Aerospace technic and technology最新文献

{"title":"Використання термоакустичних технологій в суднових гібридних енергетичних установках з паливними комірками","authors":"V. Korobko, Anatoliy Shevtsov","doi":"10.32620/aktt.2023.4.11","DOIUrl":"https://doi.org/10.32620/aktt.2023.4.11","url":null,"abstract":"Recently, hybrid power plants have gained significant popularity in marine energy systems. These power plants, in addition to traditional thermal engines, include electrochemical power generation systems based on fuel cells. Hybrid marine power plants represent a relatively new technical solution for the maritime fleet, driven by strict environmental emission regulations imposed by international organizations. These regulations primarily target greenhouse gas (GHG) emissions, such as carbon oxides, methane, nitrogen oxides, and other compounds. An analysis of the current state of marine energy and its development trends concludes that the problem lies in the working processes of thermal engines, which are based on fuel combustion. Achieving ecological cleanliness in maritime transport is possible by transitioning to new principles of mechanical energy production that do not rely on chemical fuel combustion. Fuel cells, which generate electricity through electrochemical processes, have the potential to solve this problem. However, the implementation of such electrochemical generators requires a systematic approach to the development of schematic solutions capable of achieving a synergistic effect. The subject of the research is the regularities and parameters of energy exchange processes in hybrid power plants. This study focuses on hybrid power plants with electrochemical generators based on proton exchange membrane fuel cells (PEM FC). The effective operation of hybrid power plants involves the utilization of waste heat from ship equipment. PEM FC is the most widely used type of fuel cell in energy and transportation sectors. The operating temperatures of PEM FCs, depending on their type, range from 60 to 80°C or 120 to 200°C, which poses a challenge for the development of efficient waste heat utilization systems. The aim of the research is to develop waste heat utilization schemes for hybrid power plants with PEM FCs using thermoacoustic heat engines. The study establishes that electrochemical generators can be integrated into the thermal system of modern power plants, and the application of thermoacoustic heat engines expands the potential of waste heat utilization systems. Low-temperature thermoacoustic engines have the capability to convert waste heat generated by PEM FC systems into mechanical work, thereby increasing the overall efficiency of hybrid power plants by 8 to 15%.","PeriodicalId":418062,"journal":{"name":"Aerospace technic and technology","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126615658","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Коефіцієнт гідравлічного опору тертя капілярів за малих чисел Рейнольдса","authors":"Oleh Selezen, Mark Shliakhov, R. Orlov","doi":"10.32620/aktt.2023.4.03","DOIUrl":"https://doi.org/10.32620/aktt.2023.4.03","url":null,"abstract":"Heat transfer pump circuits with liquid or two-phase heat transfer fluids are widely used in thermal management systems in both space and ground applications. These systems play an important role in maintaining the optimal temperature and heat distribution in various processes and devices. Such systems use throttles to ensure efficient distribution of coolant flows through the hydraulic network. It is especially important to ensure the reliability of the system at low coolant consumption. Therefore, a rational approach is to manufacture throttles in the form of capillary segments. Capillary throttles can regulate the flow of coolant with high accuracy, which makes it possible to improve control over the thermal regime of the system. To calculate and determine the characteristics of such throttles, it is important to know the coefficient of hydraulic friction resistance λ, which is used in the Darcy formula. This coefficient depends on various factors, including the geometry of the throttle, physical properties of the heat transfer fluid, and flow conditions. Therefore, the aim of this study was to determine the value of the hydraulic friction resistance coefficient λ. In this work, experiments were performed with the shedding of copper capillaries of different internal diameters (0.8-1.2 mm) in water and isopropyl alcohol. The experiments were carried out in the laminar and transient regions, in the range of Reynolds numbers from 250 to 6050. Conclusions. In the laminar region (Re < 1185), it is recommended to use the Poiseuille formula. In the transitional and turbulent regions (1185 < Re < 6050), it is recommended to use the Blasius formula. The results of the experiments made it possible to obtain data on the value of the hydraulic friction resistance coefficient λ. These data can be used to calculate throttles in similar heat transfer systems. Moreover, the paper provides recommendations on the use of well-known formulas for calculating throttles, which allows engineers and designers to effectively implement these elements in their projects. Thus, the research conducted in this paper has important practical implications for the development and optimization of heat transfer systems in space and terrestrial applications.","PeriodicalId":418062,"journal":{"name":"Aerospace technic and technology","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128115702","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of the autorotation stability of a turbofan engine with a detached fan blade","authors":"Sergey Filipkovskij, Valentin Chigrin, Alexandr Soboliev, Yevgeny Vasilevskij, Nikolay Topal, Larisa Filipkovska","doi":"10.32620/aktt.2023.4sup1.02","DOIUrl":"https://doi.org/10.32620/aktt.2023.4sup1.02","url":null,"abstract":"One of the requirements for the aircraft being designed is the ability to continue flying and landing if one engine fails. One of the calculated cases of engine failure is the separation of the fan blade. This phenomenon causes large vibrations in both the engine itself and the aircraft structure. A calculation model and method for studying engine oscillations with damage in the form of blade separation have been developed. Numerical studies of the oscillations of the engine suspended on a pylon were conducted. The operation of an engine with an unbalance of the fan after switching off during the transition to autorotation is considered. Numerical simulation was performed using the ANSYS Workbench package. The front supports of the rotors are ball bearings installed in the elastic elements of the \"squirrel cage\". Ball bearings are modeled as a rigid hinge. There are two thin-walled shells, which are intermediate power elements outside the elastic element. With an increase in the imbalance of the fan rotor, the gap in the oil damper closes, the damper housing sits on the shells, switching on their rigidity to work. Thus the support stiffness characteristic is bilinear. The stiffness coefficients of the elastic element \"squirrel cage\" and the shells of the front support are determined by numerical simulation. The fan rotor is modeled as a rigid body on bearings. The motor stator is modeled by a rigid body on an elastic suspension. The pylon and elements of the elastic suspension of the engine are modeled by beams of variable section, working simultaneously in tension, torsion, and bending. Numerical analysis of the transient oscillations of the D-436-148FM engine mounted on the pylon of the AN-178 aircraft was performed. The amplitude-frequency response of oscillations is obtained in the frequency range below the fan speed in the cruising mode. The stability of engine oscillations at a resonant frequency close to the autorotation frequency has been studied. The results of the numerical simulation are presented in the form of diagrams. Orbits of the centers of gravity of the fan rotor and the motor casing in the resonant mode are constructed. Poincaré mappings of oscillations of the same points of the structure are also constructed.","PeriodicalId":418062,"journal":{"name":"Aerospace technic and technology","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134184129","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Результати експериментальних досліджень акустичних характеристик звукопоглинаючих конструкцій для ТРДД","authors":"Yevhen Rymarenko","doi":"10.32620/aktt.2023.4sup1.03","DOIUrl":"https://doi.org/10.32620/aktt.2023.4sup1.03","url":null,"abstract":"The subject of the research in this article is an acoustic liner designed to reduce aircraft noise in a wide frequency range. The purpose of the study is to determine the acoustic characteristics of an acoustic liner. Tasks: development of a theoretical model of the acoustic liner in the form of tubes of different lengths, calculation of the natural frequencies of each tube of the developed liner, determination of the frequency range in which sound absorption will occur, production of a test sample, and experimental determination of the sound absorption coefficient. An experimental setup is used to determine the sound absorption coefficient of the developed liner, which determines the acoustic characteristics of the acoustic liners using the standing wave method. This study presents the results of: calculation of the natural frequencies of the proposed liner, calculation of the dependence between the amplitude transmission coefficient and the frequency of the exciting force, and measurement of the acoustic characteristics of the proposed acoustic liner. The scientific and practical novelty of the obtained results is as follows: to solve the problem of noise absorption in a wide frequency range, a theoretical model of the acoustic liner, which should consist of tubes of different lengths, was developed. Each tube has its own frequency of oscillation of the air inside the tube. As the path of sound travel inside the tube increases, the natural frequency of the tube decreases. When tubes of different lengths are placed on the test sample, it is possible to obtain an acoustic liner with a significant number of natural frequencies, that is, noise will be absorbed in a wide frequency range. According to the calculation results, the proposed acoustic liner, consisting of seven types of tubes of different lengths, has more than 20 natural frequencies in the frequency range from 500 Hz to 4500 Hz, that is, the frequency range of absorption is quite wide. In order to verify the theoretical calculations with the help of a 3D printer, experimental samples of the proposed acoustic liner, as well as a real acoustic liner used to reduce the noise of the D-18T engine, were made and their experimental studies were carried out. The research results show that the proposed acoustic liner reduces noise in a wide frequency range. In the frequency range from 1300 Hz to 3500 Hz, the sound absorption coefficient exceeds 0.4, and in the range from 1500 Hz to 2600 Hz, the sound absorption coefficient is above 0.5. In the specified frequency ranges, the proposed acoustic liner has significant advantages over the D-18T acoustic liner. By reducing the cross-section of the tubes, or increasing the number of tubes of the experimental sample, it is possible to significantly increase the frequency range of sound absorption.","PeriodicalId":418062,"journal":{"name":"Aerospace technic and technology","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129384631","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Математичне моделювання пристінної оливної плівки в камері підшипника ГТД","authors":"Illia Petukhov, A. Kovalov","doi":"10.32620/aktt.2023.4sup2.05","DOIUrl":"https://doi.org/10.32620/aktt.2023.4sup2.05","url":null,"abstract":"The most preferable result of modeling the flow in the BC is the determination of the heat transfer coefficient to the inner wall. The complexity of solving this problem is due to both the complex geometry of the BC and the presence of a two-phase flow, the structure of which changes from air-droplet in the core to a nearly liquid in the wall oil film. Available research results show that even three-dimensional CFD modeling of such a flow does not completely solve the problem. At the same time, the calculation time is long, and the results require, at a minimum, selective experimental validation. At the same time, it can be considered proven that the main mechanism of heat transfer from the core to the wall region of the BC is related to the radial flow of droplets, and the thermal resistance of the wall oil film has a decisive effect on the value of the internal heat transfer coefficient. It is advisable to model these media on the basis of a two-dimensional problem with the averaging of phase parameters along the axis. Considering the small volume fraction of droplets, the Lagrangian approach can be used to model the two-phase flow in the core of the BC. This allows consideration of not only the polydispersity of the droplets, but also the creation and movement of secondary droplets during the formation of the wall oil film. One of the main problems in the modeling of the wall film is the definition of its flow regime and the corresponding criterion equations for calculating the coefficients of friction and heat transfer. Most of the equations use the longitudinal coordinate of the plate as a geometric parameter and cannot be applied to the bearing chamber. In this study, the possibility of converting the film flow into a flow similar to that occurring in a flat pipe is substantiated. This allows not only to consider the geometric features of the BC, but also to use the corresponding Reynolds numbers and similarity equations for the equivalent flow. Along with the use of a two-layer model for the boundary region and the concept of the analogy of transfer processes, this made it possible to form a mathematical model of the film, which considers all the components that determine the formation, movement, and heat transfer of the wall oil film. In addition, the model does not contain restrictions on the appearance of the parameters transverse profile, which are, for example, for the EWF model of the oil film in ANSYS FLUENT. The obtained results along with the previously developed air-droplet flow model in the core provide a complete two-dimensional model of the gas-liquid flow in the GTE bearing chamber, which allows the main geometric and all mode parameters to be used to determine the heat transfer coefficient to the inner wall of the chamber. Given the short calculation time, the proposed model allows for a detailed investigation of each factor’s contribution and element-by-element identification of the model based on the results of more detail","PeriodicalId":418062,"journal":{"name":"Aerospace technic and technology","volume":"2021 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116874891","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of the helicopter turboshafted engine regulator","authors":"Gennadii Ranchenko, Anna Buryachenko, Viacheslav Grudinkin, Dmitriy Burunov, V. Danilov","doi":"10.32620/aktt.2023.4sup1.07","DOIUrl":"https://doi.org/10.32620/aktt.2023.4sup1.07","url":null,"abstract":"The subject of research was the development of the RDC-450M-117V – the TV3-117VMA-SBM1V digital engine regulator – based on the RDC-450M previously created at the enterprise for the AI-450M engine, considering differences in engine characteristics and exploitation conditions. The work purpose was to develop RDC-450M-117V based on information about aircraft engine characteristics, including refinement of its mathematical model based on experimental data, taking into account the exploitation condition difference. The tasks faced by the developers were to determine the optimal regulator structure in view of exploitation conditions, refine the mathematical model of the engine, and study the characteristics of the pump-regulator, to select the optimal processing form for the signal of rotation sensors for torque measurement. The methods that were applied were experimental engine and pump-regulator characteristics study on the stands of JSC \"Element\", JSC \"Motor Sich\", and on pump-regulator manufacturer’s stands; processing of experimental data using numerical simulation with subsequent statistical analysis. The rotation sensors signals experimental data (waveforms) were studied using a quantitative analysis method. The results. Design and software documentation was developed considering the requirements of international standards DO-254 and DO-178C, and a prototype of the regulator new modification was made. The engine mathematical model was refined, on the basis of which the stand-imitator of aircraft engines was finalized for a new type of engine. An adaptive algorithm for controlling the pump-regulator was developed, which made it possible to ensure stable maintenance of fuel consumption, despite the unstable operation of the pump-regulator. Using a quantitative analysis of the torque sensor signal waveforms, characteristic points were found that ensure the choice of the optimal level of comparison (measurement). The pilot regulator prototype passed tests including electromagnetic compatibility and lightning resistance in specialized laboratories in Ukraine. The regulator was tested as part of the engine at the Motor Sich JSC stands and as part of a helicopter at the foreign customer site, including the first demonstration flight. The scientific novelty of the obtained results are: the clarified engine TV3-117VMA-SBM1V mathematical model was formed and implemented in a stand-imitator; the adaptive algorithm for controlling the pump-regulator was formed and allowed to provide stable fuel consumption maintenance, despite the pump-regulator unstable operation; and the optimal processing form for the signal of rotation sensors for measuring torque was selected. Practical significance. A new engine regulator was developed and tested, and it provided the first helicopter demonstration flight.  ","PeriodicalId":418062,"journal":{"name":"Aerospace technic and technology","volume":"88 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130298509","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Моделі дослідження стійкості високотехнологічних виробництв в сучасних політико-економічних умовах","authors":"Oleg Fedorovych, Oleg Slomchynskyi, Alina Yelizieva, Leonid Smidovych, Elena Yashina","doi":"10.32620/aktt.2023.4.12","DOIUrl":"https://doi.org/10.32620/aktt.2023.4.12","url":null,"abstract":"The task of studying the stability of high-tech enterprises (aviation, space, engineering industry) to the manifestation of threats and the occurrence of losses (economical, technological, etc.) is formed and solved. The relevance of this study is connected with the increasing risks that arise in the external environment and lead to the degradation of high-tech enterprises. The risks of functioning and development of high-tech enterprises connected with modern political and economic threats and the consequences of war are analyzed. It is concluded that the stability of high-tech production is one of the actual problems of restoring the country’s economy in the post- military period. Therefore, the topic of the proposed article is relevant, which explores possible ways to ensure the resilience of high-tech enterprises in the conditions of the turbulence of the world economy and the difficulties that arose as a result of the martial law of the country. An analysis of the direct security of the sustainability of high-tech enterprises in the post-military period is carried out. The possible expenses for the security and stability of the enterprise in the conditionals of the risks of causing possible threats (political and economic, climate, terrorist, military) are modeled. A model for the study of logistics processes, the formation of new supply chains of components, in the event of a delivery disruption, has been created. The expenses of restoring the supporting infrastructure of the enterprise because of the consequences of martial law and the aggressor’s actions are analyzed. The process of relocation (evacuation) of enterprises to new places is modeled as an example of ensuring the sustainability of enterprises during the war period. A simulation model is created to study the impact of threats and the emergence of expenses, to adopt preventive measures to ensure the sustainability of an enterprise. The scientific novelty of this study is connected with the development of a set of models that help to directly study the stability of high-tech enterprises to contemporary challenges and threats. The results of the research can be useful for modeling preventive action plans before the appearance of threats and expenses that improve the stability and reliability of the functioning of high-tech enterprises.","PeriodicalId":418062,"journal":{"name":"Aerospace technic and technology","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121666409","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Перспективи застосування електрохімічного полірування зразків скеффолд, виготовлених за адитивною технологією","authors":"Sergey Adjamskiy, G. Kononenko, Rostyslav Podolskyi, Sergey Baduk","doi":"10.32620/aktt.2023.4sup2.10","DOIUrl":"https://doi.org/10.32620/aktt.2023.4sup2.10","url":null,"abstract":"In recent years, the actual production of metal products directly from electronic data according to a three-dimensional model based on layer-by-layer manufacturing has evolved from rapid prototyping to additive manufacturing. As the quality of additively manufactured metal products continues to increase and their manufacturing processes improve and develop, the demand for additive manufacturing is increasing. Additive manufacturing technology, also known as 3D printing, has become increasingly popular recently. Using additive manufacturing, almost any complex geometry can be manufactured with high degree of precision. After the production of parts using the SLM technology from metal powder, post-processing is applied, in particular electrochemical polishing, the main purpose of which is to reduce surface roughness, increase the gloss of surface elements, and remove metal powder that has partially melted onto the outer surface of the product at the point of contact between the molten metal and the border of the part and the powder, which is located next to the melt. This is especially important for inclined surfaces, internal channels and cellular structures with developed outer surface. For research, samples were made using SLM technology from AISI 316L austenitic steel powder. The samples have a cube shape with a base of 10 mm, a height of 10 mm, and a thickness of 10 mm, with cell widths of 4 mm and 2 mm. The main body of both samples was printed using the same modes at a laser power of 220 W, a scanning speed of 1000 mm/s and a distance between laser passes of 0.14 mm. Samples were printed on Alfa-280 3D printer manufactured by ALT Ukraine LLC. Electropolishing was carried out in a solution of orthophosphoric acid (H3PO4) with glycerol (C3H8O3) by immersing the test samples in the electrolytic solution at a voltage of 17 V and a current density of 3 A/cm2. The control of weight and geometric parameters was carried out with the help of ADV-2000 analytical balances and MKC-25 micrometer. The electropolishing of the experimental samples took place in four stages: 1) visual - optical inspection with fixation, weight control before the start of the process; 2) electropolishing for 3 minutes, visual - optical inspection with photo fixation; weight control after 3 min. polishing process; 3) electropolishing of the same samples for another 3 minutes, visual – optical inspection with photo fixation, weight control after 6 minutes. polishing; 4) electropolishing of the same samples for another 3 minutes, visual - optical inspection with photo fixation; weight control after 9 min. electropolishing process. At each stage, a real current-voltage curve was recorded using an oscilloscope. As a result of weight control before and after the test, it was established that the samples lost approximately the same weight in the range of 6.9...7.1 % relative to the initial one. Based on the analysis of the obtained results, it was established that at a current densi","PeriodicalId":418062,"journal":{"name":"Aerospace technic and technology","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125377293","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Метрологічне забезпечення та автоматизація випробувань регулятора малорозмірного газотурбінного авіадвигуна","authors":"Anna Buryachenko, Dmitriy Burunov, Sergey Vialov","doi":"10.32620/aktt.2023.4.08","DOIUrl":"https://doi.org/10.32620/aktt.2023.4.08","url":null,"abstract":"The subject of this research was the possibility of creating a control and verification apparatus (CVA) for ensuring full-scale autonomous tests of the regulator of a small gas turbine aircraft engine developed at the enterprise. The purpose of this study was to develop CVA (a modern small-sized hardware and software complex that allows automating the performance tests, which is carried out as during the production technological cycle of the regulator, as well as in operation) based on information about the aircraft engine characteristics, including refinement of its mathematical model based on experimental data. The tasks faced by the developers were to determine the optimal set of functions of the equipment, which would provide sufficient data for a reliable assessment of the regulator's performance based on the test results while minimizing the time spent and the probability of errors, and the implementation of the function of automated performance of complete regulator measuring channels calibration, including the pressure measurement channel (together with the pressure sensor) and the fuel flow measurement channel (with the sensor of the angle of rotation of the dosing element of the fuel dispenser). The applied methods are follows: at the first stage of design it was the analysis of available data on the processes that need to be automated, after that the experimental method of research the first sample characteristics and its interaction with the aircraft engine was applied at the developer’s test base (JSC “Element”) and at engine test stands of JSC \"Motor Sich\", and then – a method of statistical data processing, including refinement of the mathematical model of the aircraft engine. The results. The developed CVA consists of a hardware part structurally designed in the form of a CVA block weighing 1.7 kg with built-in software and a software product installed on a personal computer. The mathematical model of the aircraft engine integrated into the built-in software allows you to perform a full-fledged check of the regulator's functioning, in particular, at the start of the engine, at the maintenance of the specified operating mode, while ensuring protection against exceeding the permissible values of the parameters. The scientific novelty of the obtained results is the development of the CVA with an integrated engine mathematical model and a set of functions that provide a full autonomous regulator operability check, which was verified in the process of testing on real engine. The practical significance of the obtained results lies in the fact that the production and operation of the newly developed aircraft engine regulator is equipped with a compact and easy-to-use means of full-fledged operational automated control of its performance.","PeriodicalId":418062,"journal":{"name":"Aerospace technic and technology","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129230451","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ефективність суднових енергетичних установок з теплообмінними апаратами з трубних пучків з лунковими системами","authors":"V. Kuznetsov, Anatolii Shevtsov","doi":"10.32620/aktt.2023.4sup2.02","DOIUrl":"https://doi.org/10.32620/aktt.2023.4sup2.02","url":null,"abstract":"The direction of increasing the efficiency of marine power plants by using heat exchange elements that implement intensive methods of heat transfer, which are characterized by a predominant increase in heat transfer over aerodynamic resistance, is considered. The research method is mathematical modeling of processes in power plants at the level of their individual elements – heat engine, power, and technological heat exchangers. The adequacy of the mathematical model for research the efficiency of power plants is justified by the results of verification and validation by comparing the results of calculations with the results of a physical experiment that have a discrepancy not exceeding 9.3 %. The goal of the research is to improve the economic, environmental, resource and weight-size parameters of power plants by using heat exchange elements with the intensification of the processes of convective transfer of heat and mass by using finned surfaces with dimples. Thanks to the performance of dimple systems on the edges of round pipes with spiral-ribbon finning and elliptical pipes with lamellar finning, it is possible to increase the heat transfer coefficient up to 36 %, while the resistance coefficient of the beam remains unchanged. The use of heat exchangers with the proposed heat transfer elements as part of ship power plants with low-speed engines and gas-and-steam turbine units allows to improve their economic and environmental characteristics. It was obtained that for tankers of the PANAMAX type, the increase in the efficiency of the ship's power plant is 1.3 % due to the use of elliptical surfaces with plate finning and hole systems on the ribs in the utilization boiler. The ship's EEDI index decreased by 1.7 %. For container ships with a deadweight of more than 100,000 tons, the change in these indexes was 2.5 and 2.7 %, respectively. For a marine gas-and-steam turbine plant, the efficiency increase was 2.4 %. The presented mathematical model of the power plant is characterized by positive results of approbation for constructive and verification calculations of power plants in marine energy, transport, and industry.","PeriodicalId":418062,"journal":{"name":"Aerospace technic and technology","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115033851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}