2023

Постійне посилання на фонд

https://ela.kpi.ua/handle/123456789/55463

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Adaptation of corporate model of Ukrainian aircraft product life cycle to the international methodology of systems engineering
(Igor Sikorsky Kyiv Polytechnic Institute, 2023) Kryvova, S.; Zvorykin, C.; Trubachev, S.
Problems. Under the present-day conditions, the preservation of competences of Ukrainian aircraft construction enterprises will be determined by the possibility of enterprises attracting to participation in international cooperation programs and projects. But this is possible only on the condition of prior harmonization of the product development methodology adopted in Ukrainian aircraft construction to that used in the international aircraft construction projects. Purose. The main goal of this article is to determine the ability and ways of adapting the corporate model of life cycle of aircraft engineering projects by Ukrainian aircraft construction enterprises to modern global aircraft construction practices. Implementation methodology. The research methodology predicted the identification of the main modern trends in the field of system engineering for the creation of a science-intensive product, as well as the analysis of concepts of presenting the life cycle of complex technical systems in international regulatory documents, industry regulations, guidelines and other information sources. Criteria for perspective of using the identified informational and normative sources as close analogues for the development of one’s own corporate model of life cycle of an aircraft construction product were identified. On the basis of the criterion analysis of researched concepts of the life cycle of complex technical systems representing, the requirements were formed, which formed the basis of the concept of one’s own corporate model of life cycle of the aircraft construction product. The results. The result of conducted research was the proposed concept of a corporate model of the life cycle of an aircraft construction product manufactured in Ukraine, which takes into account the international experience and best practices of leading aircraft construction companies, including focusing on the experience accumulated by domestic aircraft manufacturers. Conclusions. According to the results of analysis of advanced world practices in the field of creating a science-intensive product, an own corporate model of the life cycle of an aircraft product manufactured in Ukraine was proposed. In the future, on the basis of this model, a system for creating an aircraft product can be built and developed, which will be harmonized with existing world practices and will allow the domestic aircraft construction enterprises to fight for participation in international programs and projects.
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Analysis of spray particles entrance of Right-angle cold spray nozzle based on CFD
(Igor Sikorsky Kyiv Polytechnic Institute, 2023) Tan Kun
Cold spray technology is a solid-state deposition technology, and the nozzle is an important part of the cold spray system. This article proposes a right-angle nozzle. The characteristic of this nozzle is that it can change the flow direction of the gas flow inside the nozzle to realize spraying on the surface of special parts; the acceleration of particles by the right-angle nozzle with different particle entrances is studied. The results show that the outlet center velocity of the right-angle nozzle with a circular throat section is greater, the viscous boundary layer effect is better, and the effective circulation area is larger; the maximum airflow velocity near the outlet of the right-angle nozzle at the particle entrance A is 663.4m/s; it can also effectively avoid the deposition of particles inside the right-angle nozzle, thereby reducing the loss of kinetic energy during the acceleration of particles in the right-angle nozzle; the research on the structure of the new right-angle cold spray nozzle can provide reference for the nozzle of cold spray technology Opinion.
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Analysis of the forces acting from the side of the magneto-abrasive tool on parts being machined during magneto-abrasive machining in conditions of the annular bath with large working gaps
(Igor Sikorsky Kyiv Polytechnic Institute, 2023) Maiboroda, V.S.; Dzhulii, D.Yu.; Zastavskyi, K.O.
Background. For effective magneto-abrasive machining (MAM) of complex-shaped parts, comprehensive information is needed on the processes that occur when the magneto-abrasive tool (MAT) contacts with the surfaces being machined. Effective magneto-abrasive machining occurs in the presence of sufficient values of the normal and tangential components of the interaction forces between the MAT and the machined surfaces and the powder mixing during machining. Previously carried out analytical studies of dynamic parameters did not take into account the real conditions of the interaction of grains and their groups with machined surfaces.
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Analysis of the influence parameters on steel strip defects in continuous roll casting-rolling
(Igor Sikorsky Kyiv Polytechnic Institute, 2023) Nogovitsyn, O. V.; Kholiavik, O. V.; Boris, R. S.; Sokhan, D. V.; Seminska, N. V.
Problems. The casting-rolling process is currently one of the most effective and promising processes used for the production of steel sheets. The advantages of this process include the small dimensions of the unit and a significant reduction in energy resources. This occurs due to a combination of technological operations and absence of the intermediate heating of the metal. At the same time, there is the challenge of a sustainable industrial process for producing high quality steel sheets. Objective. Companies developing direct melt strip processes using twin-roll crystallizers report a number of challenges they face. Among such problems are defects on the surface of the cast strip. Currently, there is no generally accepted classification of surface defects, such as surface cracks, wrinkles, namely, depressions, and transverse deformation bands. At the moment, there is also no justification for the reasons for the appearance of surface defects during the rolling process. Methods. Based on the research results, a hypothesis was proposed about the causes of defects on the surface of the cast strip and ways to prevent them. During the operation of two-roll crystallizers, a combination of metal hardening processes and its subsequent plastic deformation occurs. The metal moves sequentially through areas of crystallization and deformation. During the research, the authors calculated the process of roll casting-rolling. Conclusions. Based on the research results, we believe that when casting steel using twin-roll casting-rolling, it is necessary to reduce the compression to a minimum value. This recommendation will ensure welding of defects on the surface. The use of this proposal will allow the casting process to be carried out at high speed and little force to be applied to squeeze the rolls. We propose to carry out the process of forming a cast strip with the necessary quality parameters at the following stages of rolling.
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Assignment of the cutting mode when boring holes on CNC machine
(Igor Sikorsky Kyiv Polytechnic Institute, 2023) Petrakov, Y. V.; Danylchenko, M. А.
Abstract. Due to structural limitations, the processes of boring holes are performed in a low-rigidity machining system, which predetermines their susceptibility to vibrations. The article is devoted to the study of the process of boring holes on CNC machines, and the subject of the study is the effect of the cutting mode on the stability of the machining. The mathematical model of the machining system is presented in the form of a two-mass dynamic system, which forms a closed loop structure with negative feedback by elastic displacement. In addition, positive feedback is taken into account through the delay argument function, which represents machining along traces. It has been proven that this process provokes the emergence of regenerative oscillations in the machining system. The application of the system’s approach made it possible to obtain a mathematical model in the form of state variables, which is acceptable for the use of numerical modeling methods in both time and frequency space. An applied engineering program for determining the stability diagram in “cutting depth - spindle speed” coordinates has been created. The program uses a new criterion of stability of systems closed through positive feedback loop with a delay argument function. For the first time, the validity of such a criterion was proved for systems described by differential equations of the fourth order. The importance of taking into account the results of the study in the form of a stability lobes diagram when assigning a cutting mode, especially in the area of high speeds, is proven. Thus, according to the results of the experiments, a change in speed of only 7% from 2150 rpm to 2320 rpm with the same cutting depth of 0.4 mm allows the process to become stable. The use of the created program is possible in the system of automatic control of the online cutting mode when the machine is equipped with vibration sensors with appropriate systems for identifying the dynamic parameters of the machining system, which will significantly increase the machining efficiency.
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Determination of the KIC Fracture Toughness of the X210Cr12 High-Strength Material
(Igor Sikorsky Kyiv Polytechnic Institute, 2023) ATEŞ, Ergun
It is an important problem that the machines become unusable due to the deformation of the machine elements produced before the planned time. In this study, it was aimed to determine the KIC value of X210Cr12, which is a high strength material. In this way, more accurate load values can be used in the design. Methods: In the experimental study to determine the KIC value, the sample geometry, the crack depth, the load-dependent parameters and calculations and some conformity checks were carried out. Experimental system; KIC consists of 3-point flexure specimens, a press, an electronic circuit capable of detecting the change in load crack opening, and a logger. Findings: In the study, the loads were determined from experimental graphs. Subsequently, load-crack opening values were determined. With these data, the KIC values were calculated as 719,7 and 839,7 MPa.mm1/2 as the minumum and maximum values, respectively. Conclusion: The experimental graphs are in the form of curves that break abruptly with unstable crack propagation without showing plastic deformation. There is no study in the literature on the KIC value of X210Cr12 and it has been determined that it has a low KIC value compared to the high-strength steels studied. It is valuable to determine the KIC value, as fracture problems may occur in designs prepared with the material. The results of the study are data at room temperature.
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Effective decoupling method for derivation of eigenfunctions for closed cylindrical shell
(Igor Sikorsky Kyiv Polytechnic Institute, 2023) Yudin, H.; Orynyak, I.
By expansion into Fourier series along the circumferential coordinate, the problem for elastic thin-walled closed cylindrical shell is reduced to 8th order differential equation with respect to axial coordinate. In spite that the general structure of eigenvalues for this equation was known starting from 60-s of last century, they were derived only to some simplified versions of the shell theory. So, the main goal of paper consists in development of the general procedure for determination of the eigenvalues. The idea is based on that the theory of shell is actually formed by two much simple problems: the plane task of elasticity and the plate problem, each of them is reduced to much easily treated biquadratic equation. So, we start from either of two problems (main problem) while not taking into account the impact from another (auxiliary) problem. After computing its eigenfunctions, we gradually introduce the influence of auxiliary problem by presenting its functions as linear combination of functions for main problem. The results of calculation show the perfect accuracy of the method for any desired number of significant digits in eigenvalues. The comparison with known results for concentrated radial force shows the perfect ability to solve any boundary problem with any desirable accuracy.
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Ensuring accuracy of contour milling on CNC machines
(Igor Sikorsky Kyiv Polytechnic Institute, 2023) Petrakov, Y.V.; Romanov., Y. S
Contour milling is characterized by quasi-stationary, which leads to the occurrence of a machining error caused by elastic deflections of the machining system. Moreover, such an error cannot be eliminated by sub-adjusting the control program “for size”, since it not is constant and changes along the contour in a wide range. To ensure the accuracy of contour milling, a new method of combined control is proposed, which uses a posteriori information of machine verification measurements of the machined surface and a priori information of modeling the material removal process. In case of single manufacturing, the allowance on the last pass is divided into two parts, and after machining the first part, verifications are performed, then modeling and machining of the second half according to the corrected control program. In mass manufacturing, verifications are performed on the first part, and all subsequent ones are machined according to the adjusted control program. To obtain the necessary a posteriori information, the technology of machine verifications on CNC-machine with a three-coordinate probe according to standard control programs is proposed, and it is enough to perform two measurements or one, in the presence of surfaces inclined to the coordinate axes of the contour. A computer program was created, the core of which is a mathematical model of the process, which reproduces the structural diagram of the machining system closed behind two elastic deflections. The primary control file is loaded in G-codes with measurement data, and as a result of the process simulation, a new control file for the CNC-machine tool is formed, which eliminates the error from elastic deflections of machining system. Preliminary tests showed the possibility of increasing the accuracy of contour machining by more than 3 times.
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Features of the welded seam material crystallization in Ti-TiB alloy under electron-beam welding conditions
(Igor Sikorsky Kyiv Polytechnic Institute, 2023) Loboda, Petro; Zvorykin, Volodymyr; Zvorykin, Constantine; Vrzhyzhevskyi, Eduard; Taranova, Tatjana; Kostin, Valery; Zvorykin, Leonid
Natural metal composite materials represent a promising class of modern structural materials that need to be welded. Such materials can be welded by fusion, as has been established with the Ti-TiB alloy as an example. The enhanced operational properties of such materials are determined by the microstructure, which is characterized by the presence of microfibers of borides, carbides, or silicides in the metal matrix. To preserve the mechanical properties of materials in a welded joint, it is necessary to ensure the formation of reinforcing microfibers in the welded seam material. Determination of formation mechanism of boride microfibers, originated in the welded seam material, will become the basis for optimizing of fusion welding modes, in particular, electron beam welding mode. The purpose of this study is the determination of formation mechanism of boride microfibers originated in the welded seam material. Two most probable variants of the formation mechanism are analyzed, which involve eutectic decomposition during crystallization from a liquid melt or eutectoid decomposition from a metastable crystallized alloy. The third version is a mixed variant of the two above-mentioned mechanisms. In the article the results of metallographic analysis of features of boride phase distribution and an analysis of elemental composition of boride fibers based on local Auger electron spectroscopy are presented. The object of study was a Ti-TiB alloy joint obtained by electron-beam welding. The analysis factors were the features of size, orientation, and nature of the distribution of boride phase microfibers in different areas of the welded seam. The characteristic elemental composition of boride microfibers, which characterizes the correspondence to equilibrium phases, is also studied. The degree of deviation of the ratio of boron and titanium in such a phase from the thermodynamically equilibrium in different layers of the material of the welded seam, formed by an electron beam in vacuum, is determined. The dependence of boride phase distribution under various conditions of heat exchange in the welded seam material on the side surfaces and in the central regions is established. It is shown that some of boride microfibers formed in the material of the welded seam are characterized by a deviation from the thermodynamically stable composition ТіВn (n = 1) to ТіВn (n = 0.85). The dendritic nature of boride microfibers distribution and the presence of meta-stable phase formations on Ti and B basis provide the grounds for proposing the predominant mechanism for the formation of structure of the welded seam material in the Ti-TiB alloy during crystallization. An analysis of hypothetical variants of the formation mechanism of boride microfibers originated in the welded seam material showed that the formation of a dendritic type of structure is characteristic for the growth of crystals of a new phase in the liquid phase. Such growth is characterized by the formation of equilibrium phases. The presence of a significant amount of non-equilibrium boride phase in the welded seam indicates the residue of non-equilibrium boron in the titanium matrix and continuation of growing of boride fibers in the crystallized welded seam. A determined mechanism for formation of boride microfibers originated in the welded seam material is eutectic decomposition during crystallization from a liquid melt with the formation of TiB microfibers and further growth of such crystals due to eutectoid decomposition from a metastable crystallized Ti-TiB alloy. The results obtained make it possible to understand the mechanism of formation of a welded seam in welded natural-composite metal materials, which permits to develop the recommendations for optimizing the welding technology for such materials.
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Formation and development of ventilated supercavity past the disk–cavitator in accelerated motion
(Igor Sikorsky Kyiv Polytechnic Institute, 2023) Moroz, V.; Kochin, V.; Semenenko, V.; Naumova, O.
Аbstract. The work is devoted to both the experimental studies and the computer simulation of the process of formation and development of a ventilated supercavity past the disk-cavitator in accelerated motion from the state of rest to the steady velocity. A series of experiments were carried out in the high-speed experimental tank at the Institute of Hydromechanics of the National Academy of Sciences of Ukraine for various values of the air-supply rate into the cavity. It has been established that the portion type of air-loss from the cavity is always preserved in the case of horizontal accelerated motion, while the air-loss by vortex tubes is always realized in the case of steady motion with the same velocity. In this case, shape of the cross sections of the unsteady cavity is close to circular one along the whole cavity length and at all stages of acceleration. To describe this process, a modified mathematical model is proposed that is based on the G.V. Logvinovich principle of independence of the cavity section expansion. An analysis of the influence of both the immersion depth and the air-supply rate on the process of development of a ventilated supercavity during acceleration has been performed by the way of computer simulation.
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Method of matched sections in application to thin-walled and Mindlin rectangular plates
(Igor Sikorsky Kyiv Polytechnic Institute, 2023) Orynyak, I.; Danylenko, K.
The paper elaborates the principally new variant of finite element method in application to plate problem. It differs from classical FEM approach by, at least, three points. First, it uses the strong differential formulation rather than the weak one and suppose the approximate analytical solution of all differential equations. Second, it explicitly uses all geometrical and physical parameters in the procedure of solution, rather than some chosen ones, for example, displacement and angles of rotation as usually done in FEM formulation. Third, the conjugation between adjacent elements occurs between the adjacent sections rather than in polygon vertexes. These conditions require the continuity of displacements, angles, moments and forces. Each side of rectangular elements is characterized by 6 main parameters, so, at whole there are 24 parameters for each rectangular element. The right and upper sides’ parameters are considered as output ones, and they are related with lower and left sides ones by matrix equations, which allows to apply transfer matrix method for the compilation of the resulting system of equations for the whole plate. The numerical examples for the thin-walled and Mindlin plates show the high efficiency and accuracy of the method.
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Prediction of drag coefficient of a hybrid body design of aircraft
(Igor Sikorsky Kyiv Polytechnic Institute, 2023) Viswanath, Shreya; Vasan, Riya; Gopalan, Venkatachalam; Satonkar, Nilesh
This study presents a design of a quintessential hybrid body aircraft, a blended NACA 4414 airfoil winged body. The Design of Elements approach, via Response Surface Methodology (RSM), is used to evaluate the influence of frontal area, chamber angle and materials on the drag coefficient. The Analysis of Variance (ANOVA) is carried out to find the influences of the same. In order to minimize the simulations, a model in RSM, Central Composite Design (CCD) is used. The results of the same are verified via Computational Fluid Dynamics (CFD) simulations. Moreover, combinations of shape memory polymers with composites and graphene nano powder are proposed, for light-weighting and enhanced mechanical properties. A comparison of said materials with commercially used aluminum alloys is done. It is found that the lowest drag coefficient is achievable at a frontal area of 1625 m2 with an angle of attack of –10° and with a material combination of carbon fiber reinforced polymer, glass fiber reinforced polymer, and 10% graphene nano powder by weight.
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Progressive technologies of electrophysical treatment for regulation of stress-strain states of elements of welded structures
(Igor Sikorsky Kyiv Polytechnic Institute, 2023) Lobanov, L.; Ustymenko, P.; Sydorenko, Yu.; Pashchyn, M.
The development of industry stimulates the development of modern approaches to the optimization of welded structures. The use of pulsed electromagnetic fields, plasma currents, electrodynamic forces and their combined effects is a new trend in engineering practice to improve the mechanical characteristics of metal materials and welded joints (WJ). Treatment with a pulsed electromagnetic field (TwPEMF) is a promising direction for optimizing the stress-strain states (SSS) of welded structures made of non-ferromagnetic metal materials. Using the method of electronic speckle interferometry, the effect of TwPEMF on the SSS of specimens of circumferential WJ with a thickness of = 1.0 mm from aluminium AMg6 alloy was investigated. Based on the original procedure using an accelerometer, the kinetics of the action of the force P of the magnetic field pressure on the residual displacements f and SSS of the specimens during their TwPEMF were investigated. TwPEMF of WJ specimens was performed without and with the use of an additional shield made of AMg6 alloy = 5.0 mm. It was found that the use of a shield increases the amplitude values of force P by up to two times, which is caused by an increase in the active volume of the conductive medium. At the same time, TwPEMF without and with the use of a shield contributes to the reduction of f values by 2 and 4 times, respectively, and residual SSS by 50 and 80%. On the basis of mathematical modelling, the advantages of using electrodynamic treatment (EDT) of butt WJ = 3.0 mm of АMg61 (1561) alloy in the TIG welding process compared to EDT at room temperature (Tk) are substantiated. According to the results of the model verification, it was proved that EDT during TIG contributes to the formation of peak values of residual compressive stresses in the weld zone by 60% more than EDT during Tk. The use of a pulsed barrier discharge (PBD), which generates a low-temperature plasma on the surface of the metal being treated, contributes to the optimization of its structure. An increase in the hardness HV of structural 25KhGNMT steel as a result of its PBD treatment from 420 to 510 units was established, which is accompanied by the dispersion of the metal microstructure.
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Semi-analytical implicit direct time integration method for 1-D gas dynamic problem
(Igor Sikorsky Kyiv Polytechnic Institute, 2023) Orynyak, I.; Kostyushko, I.; Mazuryk, R.
Sharp wave treatment for 1-D gas dynamic problem is still a challenge for modern numerical methods. They often require too many space and time steps, produce spurious oscillation of solution, exhibit a strong numerical dissipation or divergence of results. This paper is further extension of authors’ idea of employment the analytical solution for space coordinate, where time step is a parameter which used in the space solution. Its peculiarity consists in development of additional linearization procedure of dependence between the pressure and density. It is performed in premise that actual pressure for each space element is close to the basic pressure, attained at previous moment of time. The efficiency of method is tested on the very popular task of Sod, where two different ideal gases in a tube are separated by diaphragm, which is suddenly broken. The problem considered in Lagrangian coordinates formulation. The results obtained show the very good method efficiency, which requires the essentially lesser time and space steps, leads to no spurious oscillation and give consistent and predictable results with respect to meshing. The accuracy of method is mostly controlled by time step, which should be larger than clearly stated theoretical lower limit. Other advantage of method is that it can calculate the process to any desired time moment, and space meshing can be variable in time and space and can be easily adapted during the process of calculation.
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Taking into account a location of aircraft’s center of mass during motion cuing
(Igor Sikorsky Kyiv Polytechnic Institute, 2023) Kabanyachyi, V. V.; Hrytsan, S. V.; Yankovskyi, S. S.
Compared to other information sources, motion cues provide a pilot with anticipatory information about spatial position and movement of aircraft. For motion cueing a flight simulator cockpit is installed on a motion system, movement of which motion cueing. Therefore, motion system is one of the most important components of full flight simulators. The problem of effective use of constructive resources of six-degrees of freedom synergistic motion system has been solved. But the problem of improving the motion cueing re- mained unsolved, due to the fact that location of motion system center of rotation is significantly different from location of aircraf’s center of gravity, and motion cues differ from real, flight one. The study subject is motion cueing on flight simulators. The problem was solved on the basis of simplified operator for transformation of motion system movements along individual degrees of freedom into jack movements, cubic spline functions to describe the dependence of the centers of rotation along pitch and yaw, and optimization theory using the deformable polyhedron method. The formulated and solved problem of taking into account of location of aircraft’s center of gravity during motion cueing along pitch and yaw increases an efficiency of using of constructive resource of a six-degrees of freedom synergistic motion system, a motion cueing fidelity and training realism on flight simulator.
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The possibility of detecting non-x-ray fragments in the body of the wounded by the contact method
(Igor Sikorsky Kyiv Polytechnic Institute, 2023) Salenko, O. F.; Danylchenko, Yu. M.; Cherniak, V. A.; Оrel, V. М.; Datsenko, V. M.; Salenko, B. О.; Karpenko, К. К.
The types of injuries and types of striking elements were analyzed, the conditions of patients requiring urgent surgical intervention were assessed. The possibilities of existing means of diagnosing fragments in the patient’s body were analyzed, and it was concluded that for non-X-ray contrast fragments, the proposed method of mechanical contact with a special flexible and elastic probe is appropriate and effective. A special tool for examining wound canals has been developed, consisting of a flexible probe for individual use and a handle-holder with a microphone capsule, the membrane of which is directly connected to the probe and reacts to mechanical contact with an obstacle, and the capsule itself is directly connected to the oscilloscope through a signal amplifier. which has spectral signal processing circuits. The problem of the interaction of the elastic contact of a non-rigid element with a fragment located in a viscous medium is set, provided that the properties of the medium are not constant. Typical solutions of this problem for various types of fragments and parameters of the contacting element itself are presented. A picture of the noise emission accompanying the contact is shown. The functional dependence of noise emission parameters on the shape and type of the foreign object in the wound canal was revealed. The expediency of using the frequency-amplitude characteristic of noise radiation as a controlled parameter has been proven. A conclusion was made about the functional conditioning of the width of the signal spectrum and basic frequencies at the time of mechanical contact with a foreign object in the wound, depending on its shape and type; it was established that the use of an oscilloscope with a spectral analysis channel allows for the fairly accurate identification of a non-radiocontrast foreign object in a wound.
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Vacuum plasma erosion resistant 2D nanocomposite coating Avinit for compressor blades of gas turbine engines of aircraft engines
(Igor Sikorsky Kyiv Polytechnic Institute, 2023) Sagalovych, A.; Popov, V.; Kononyhin, A.; Sagalovych, V.; Dudnik, S.; Prokopenko, A.
The work is devoted to the search for new vacuum-plasma coatings with high hardness to increase the durability of the compressor blades of the GTE of aircraft engines Ti-Al-N-based vacuum-plasma coatings obtained by Avinit technologies, which ensure the application of hard, high-quality coatings with dramatically reduced micro-arc damage, were selected as candidates. Avinit multilayer coatings have higher functional characteristics than TiN (microhardness, crack resistance, temperature resistance, erosion and corrosion resistance) and may be promising for applying erosion-resistant coatings for compressor blades. Avinit technologies are technologically closest to the vacuum-plasma technologies used in industrial production for applying TiN protective coatings. New multi-layered 2D nanocomposite wear-resistant ion-plasma hard coatings Avinit (TiN-AlN)n have been developed. The created software products made it possible to reach a qualitatively new level in terms of further modification and improvement of the designs of Avinit functional coatings, stability of technologies and improvement of their quality control when applying such coatings for use in the production of compressor blades of gas turbine engines of aircraft engines. Special attention is paid to methods of preliminary ion-plasma treatment of surfaces before coating. Metallographic studies of the chemical and phase composition and structure of Avinit (TiN-AlN)n coatings have been carried out. The thickness of the coatings is 7–9 μm, the microhardness is 34–35 GPa (compared to the serially used TiN coating: 27.4 GPa). The use of three-stage ion-plasma treatment in Avinit technologies using a double vacuum-arc discharge followed by the application of strengthening coatings in a single technological cycle eliminates the formation of cracks and ensures the production of tightly bonded, high-quality coatings of a given composition with the maximally reduced share of the droplet component. The developed coatings (TiN-AlN)n were applied to experimental batches of working compressor blades of GTE aircraft engines for bench tests.
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Автоматизація процедури визначення допустимості ерозійно-корозійного зносу в трубопроводах АЕС із вуглецевих сталей
(Igor Sikorsky Kyiv Polytechnic Institute, 2023) Ворона, Г. В.; Ананченко, М. С.; Махненко, О. В.
Багато трубопроводів на українських АЕС перебувають в експлуатації більше 30 років, і визначення допустимості дефектів ерозійно-корозійного зносу (ЕКЗ) металу стінки трубопроводу є на теперішній час однією з актуальних проблем атомної енергетики України. Проведено порівняльний аналіз визначення допустимості стоншення стінки трубопроводу внаслідок ЕКЗ за прийнятою в дію ДП НАЕК “Енергоатом” методикою “МТ-Т.0.03.224-18” та керівництвом, заснованому на використанні нормативних документів на проектування елементів трубопроводів. Використання методики продемонструвало значні переваги з точки зору зниження консервативності оцінки ЕКЗ, особливо для стоншень невеликих розмірів, а також для трубопроводів під тиском нижче 60–80 кгс/см2, що дозволяє значно скоротити об’єми ремонтних робіт. Але впровадження методики на практиці може бути пов’язане з проблемами через складність та трудомісткість процедури розрахункової оцінки для персоналу АЕС. Тому для автоматизації виконання оцінки допустимості ЕКЗ в трубопроводі згідно вимог методики було розроблено програмне забезпечення (ПЗ) для використання персоналом АЕС, яке дозволяє оперативне отримувати протокол процедури експрес оцінки допустимості ЕКЗ прямолінійної ділянки трубопроводу на основі результатів вимірювання параметрів стоншення стінки в осьовому напрямку, а саме зробити висновок: чи ділянка може бути допущена до експлуатації, має бути відправлена на ремонт або необхідне проведення уточненої оцінки. Також розроблено ПЗ на основі методу скінченних елементів (МСЕ), що при необхідності дозволяє проводити уточнену оцінку для прямолінійної ділянки, враховуючи глибину і кут стоншення в окружному напрямку, і розраховувати напруження граничного пластичного стану ділянки трубопроводу з ЕКЗ з точки зору в’язкого руйнування. Область застосування розробки – атомна енергетика України.
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Альтернативні технології композитних високонавантажених авіаконструкцій: якісний метод прийняття багатокритеріальних рішень: III частина. Дослідження методологічної основи в прийнятті рішень: технологічні конструкти в інструментарії оцінки
(Igor Sikorsky Kyiv Polytechnic Institute, 2023) Забашта, В. Ф.
Третя частина статті виходить з відправних положень в задачі прийняття рішень (ЗПР), зазначених на перших етапах досліджень. Тут продовжено зіставлення за превалюванням (найперше – якість) автоклавних та безавтоклавних альтернативних технологічних процесів (АТП) у складі етапів ТП(е) з лінійним алгоритмом наскрізної дії при виготовленні вуглепластикових (ВП) авіаконструкцій (АК) типу високонавантажених стрингерних панелей кесона крила (ВСП) магістральних літаків В787, А350, МС – 21, CSeries, як складник ієрархічних систем. Для їх опису та вивчення були залучені: вихідні технолого-вербальні моделі, технолого-математична модель автономної динамічної системи (АДС) та низка двовимірних ,багатовидів (топологія) до неї у вигляді технолого-геометричних моделей. В статті продовжені дослідження розвитку в цьому напрямку шляхом апроксимації багатовидів багатогранниками. В тому числі коміркових та подвійно сформованих структур – п’ятикутні піраміди та біпіраміди, а також тіла обертання навколо них – конус та біконус. Представлені приклади схемотехнологічного інтерпретативного моделювання. За методологічну основу взяті головні положення теорії прийняття рішень, факторного аналізу та системно-процесний підхід з залученням результатів практики(експертний аналіз), в першу чергу – визначення технологічних чинників процесів з критеріальними оцінками щодо переваг, компонентів альтернатив в їх конкурентних стратегіях.
Відкритий доступ
Аналіз технічного рівня об’ємних гідроприводів з мотор-колесами
(Igor Sikorsky Kyiv Polytechnic Institute, 2023) Аврунін, Г. А.; Подригало, М. А.; Мороз, І. І.; Коваль, О. Д.
Проведений аналіз використання об’ємних гідроприводів обертання гідромотор-коліс для гусеничних та колісних машин. Розглянутігідравлічні принципові схеми застосування швидкісних аксіально-поршневих гідромоторів з планетарними редукторами та високомоментних радіально-поршневих гідромоторів, зокрема гідропристроїв для забезпечення надійного пересування при виникненні перешкод з боку дорожнього покриття. Показані особливості методики статичного і динамічного розрахунку з використанням математичної моделі для чисельного розв’язання диференціальних рівнянь при розрахунку коливань тиску та частоти обертання гідромоторів залежно від завдань інтенсивності зміни подачі насоса та робочого об’єму гідромотора з урахуванням його ККД. Проведений порівняльний аналіз технічного рівня гідромотор-коліс та виявлено суттєво підвищення вихідних параметрів високомоментних радіально-поршневих гідромоторів щодо тиску, частоти обертання та відношення маси до крутного моменту. Стаття може бути корисної для інженерів, науковців та студентівмагістрів.

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