsion
nanosatellite
formation flying
constellations
fractionated satellite
federated satellite systems
2018425358-6710.2478/TAR-2018-0030Transactions on Aerospace Research
Patryk Palej, Tomasz PalaczPreliminary design analysis of regenerative cooling for N2O/Alkohol small scale liquid rocket enginePropulsionThis paper presents a concept of a small scale liquid-propellant rocket engine designed in AGH Space Systems for sounding rocket. During preliminary design of thermal aspects various ways of cooling were evaluated and described. Possible issues and design approaches for ablative, radiation and regenerative cooling are raised. The authors describe available solutions. Regenerative cooling is especially concerned as it is most popular solution in bi-liquid engines, in which alcohol fuel acts as coolant and is preheated before it reaches combustion chamber. To estimate a possible temperature distribution - and thus an applicability of such a system in the engine - a mathematical model of heat transfer was developed. Unique element of said engine is its oxidizer - nitrous oxide, which have been rarely used to date. Comparison between typical LOX bi-liquids is given and major differences that affect cooling arrangement are discussed. The authors compared different combinations of coolants, fuel/oxidizer ratios etc. to optimize the temperature distribution which is a key factor for the engine performance. liquid rocket engine
regenerative cooling
nitrous oxide
sounding rocket
2018325287-10210.2478/TAR-2018-0024Transactions on Aerospace Research
Yevhen MartseniukSteady and transient thermal state of turbine disc estimation for life time monitoringPropulsionIn connection with increasing intensification of the working process in a gas turbine engine and increasing requirements for economy, the problem of defining and monitoring the main parts lifetime is becoming more vital. Modern algorithms of the monitoring systems are based on taking into account
the levels of part temperature and total equivalent stress throughout the flight cycle. Thermal and stress-strain states of the critical zones of the main parts are determined on the basis of information received from the sensors installed in the engine gas path. Turbine disks are located in the internal cavities of
the engine and are cooled by air from the compressor. However, in some designs, the disk cavity can be separated from the place of cooling air bleed by several stages of non-contact labyrinth seals, which will lead to some delay in changing the parameters of the cooling air flow when changing the engine operating mode. It has been observed that if this situation is not taken into account, it can lead to significant errors (more than 40%) in determining the lifetime for the peripheral zone of the disk. At the same time, this error is minimal for the hub and the middle zone of the disk, and the existing monitoring algorithms can be used.
lifetime,
monitoring,
thermal-stress state,
model.
2020326021-2910.2478/TAR-2020-0014Transactions on Aerospace Research
Patryk Palej, Tomasz PalaczPreliminary design analysis of regenerative cooling for N2O/Alkohol small scale liquid rocket engineRegenerative coolinfThis paper presents a concept of a small scale liquid-propellant rocket engine designed in AGH Space Systems for sounding rocket. During preliminary design of thermal aspects various ways of cooling were evaluated and described. Possible issues and design approaches for ablative, radiation and regenerative cooling are raised. The authors describe available solutions. Regenerative cooling is especially concerned as it is most popular solution in bi-liquid engines, in which alcohol fuel acts as coolant and is preheated before it reaches combustion chamber. To estimate a possible temperature distribution - and thus an applicability of such a system in the engine - a mathematical model of heat transfer was developed. Unique element of said engine is its oxidizer - nitrous oxide, which have been rarely used to date. Comparison between typical LOX bi-liquids is given and major differences that affect cooling arrangement are discussed. The authors compared different combinations of coolants, fuel/oxidizer ratios etc. to optimize the temperature distribution which is a key factor for the engine performance. liquid rocket engine
regenerative cooling
nitrous oxide
sounding rocket
2018325287-10210.2478/TAR-2018-0024Transactions on Aerospace Research
Goncharenko Andriy ViktorovichMulti-Optional Hybrid Functions Entropy Doctrine Advantages for a State Maximal Probability DeterminationRELIABILITYThe presented paper considers a comparison of the traditional methods for the state maximal probability determination to the proposed hybrid probabilistic and variational concept. It is shown
the advantages of the described multi-optional hybrid-effectiveness functions uncertainty measure conditional optimization doctrine in the sense of avoiding the traditional ways analytical complicatedness concerning the maximal probability of the possible state determination. The results of the numerical example are presented.
entropy,
dynamic state,
risk,
Markovian random process
2020125853-6510.2478/TAR-2020-0004Transactions on Aerospace Research
Goncharenko Andriy ViktorovichHYBRID-OPTIONAL EFFECTIVENESS FUNCTIONS ENTROPY CONDITIONAL EXTREMIZATION DOCTRINE CONTRIBUTIONS INTO ENGINEERING SYSTEMS RELIABILITY ASSESSMENTSRELIABILITYIn this publication a Doctrine for the Conditional Extremization of the Hybrid-Optional Effectiveness Functions Entropy is discussed as a tool for the Reliability Assessments of Engineering Systems. Traditionally, most of the problems having been dealt with in this area relate with the probabilistic problem settings. Regularly, the optimal solutions are obtained through the probability extremizations. It is shown a possibility of the optimal solutions “derivation”, with the help of a model implementing a variational principle which takes into account objectively existing parameters and components of the Markovian process. The presence of an extremum of the objective state probability is observed and determined on the basis of the proposed Doctrine with taking into account the measure of uncertainty of the hybrid-optional effectiveness functions in the view of their entropy. Such approach resembles the well known Jaynes’ Entropy Maximum Principle from theoretical statistical physics adopted in subjective analysis of active systems as the subjective entropy maximum principle postulating the subjective entropy conditional optimization. The developed herewith Doctrine implies objective characteristics of the process rather than subjective individual’s preferences or choices, as well as the states probabilities maximums are being found without solving a system of ordinary linear differential equations of the first order by Erlang corresponding to the graph of the process. Conducted numerical simulation for the proposed mathematical models is illustrated with the plotted diagrams. effectiveness functions entropy
hybrid-optional effectiveness
multi-optionality
optimal distribution
variational principle
probability
reliability
entropy maximum principle
optimal periodicity
2019225596-10610.2478/TAR-2019-0012Transactions on Aerospace Research
Joanna HessThe Life Cycle of a Training Project in a Research and Development UnitResearchers trainingThe article describes the life cycle of a training project in a research and development unit, from setting the training target, through analyzing the needs of the group, establishing workshops’ programs and logistics, up to the evaluation and implementation support. The role of human capital has been presented in the article, thus the need for training organization has been demonstrated to improve quality of work. The article also describes characteristics of the training market, defining types of projects addressed to representatives of the most often trained groups in the research and development unit, like professionals, managers and research workers. Methods and tools aiding the training system analysis and monitoring have also been introduced in the text with a goal to reflect customer, employer, and trainee satisfaction. A process of raising qualifications of employees was described at the Institute of Aviation. It has been found that internal trainings from the subject matter of “project management” are the best solution for research and development centers. training
project life cycle
research and development unit
2017124615-2610.2478/TAR-2017-0002Transactions on Aerospace Research
Adam Rosłowicz, Paweł BednarczykAnalysis of heat transfer in a supersonic rocket headROCKET TECHNOLOGYDesign of supersonic H1 rocket by the Rocketry Group of Students’ Space Association (SR SKA) requires an analysis of thermal phenomena occurring in the elements particularly exposed to the high temperature gas. This paper contains a description of the methodology and the results of numerical simulation of heat transfer in the elements of the rocket head. The starting points were the flight conditions (3 characteristic points defined by altitude and Mach number) and independently calculated adiabatic temperature field of the gas. ANSYS Fluent code was used to determine the temperature field on the surface of the rocket. Computed cases were viscous and inviscid flow (for comparison). Based on the results formulated for the viscous case heat transfer boundary conditions, the numerical model and the thermophysical properties of materials were defined. The model was limited to a brass top part of the head and a part of a composite dome. Analytical and empirical method of “intermediate enthalpy” determined distribution of the heat transfer coefficient on the rocket surface. Then the transient heat transfer was calculated with the ANSYS system. It included the range from the rocket launch, moment of maximum Mach number to sufficient structure cooling. The results of the analyses were conclusions relevant to the further development work. Excessive heating of composite structures during the flight has been shown. rocket technology
computational fluid mechanics
unsteady heat transfer
ANSYS software
2017124679-9410.2478/TAR-2017-0008Transactions on Aerospace Research
Izabela Korzec, Tomasz Łusiak, Martin BugajTests of selected mechanical properties of welded joints in rotorcraft.Rotorcraft DiagnosticsThe following article presents experimental use of different ways of inguinal connecting of aircraft elements using TIG (Tungsten Inert Gas), MAG (Metal Active Gas) and arched coated electrode. The object of the research were samples of rotorcraft elements, which were connected to each other by TIG, MAG methods and the coated electrode. The main aim of the research was to determine selected mechanical properties in particular hardness and strength of inguinal joints and then, based on the tests carried out, the best methods were selected. Welding
aerospace components
TIG
MAG
coated electrode
2021126264-7410.2478/TAR-2021-0005Transactions on Aerospace Research
Robert KonieczkaMi-2 Helicopters Used within the Structures of the Aviation Detachment of the Ministry of InteriorRotorcraft operationsIn the article, the author presents the wide-scale use of Mi-2 helicopters in the different entities subordinated to the Minister of Interior - from the introduction of the design, until the present. Insights are presented pertaining to the early stages of the helicopter’s service life within the structures of the 103rd NJW MSW Aviation Regiment in the 1960s. The article describes selected aspects related to the introduction of the design, training, operational use and problems encountered. The service life of Mi-2 helicopters operating within the structures of the Ministry of Interior ended upon liquidation of the Ministry’s Aviation Detachment. That is when another chapter in the history of the helicopters was started, this time operated within the structures of the Police and Border Guard forces, where their service life has not been fully used up until this day. The paper describes the reality of every-day use to perform specific tasks, presents the location of aerodromes, touches upon a shift in the philosophy behind the use of the helicopters, and describes their strong and weak points. The PZL-Kania helicopter has been also presented, being a modernized version of the Mi-2, and still used in Poland within the aviation forces of the Ministry of Interior and Administration. Ministry of Interior and Administration
Mi-2 helicopter
public safety
Nadwiślańskie Jednostki Wojskowe
Border Guard
Police
2018225134-5010.2478/TAR-2018-0014Transactions on Aerospace Research
Miłosz RusieckiMi-2 Helicopters Operating at SeaRotorcraft operationsThe article describes participation of Mi-2 helicopters in both military and civilian operations at sea. Although the multipurpose Mi-2 rotorcraft were not designed to operate in the harsh environment over the sea, they became - in the second half of the 1960s and in the 1970s - a standard type performing a wide array of tasks at sea. Modern turboshaft engines, a favorable weight-to-power ratio and a dual engine configuration were all factors enabling safe flight over the sea, at considerable distances from land. The specialized Mi-2RM variant designed by WSK PZL Świdnik provided the Naval Aviation with an opportunity to establish, in the 1st half of the 1970s, a unique marine air rescue system. The last Mi-2RM used for rescue missions was decommissioned as late as in 2010, although at that stage it was only used for aircrew training purposes. The Navy was also using the Mi-2Ch variant tasked with creating smokescreens to conceal vessels and port facilities. General purpose variants of the helicopter were used to transport people and goods. They also performed well during patrolling missions and while identifying various types of contamination. helicopters
sea operations
Mi-2 versions
military and civilian use of the Mi-2 helicopter
2018225160-7610.2478/TAR-2018-0016Transactions on Aerospace Research
Małgorzata Wojtas, Łukasz Czajkowski, Kazimierz SzumańskiGround test stands for testing rotors in insulated conditions.Rotorcraft technologyThe paper generally discusses Whirl Tower research stands. Whirl Tower stands are used to test, among others, rotorcrafts main rotors in hovering. The work presents an overview of similar solutions of test stand presented in the available literature and online data. Beyond these solutions the paper also contains test stands used so far at the Institute of Aviation, these solutions were prepared for testing one type of rotor (for example: only for gyroplane rotors).

The article provides information about new (Whirl Tower) test stand fully designed and manufactured in Łukasiewicz Research Network ‒ Institute of Aviation (Ł-ILOT). One of the basic assumptions is that it will be a universal test stand, giving the possibility to test different types of rotors.

Moreover, the article discusses the types of tests and research that can be carried out on this type of test stand, tests that are performed to ensure the safety of the rotor design.
main rotor
whirl tower
tests
2021126215-2310.2478/TAR-2021-0002Transactions on Aerospace Research
Jarosław StanisławskiPerformance of Quiet HelicopterROTORCRAFT TECHNOLOGYNoise generated by helicopters is one of the main problems associated with the operation of rotorcrafts. Requirements for reduction of helicopter noise were reflected in the regulations introducing lower limits of acceptable rotorcraft noise. A significant source of noise generated by helicopters are the main rotor and tail rotor blades. Radical noise reduction can be obtained by slowing down the blade tips speed of main and tail rotors. Reducing the rotational speed of the blades may decrease rotor thrust and diminish helicopter performance. The problem can be solved by attaching more blades to main rotor. The paper presents results of calculation regarding improvement of the helicopter performance which can be achieved for reduced rotor speed but with increased number of rotor blades. The calculations were performed for data of hypothetical light helicopter. Results of simulation include rotor loads and blade deformations in chosen flight conditions. Equations of motion of flexible rotor blades were solved using the Galerkin method which takes into account selected eigen modes of the blades. The simulation analyzes can help to determine the performance and loads of a quiet helicopter with reduced rotor speed within the operational envelope of helicopter flight states.helicopter,
noise,
rotor loads
202012581-1710.2478/TAR-2020-0001Transactions on Aerospace Research
Wiesław Krzymień, Michał Szmidt, Sławomir CieślakVibration properties of steel constructed hospital elevated helipads.ROTORCRAFT TECHNOLOGYPolish Medical Air Rescue helicopters facilitate the rapid transport of patients to large hospitals.
The requirements of the space around the helipad and the safety of flight operations mean that hospitals closer to city centers create more elevated helipads than ground-based helipads. The helipads can vary in the way they are constructed and located - depending on the possibilities offered by hospital buildings and their surroundings.
Vibroacoustics Laboratory of the Institute of Aviation measured the vibration properties of some elevated helipads. The goal of this research was to determine the vibration properties of the helipads itself and the transmission of vibrations to the construction of the helipads, the building and its equipment caused by the landing and taking-off of a helicopter.
This article presents some of the results of measurements of vibrations of steel constructed elevated helipads with the use of a modal hammer and while landing and taking-off of a helicopter, as well as comparison of the vibration properties concerning various elevated concrete helipads.
elevated helipads,
ground vibration tests,
vibration measurements
2020326011-2010.2478/TAR-2020-0013Transactions on Aerospace Research
Jarosław StanisławskiEffectiveness of the compound helicopter configuration in rotorcraft performance increase.ROTORCRAFT TECHNOLOGYThe article presents the results of calculations applied to compare flight envelopes of varying helicopter configurations. Performance of conventional helicopter with the main and tail rotors, in the case of compound helicopter, can be improved by applying wings and pusher propellers which generate an additional lift and horizontal thrust. The simplified model of a helicopter structure, consisting of a stiff fuselage and the main rotor treated as a stiff disk, is applied for evaluation of the rotorcraft performance and the required range of control system deflections. The more detailed model of deformable main rotor blades, applying the Galerkin method, is used to calculate rotor loads and blade deformations in defined flight states. The calculations of simulated flight states are performed considering data of a hypothetical medium class helicopter with the take-off mass of 6,000kg. In the case of both of the helicopter configurations, the articulated main rotor hub is taken under consideration. According to the Galerkin method, the elastic blade model allows to compute blade deformations as a combination of the blade bending and torsional eigen modes. Introduction of additional wing and pusher propellers allows to increase the range of operational speed over 300 km/h. Results of the simulation are presented as time-runs of rotor loads and blade deformations and in a form of disk distribution plots of rotor parameters. The simulation method can be useful in defining requirements for a high speed rotorcraft.compound helicopter,
rotor loads,
blade deformations
2020426181-10610.2478/TAR-2020-0023Transactions on Aerospace Research
Andrzej Felner, Robert KonieczkaROTORCRAFT IN THE PERFORMANCE BASED NAVIGATION INTERNATIONAL CIVIL AVIATION ORGANIZATION IMPLEMENTATIONROTORCRAFT TECHNOLOGYEuropean Commision adopted in July new regulations about laying down airspace usage requirements and operating procedures concerning performance based navigation. It is next step in realization of the the global program PBN ICAO. At the 36th General Assembly of ICAO held in 2007, the Republic of Poland agreed to ICAO resolution A36-23 which urges all States to implement PBN. In future aviation concepts the use of Performance Based Navigation (PBN) is considered to be a major Air Traffic Management (ATM) concept element. ICAO has drafted standards and implementation guidance for PBN in the ICAO Doc 9613 “PBN Manual”. The Based Performance Navigation Concept represents and shift from sensor-based to performance based navigation connected with criteria for navigation: accuracy, integrity, availability, continuity and functionality depending on the phase of the flight. Through PBN and changes in the communication, surveillance and ATM domain, many advanced navigation applications are possible to improve airspace efficiency, improve airport sustainability, reduce the environmental impact of air transport in terms of noise and emission, increase safety and improve flight efficiency. PBN
ATM
integrity
accuracy
continuity
availability
2019125453-6410.2478/TAR-2019-0005Transactions on Aerospace Research
Łukasz CzajkowskiMECHANICAL ANALYSIS PROCESS OF A COAXIAL COUNTER ROTOR FOR APPLICATIONS IN UNMANNED ULTRA-LIGHT UNITSRotorcraft technologyAs the rotor configuration has the most impact on helicopter properties, the process of determination the assumptions for rotor design is a very important factor in the early stage of rotorcraft development. The following paper presents a mechanical analysis process used at the Institute of Aviation to quickly develop a coaxial rotor prototype applicable in ultra-light unmanned helicopter which has the potential for further improvement of its flight parameters. The article describes the rotor analysis process due to its feasibility based on commercially available solutions, the process of formulating assumptions for the entire structure, MES analysis of the rotor parts all leading to creation of the rotor prototype. rotor analysis
coaxial rotor
ultra-light
2019225544-6410.2478/TAR-2019-0009Transactions on Aerospace Research
Jarosław StanisławskiA SIMULATION MODEL FOR COMPUTING THE LOADS GENERATED AT LANDING SITE DURING HELICOPTER TAKE-OFF OR LANDING OPERATIONROTORCRAFT TECHNOLOGYThe paper presents simulation method and results of calculations determining behavior of helicopter and landing site loads which are generated during phase of the helicopter take-off and landing. For helicopter with whirling rotor standing on ground or touching it, the loads of landing gear depend on the parameters of helicopter movement, occurrence of wind gusts and control of pitch angle of the rotor blades . The considered model of helicopter consists of the fuselage and main transmission treated as rigid bodies connected with elastic elements. The fuselage is supported by landing gear modeled by units of spring and damping elements. The rotor blades are modeled as elastic axes with sets of lumped masses of blade segments distributed along them. The Runge-Kutta method was used to solve the equations of motion of the helicopter model. According to the Galerkin method, it was assumed that the parameters of the elastic blade motion can be treated as a combination of its bending and torsion eigen modes. For calculations, data of a hypothetical light helicopter were applied. Simulation results were presented for the cases of landing helicopter touching ground with different vertical speed and for phase of take-off including influence of rotor speed changes, wind gust and control of blade pitch. The simulation method may help to define the limits of helicopter safe operation on the landing surfaces. helicopter
landing site
landing gear loads
2019225565-8110.2478/TAR-2019-0010Transactions on Aerospace Research
Wiesław Krzymień, Sławomir CieślakINITIAL ANALYSIS OF HELICOPTER IMPACTON HOSPITAL HELIPADSROTORCRAFT TECHNOLOGYThe need to quickly provide assistance to victims of accidents or seriously ill has created the need for the construction of helipads at selected hospitals. Their operation and the conditions of use are governed by regulation of the Ministry of Health on Hospital Emergency Ward (SOR) and rules required by the Civil Aviation Authority. Helipads
helicopter noise
ground tests
2019325614-2310.2478/TAR-2019-0014Transactions on Aerospace Research
Andrzej Chyla, Michał BukałaTHE ANALYSIS OF HOSPITAL HELICOPTER LANDING SITESLOCATION IN TERMS OF THEIR VIBROACOUSTIC IMPACTROTORCRAFT TECHNOLOGYAccording to the applicable regulations, in the case of a decision on the location of an investment consisting in the construction and commissioning of a helicopter landing field, it is necessary to carry out an environmental impact assessment. At the same time, due to the emission of noise related to the expected change of acoustic climate parameters, the indicators required under the applicable law related to building acoustics and also impact of vibration on the structure of buildings should be taken into account. The article discusses particular groups of issues related to the assessment of the impact of helicopter landing field on the environment and the hospital building. On the basis of the presented results of analyzes, a postulate concerning the necessity of introducing a comprehensive assessment methodology, including specific groups of issues, was formulated. helicopter
aircraft
effective persist level
building vibration
2019325643-5610.2478/TAR-2019-0016Transactions on Aerospace Research
Jarosław StanisławskiA Comparison of Helicopter Main Rotor Features due to Stiffness of Rotor Blade-Hub ConnectionRotorcraft technologyThe paper presents results of simulation calculations concerning an influence of stiffness of blade-hub connection on rotor loads and blades deflections in hover, level flight and pull up maneuver. The three versions of rotor are considered with articulated, elastic and stiff connections of blades and hub. The blades with the same distributions of stiffness, mass and the same aerodynamic characteristics are applied for all rotor cases. The rotor loads are calculated applying Runge-Kutta method to solve the equations of motion of deformable blades. According to the Galerkin method, the parameters of blades motion are treated as combination of considered blade bending and torsion eigen modes. The results of calculations indicate for possibility to generate the greater rotor control moments and to improve helicopter maneuverability in the case of applying the non-changed blade of articulated rotor combined with elastic rotor hub. helicopter
main rotor
blade deformations
20181250119-13610.2478/TAR-2018-0008Transactions on Aerospace Research
Mikołaj Górzyński, Przemysław BibikDesigning and Building Heavy Lifting Modification of a Radio Controlled HelicopterROTORCRAFT TECHNOLOGYThe paper presents the heavy lifting modification of radio controlled T-Rex 700 DFC PRO helicopter which was originally designed as acrobatic machine. The purpose of designing machine like this is a need for a cheap and reliable machine specifically designed to carry weights for research and development purposes. Thanks to its design there is a possibility to attach to it a measuring apparatus, modules like auto-pilot, and weights. It can be also used to test wide range of rotors and other components which makes it very universal research tool. To achieve those goals the whole frame and landing gear has been redesigned using NX 11 CAD/CAM/CAE to achieve desired cargo space and weight distribution. Additionally the tail has been lengthened to allow use of the rotors with bigger diagonal. All the applied changes has been made to increase the machine payload. The designed elements were fabricated and the helicopter has been tested in flight. During the test flights several performance parameters were measured. helicopter
rotor
modification
2017424935-4710.2478/TAR-2017-0027Transactions on Aerospace Research
Wieńczysław StalewskiImprovement and Optimisation of Gyroplane PerformanceROTORCRAFT TECHNOLOGYThe aim of this study was to investigate possibilities of improving performance characteristics of light gyroplane, as well to propose new or improved solutions enhancing performance of this type of rotorcraft. The study has been conducted based on computational methods of Computational Fluid Dynamics, Flight Dynamics, Computer Aided Design and Optimisation. Results of the research confirm that using advanced computational methods it is possible to improve significantly the performance characteristics of light gyroplane. It can be achieved both through optimisation of the main rotor design and flight control strategy. An unconventional approach to rotorcraft optimisation has been presented, distinguishing by the fact that the objective was calculated based on computer simulations of selected states of gyroplane flight. One of the optimised main rotors had already been examined during flight tests, which confirmed its good perfonnance-and-exploitation properties and its advantage over classic gyroplane rotors. Developed by the author the family of gyroplane airfoils is a valuable alternative to classic airfoils utilised so far. The same applies to the blades built based on those airfoils. In particular, it concerns the unconventional design of the rotor blade of span-variable: chord and relative thickness. The developed methodology of numerical optimisation of flight-control strategy during the jump takeoff of the gyroplane presents an original approach to those problems and may be valuable tool supporting gyroplane-pilot training. rotorcraft performance
gyroplane
jump takeoff
main rotor
design and optimisation
20174249103-12210.2478/TAR-2017-0031Transactions on Aerospace Research
Mateusz PaszkoInfrared Signature Suppression Systems in Modern Military HelicoptersRotorcraft technologyHelicopters play an important role in air-to-ground fire covering and the short-distance air-to-air fights, as well as the anti-tank missions and battlefield force transferring. The detection and survivability of helicopters on a battlefield significantly depends on their infrared emissions level, as well as the methods, equipment and systems used by potential enemy. The automatic detection systems, recognition and identification of flying objects use among other the thermo-detection methods, which rely on detecting the infrared radiation emitted by the tracked object. Furthermore, due to low-altitude and relatively low flight speed, today’s combat assets like missile weapons equipped with infrared guidance systems are one of the most important threats to the helicopters performing combat missions. Especially meaningful in a helicopter aviation is infrared emission by exhaust gases, egressed to the surroundings. Due to high temperature, exhaust gases are a major factor in detectability of a helicopter performing air combat operations. In order to increase the combat effectiveness and survivability of military helicopters, several different types of the infrared suppressor (IRS) have been developed. This paper reviews contemporary developments in this discipline, with particular examples of the infrared signature suppression systems. infrared
military helicopter
stealth
radiation suppression
2017324863-8310.2478/TAR-2017-0022Transactions on Aerospace Research
Izabela Korzec, Tomasz Łusiak, Martin BugajTests of selected mechanical properties of welded joints in rotorcraft.Rotorcraft technologyThe following article presents experimental use of different ways of inguinal connecting of aircraft elements using TIG (Tungsten Inert Gas), MAG (Metal Active Gas) and arched coated electrode. The object of the research were samples of rotorcraft elements, which were connected to each other by TIG, MAG methods and the coated electrode. The main aim of the research was to determine selected mechanical properties in particular hardness and strength of inguinal joints and then, based on the tests carried out, the best methods were selected. Welding
aerospace components
TIG
MAG
coated electrode
2021126264-7410.2478/TAR-2021-0005Transactions on Aerospace Research
Krzysztof Szafran, Marcin MichalczykVarious Types of the Rotorcraft Design in the Context of Aerospace RegulationsRotorcraft technologyIn the next article on synthesis of regulations, the authors presented the general legal requirements for rotorcraft, which is limited to US regulations, because the vast majority of world regulations are based on them. The Institute of Aviation in Warsaw has developed requirements concerning the construction and operation of rotorcraft in Poland. These requirements constitute an important contribution to the regulations of the Civil Aviation Authority which are in force in the air space of the Republic of Poland. This paper presents the legal situation of rotorcraft and compares the requirements for helicopters and gyroplane. The conclusions highlighted the differences that arise from regulations between helicopters and rotorcraft. The authors have suggested the necessity to separate provisions for the group of windmills, which is implemented in the regulations of the Civil Aviation Authority. The presented work is the second of a planned series of publications in which authors intend to bring some of the issues to the reader about the design aspects of aircraft in selected global aviation regulations. aviation regulations
certification
flight safety
helicopters
rotorcraft
gyroplane
20181250146-15310.2478/TAR-2018-0010Transactions on Aerospace Research
Sławomir Cieślak, Wiesław KrzymieńDrivetrain Noise of the Gyroplane I-28Rotorcraft technologyGyroplanes, as ultralight aircraft, are popular transport vehicles recently. Ultralight aircraft flights take place at a low altitude – their noise is not without effect on people and nature. The localization of the sources of noise and a possibility to decrease the noise of an gyroplane are described in this paper. The rules of design and exploitation of gyroplanes do not define the limits of emitted noise. gyroplane
noise
acoustic camera
beamforming
propeller noise
201812507-1610.2478/TAR-2018-0001Transactions on Aerospace Research
Jan Muchowski, Marek Szumski, Andrzej KrzysiakAerodynamic Concept of the UAV in the Gyrodyne ConfigurationRotorcraft technologyThe article presents an aerodynamic concept of UAV in the gyrodyne configuration, as a more efficient one than the currently used UAV airframe configuration applied for monitoring tasks of power lines and railway infrastructure. A sample task which is realised by conceptual gyrodyne based on monitoring aerial power lines was characterised and described. The assumed idea of UAV was shown in comparison to the currently used aircraft configuration presented in the introduction. Referring to momentum theory, hover efficiency of the multicopter and the helicopter was evaluated. In relation to the helicopter, an initial draft of the airframe conception accompanied by a description of advantages of the gyrodyne configuration was exposed. Problems related to the gyrodyne configuration were emphasised in the summary. aerodynamic concept
UAV
VTOL
gyrodyne
airframe configuration
2018125049-6610.2478/TAR-2018-0005Transactions on Aerospace Research
Wieńczysław StalewskiFlow Control on Helicopter – Rotor Blades via Active Gurney FlapRotorcraft technologyThe Active Gurney Flap (AGF) is a small, flat tab cyclically deployed and retracted at lower surface of the rotor blade near its trailing edge. It is expected that the device may improve performance of modern helicopters. The main goal of presented investigations was to develop research methodology and next to use it in studies on phenomena occurring in the flow around helicopter-rotor blades equipped with AGF. Conducted CFD simulations aimed at validation of the developed methodology as well as at significant supplementing and extension of results of experimental research. Simplified sensitivity analysis has been conducted aiming at determination of geometric and motion-control parameters of the AGF, optimal from point of view of helicopter-performance improvement. Fully three-dimensional simulations of the rotor flight aimed at determination of flight conditions, in which the use of Active Gurney Flaps could significantly improve the rotorcraft performance. helicopter rotor blades
active flow control
Active Gurney Flap
rotorcraft performance
2018125098-11810.2478/TAR-2018-0007Transactions on Aerospace Research
Jakub Wilk, Radosław GuzikowskiValidation of numerical models used for designing the composite blade for ILX-27 rotorcraftROTORCRAFT TECHNOLOGYThe paper presents the validation procedure of the model used in the analysis of the composite blade for the rotor of the ILX-27 rotorcraft, designed and manufactured in the Institute of Aviation, by means of numerical analyses and tests of composite elements. Numerical analysis using finite element method and experimental studies of three research objects made of basic materials comprising the blade structure – carbon-epoxy laminate, glass-epoxy composite made of roving and foam filler – were carried out.
The elements were in the form of four-point bent beams, and for comparison of the results the deflection arrow values in the middle of the beam and axial deformations on the upper and lower surfaces were selected. The procedure allowed to adjust the discrete model to real objects and to verify and correct
the material data used in the strength analysis of the designed blade.
composites,
FEM modelling,
mechanical tests.
2019425723-3110.2478/TAR-2019-0020Transactions on Aerospace Research
Joanna Gocłowska-BolekLatin American Space Research as a Regional and Supra-Regional Research Cooperation MechanismScientific co-operationThe interest of Latin American countries in space research has been successfully developing for many decades. It has its roots in the first development programmes for the Brazilian and Argentinian defence industry within the import substitution strategy, and then the export-oriented strategy during the period of the military rule. The endogenous development of space technology was treated in those countries as a priority and served as a way to diffuse technology to other industries, and as a model for the other countries in the region (Peru and Venezuela), which wished to develop outer space programme by developing their own technologies within the chosen range or by partaking in broader cooperation programmes on the Latin American continent [1]. The Latin American space agencies, which already existed in many countries in the 1960s and the 1970s, were carrying out relatively costly research, treating development in this area not only as the achievement of the economic development objectives, but also as an attempt to oppose the dominance of Washington [2]. Despite of the vast funding on endogenous research in the field of space engineering being provided, until the end of the last century only the projects conducted together with the Soviet Union (Cuba) or The United States were accomplished successfully. Currently and in the nearest future, the Latin American countries are still forced to rely on external assistance with satellite launching, expertise, more advanced technologies, etc. It should be noticed that countries conducting advanced and costly space programmes: the United States, Russia, China and the European Union (especially France and – but to a substantially lesser degree – Italy) show a growing interest in cooperation with Latin America and appreciation towards their specialists, high quality research and space technologies. Latin America
Brazil
space research
innovation
scientific cooperation
2017424924-3410.2478/TAR-2017-0026Transactions on Aerospace Research
Jan Kotlarz, Natalia ZalewskaTHE POSSIBILITY OF ULTRAVIOLET ENCELADUS’ OBSERVATIONS FROM STRATOSPHERIC BALLOONSSPACE OBSERVATIONStratospheric balloons are very important sources for space and terrestrial observation experiments in many disciplines. Instruments developed for astrophysical measurements are usually reusable. It is also possible to observe both hemispheres including observations from the polar and equatorial regions for thirty days or even longer. On the other hand the UV atmospheric transmittance window was used for the astrophysical observations less often than visible optical bands. At the end of the 2017 there are a few scientific groups working on near-UV or UV spectrographs and cameras for balloon flights. stratospheric balloons
Enceladus
ultraviolet
water ice
tholin
2019125417-2710.2478/TAR-2019-0002Transactions on Aerospace Research
Hubert SkonecznyPREPARATION AND IMPLEMENTATION OF A TEST FLIGHT OF LIGHTWEIGHT, UNMANNED STRATOSPHERIC BALLOON WITH GOPRO CAMERA MOUNTED AND ANALYSIS OF ACQUIRED MATERIALSPACE OBSERVATIONPublication contains a description of the preparation and the implementation of a test flight of a stratospheric balloon with a mounted camera GoPro Hero3. Description includes: used equipment, its parameters, role in the success of the mission and the difficulties and limitations that the project team encountered during the preparation and implementation of the flight. The mission was attended by a team of six engineers and scientists from the Remote Sensing Division, who were also involved in the implementation of the HESOFF project. One of the main goals of the HESOFF project was to obtain aerial images on the Krotoszyńska Plate (woj. wielkopolskie) using the Unmanned Aerial Vehicle (UAV) and to carry out remote monitoring of oak stands. The primary goal of an experimental balloon flight was to check the technical operational capability and gain experience in planning and implementing this type of project. During the balloon raising, the video material was acquired in the form of a recording, which later was analyzed. On the basis of the collected information, the conclusions regarding the possibility of implementing a long endurance flight in the stratosphere, illustrating (using a multisensor platform) research surfaces of the HESOFF project were presented. The stages of implementation of the presented mission were divided into following parts: preparation of the flight with the completion of equipment and necessary documents (flight permission), proper flight realization, understood as the release of the balloon and identification of the place where the equipment landed, as well as analysis and presentation of the results. stratospheric balloon
photogrammetric flight
GPS
Unmanned Aerial Vehicle
2019225521-3210.2478/TAR-2019-0007Transactions on Aerospace Research
Marcin Spiralski, Karol Bęben, Wojciech Konior, Dawid CieślińskiHigh Altitude Ballooning as an Atmospheric Sounding System in the Pre-Flight Procedures of ILR-33 AmberSPACE OBSERVATIONThe paper presents research on the near real-time atmospheric sounding system. The main objective of the research was the development and testing of the weather sounding system based on a weather balloon. The system contains a redundant system of radiosondes, a lifting platform containing weather balloon and a holding system as well as ground station. Several tests of the system were performed in August and September 2019. Altitude, reliability, resistance to weather conditions and data convergence were tested. During tests, new procedures for such missions were developed. The final test was performed for the ILR-33 Amber Rocket as a part of pre-launch procedures. The test was successful and allowed to use acquired atmospheric data for further processing. Several post-tests conclusions were drawn.
The altitude of sounding by a weather balloon depends mostly on weather conditions, the amount of gas pumped and the weight of a payload. The launching place and experience of the crew play an important role in the final success of the mission, as well.
weather balloon,
unmanned free balloon, a
tmosphere sounding,
radiosonde,
remote sensing,
Earth observation
2020125866-7710.2478/TAR-2020-0005Transactions on Aerospace Research
Wojciech KoniorParticle-in-cell Electrostatic Numerical AlgorithmSpace observationsExisting global models of interaction between the solar wind (SW) and the local interstellar medium (LISM) describe the heliosphere that arises as a result of this interaction. There is a strong motivation to develop a kinetic model using the Particle-in-Cell (PIC) method to describe phenomena which appear in the heliosphere. This is however a long term scientific goal. This paper describes an electrostatic Particle-in-Cell numerical model developed in the Institute of Aviation in Warsaw, which includes mechanical and charge exchange collisions between particles in the probabilistic manner using Direct Simulation Monte Carlo method. This is the first step into developing simulations of the heliosphere incorporating kinetic effects in collisionless plasmas. In this paper we focus only on presenting the work, which have been done on the numerical PIC algorithm. plasma
neutral particles
Particle-in-Cell
Monte-Carlo Method
2017324824-4510.2478/TAR-2017-0020Transactions on Aerospace Research
Zbigniew GutUsing Electrical Capacitance Tomography System for Determination of Liquids in Rocket and Satellite TanksSPACE TECHNOLOGYOne of important problems in aerospace engineering is to determine the amount of fluid in the tank in a microgravity environment. There are several methods for doing it, however, there are no proven methods to quickly gauge the amount of propellant in a tank in low gravity conditions. New and more accurate methods of such a measurement are being continually searched for. One of interesting solutions is using Electrical Capacitance Tomography (ECT) for this purpose. The article presents both numerical analysis and experimental test results using a spherical tank. The main purpose of the simulation was to determine the effect of the number of electrodes and noise signal level on the quality of reconstruction images. In numerical simulations, different models of dielectric permittivity distribution have been reconstructed. On the basis of numerical simulations, a 24-electrode sensor was designed and made.
In experimental tests, different distribution of medium inside the spherical tank was investigated.
The results show that the method can directly measure the mass of fuel in the tank, as well as it allows for a visualization of fuel distribution, independent of the tank position in space, and the liquid-propellant system will be used.
tomography,
satellite,
tank.
2020125818-3310.2478/TAR-2020-0002Transactions on Aerospace Research
Dagmara StasiowskaCan We be with Bee on Mars? Evaluating the Impact of a Rocket Flight on the Condition of Honeybees (Apis Mellifera)SPACE TECHNOLOGYIn paper the issue of a rocket flight impact and overall survivability of such flight by Apis mellifera (western honeybees) specimens is raised. Author claims that it is the key for using them on Mars for pollination in future, as this species is considered as one of the best pollinators, and should be examined before sending first human missions to the Red Planet. Rocket payload ‘BeeO!Logical’ was designed in order to conduct the research, the first of its kind worldwide. Its assumptions are presented along with overall descriptions of the experiments in two sounding rockets. Analysed data included survivability, carbon dioxide concentration values (respiration levels), temperature and humidity. It has been shown
that A. mellifera specimens are able to survive the rocket flight. Project development possibilities are described, including widening the scope of the research with bumblebees (Bombus) and implementation of biocybernetic model of bee colony.
honeybees,
rocket, payload,
Mars terraformation
2020225936-4610.2478/TAR-2020-0009Transactions on Aerospace Research
Andrzej KotarskiA CONCEPT OF SUBORBITAL SCIENTIFIC MISSIONAND TECHNOLOGY VALIDATIONSpace technologySuborbital platforms are one of alternatives for satellites. They offer cheaper access to space to perform broad range of scientific and technology R&D. One of suborbital platforms are sounding rockets, which are suitable for these applications. A concept of scientific mission utilizing the sounding rocket is presented by author in this paper. The novelty of this mission is the operational responsive launch approach, which presents the example of the mission which responds for payload user needs, not payload contest approach, which is often in scientific community competing for payload space in space agency sounding rocket launch campaigns. The main mission goal is to perform astronomical observation of NEO using IR/VIS telescope. The secondary goal is to qualify the instrument for use on astronomical satellite observatory and raise its technology readiness level from TRL 6 to TRL 8. The expected mission output is to gain scientific data on NEO object and perform new IR/VIS optoelectronic instrument technology validation. Suborbital platforms
sounding rockets
space science
optoelectronic instrument
technology validation
2019325666-7410.2478/TAR-2019-0018Transactions on Aerospace Research
Alfons Mayer, Wolter WielingGreen Propulsion Research at TNO the NetherlandsSpace technologyThis paper describes the recent theoretical and experimental research by the Netherlands Organisation for Applied Scientific Research (TNO) into green replacements for hydrazine, hydrazine derivatives and nitrogen tetroxide, as propellants for in-space propulsion. The goal of the study was to identify propellants that are capable of outperforming the current propellants for space propulsion and are significantly less hazardous for humans and the environment. Two types of propellants were investigated, being monopropellants and bipropellants. The first section of the paper discusses the propellant selection. Nitromethane was found to be the most promising monopropellant. As bipropellant, a combination of hydrogen peroxide (HP) and ethanol was selected, where the ethanol is rendered hypergolic with hydrogen peroxide. The second part of the paper describes the experimental verification of these propellants by means of engine testing. Initiation of the decomposition of nitromethane was found to be problematic, hypergolic ignition of the hydrogen peroxide and ethanol bipropellant however was successfully demonstrated. Green propulsion
monopropellant
bipropellant
hydrogen peroxide
nitromethane
201842531-2410.2478/TAR-2018-0026Transactions on Aerospace Research
Lyubomyr Sabadosh, Serhii Larkov, Oleg Kravchenko, Vladyslav SeredaIncreasingly Safe, High-Energy Propulsion System for Nano-SatellitesSpace technologyNumerous attempts have been undertaken to develop propulsion systems for nano-satellite-type spacecrafts to enable their maneuvering in orbits. One of the potentially viable chemical propellant propulsion systems is a hybrid system. The present paper studies propellant composition variants with the metal hydride as fuel that can be chosen for a nano-satellite hybrid propulsion system. It defines key requirements for chemical propellant nano-satellite propulsion systems, and specifies potential propellant pairs based on a compact metal hydride. The study describes basic technical characteristics of a 1U CubeSat propulsion system. satellite propulsion
metal hydride
hydrogen peroxide
2018425338-4410.2478/TAR-2018-0028Transactions on Aerospace Research
Mateusz Sochacki, Janusz NarkiewiczPropulsion System Modelling for Multi-Satellite Missions Performed by NanosatellitesSpace technologyProgress in miniaturization of satellite components allows complex missions to be performed by small spacecraft. Growing interest in the small satellite sector has led to development of standards such as CubeSat, contributing to lower costs of satellite development and increasing their service competitiveness. Small satellites are seen now as a prospective replacement for conventional sized satellites in the future, providing also services for demanding users. New paradigms of multi-satellite missions such as fractionation and federalization also open up new prospects for applications of small platforms. propulsion
nanosatellite
formation flying
constellations
fractionated satellite
federated satellite systems
2018425358-6710.2478/TAR-2018-0030Transactions on Aerospace Research
Patryk Palej, Tomasz PalaczPreliminary design analysis of regenerative cooling for N2O/Alkohol small scale liquid rocket engineSpace technologyThis paper presents a concept of a small scale liquid-propellant rocket engine designed in AGH Space Systems for sounding rocket. During preliminary design of thermal aspects various ways of cooling were evaluated and described. Possible issues and design approaches for ablative, radiation and regenerative cooling are raised. The authors describe available solutions. Regenerative cooling is especially concerned as it is most popular solution in bi-liquid engines, in which alcohol fuel acts as coolant and is preheated before it reaches combustion chamber. To estimate a possible temperature distribution - and thus an applicability of such a system in the engine - a mathematical model of heat transfer was developed. Unique element of said engine is its oxidizer - nitrous oxide, which have been rarely used to date. Comparison between typical LOX bi-liquids is given and major differences that affect cooling arrangement are discussed. The authors compared different combinations of coolants, fuel/oxidizer ratios etc. to optimize the temperature distribution which is a key factor for the engine performance. liquid rocket engine
regenerative cooling
nitrous oxide
sounding rocket
2018325287-10210.2478/TAR-2018-0024Transactions on Aerospace Research
Adam Rosłowicz, Paweł BednarczykAnalysis of heat transfer in a supersonic rocket headSpace technologyDesign of supersonic H1 rocket by the Rocketry Group of Students’ Space Association (SR SKA) requires an analysis of thermal phenomena occurring in the elements particularly exposed to the high temperature gas. This paper contains a description of the methodology and the results of numerical simulation of heat transfer in the elements of the rocket head. The starting points were the flight conditions (3 characteristic points defined by altitude and Mach number) and independently calculated adiabatic temperature field of the gas. ANSYS Fluent code was used to determine the temperature field on the surface of the rocket. Computed cases were viscous and inviscid flow (for comparison). Based on the results formulated for the viscous case heat transfer boundary conditions, the numerical model and the thermophysical properties of materials were defined. The model was limited to a brass top part of the head and a part of a composite dome. Analytical and empirical method of “intermediate enthalpy” determined distribution of the heat transfer coefficient on the rocket surface. Then the transient heat transfer was calculated with the ANSYS system. It included the range from the rocket launch, moment of maximum Mach number to sufficient structure cooling. The results of the analyses were conclusions relevant to the further development work. Excessive heating of composite structures during the flight has been shown. rocket technology
computational fluid mechanics
unsteady heat transfer
ANSYS software
2017124679-9410.2478/TAR-2017-0008Transactions on Aerospace Research
Ken Wen, De-ning Di, Xiao-wei ChenAn alternative ballistic limit equation for the Whipple shield in the shatter regime, based on characteristics of the large central fragment.Spacecraft designIn the shatter regime of a Whipple shield, a large central fragment makes a significant contribution to the damage-causing capacity of the debris cloud. Herein we present a feasible scheme for the identification and measurement of this large central fragment and propose an alternative approach to the ballistic limit equation (BLE) for the Whipple shield, deducing an alternative ballistic limit in the shatter regime based on the large central fragment’s characteristics. This alternative BLE is compared with the phenomenological Whipple BLE, the JSC Whipple BLE and the Ryan curve. Our alternative BLE, modified at the incipient fragmentation and completed fragmentation point, is shown to agree well with experimental results. Whipple shield
debris cloud
ballistic limit equation
large central fragment
fragment identification
2021226312-2910.2478/TAR-2021-0008Transactions on Aerospace Research
Marco Fioriti, Luca Boggero, Sabrina CorpinoPreliminary Sub-Systems Design Integrated in a Multidisciplinary Design Optimization FrameworkSystemsThe aircraft design is a complex subject since several and completely different design disciplines are involved in the project. Many efforts are made to harmonize and optimize the design trying to combine all disciplines together at the same level of detail. Within the ongoing AGILE (Horizon 2020) research, an aircraft MDO (Multidisciplinary Design Optimization) process is setting up connecting several design tools and competences together. Each tool covers a different design discipline such as aerodynamics, structure, propulsion and systems. This paper focuses on the integration of the sub-system design discipline with the others in order to obtain a complete and optimized aircraft preliminary design. All design parameters used to integrate the sub-system branch with the others are discussed as for their redefinition within the different detail level of the design. Multidisciplinary Design Optimization
Aircraft Sub-system Design
Design Space Parameters
201742499-2310.2478/TAR-2017-0025Transactions on Aerospace Research
Kubiak Katarzyna, Stypułkowska Justyna, Szymański Jakub, Spiralski MarcinEstimation of bare soil moisture from remote sensing indices in the 0.4–2.5 μm spectral range.UAV applicationsSoil moisture content (SMC) is an important element of the environment, influencing water availability for plants and atmospheric parameters, and its monitoring is important for predicting floods or droughts and for weather and climate modeling. Optical methods for measuring soil moisture use spectral reflection analysis in the 350–2500 nm range. Remote sensing is considered to be an effective tool for monitoring soil parameters over large areas and to be more cost effective than in situ measurements. The aim of this study was to assess the SMC of bare soil on the basis of hyperspectral data from the ASD FieldSpec 4 Hi-Res field spectrometer by determining remote sensing indices and visualization based on multispectral data obtained from UAVs. Remote sensing measurements were validated on the basis of field humidity measurements with the HH2 Moisture Meter and ML3 ThetaProbe Soil Moisture Sensor. A strong correlation between terrestrial and remote sensing data was observed for 7 out of 11 selected indexes and the determination coefficient R2 values ranged from 67%– 87%. The best results were obtained for the NINSON index, with determination coefficient values of 87%, NSMI index (83.5%) and NINSOL (81.7%). We conclude that both hyperspectral and multispectral remote sensing data of bare soil moisture are valuable, providing good temporal and spatial resolution of soil moisture distribution in local areas, which is important for monitoring and forecasting local changes in climate. soil moisture content
remote sensing
hyperspectral data
bare soil
UAV
202122631-1110.2478/TAR-2021-0007Transactions on Aerospace Research
Anastasiia Shcherban, Volodymyr IeremenkoUAV flight safety system based on fuzzy logic.UAV SAFETYThe article proposes a method of deciding on the continuation or termination of the UAV flight on the basis of fuzzy logic to ensure its trouble-free flight, which will be used in the future to build an onboard monitoring system of the power supply of the unmanned aerial vehicle. The developed method of decision-making allows to determine the residual battery life on the basis of data on current voltage, battery temperature, temperature on board the UAV and the direction and strength of the wind, using which the computer system will make recommendations for continuing or terminating the UAV flight task. The method of decision-making using fuzzy logic involves the formation of linguistic variables, which are the input information parameters and the output decision, their linguistic terms and membership functions, as well as a system of rules for decision-making. The voltage at the output of
the battery, its surface temperature and the wind direction on board the UAV were used as input variables, and the residual battery life was used as the output linguistic variable
LPAB
unmanned aircraft
fuzzy logic system
method of decision-making
2020426171-8010.2478/TAR-2020-0022Transactions on Aerospace Research