The subject of study in this article is the processes of controlling an unmanned aerial vehicle (UAV) of the quadcopter type. A quadcopter is a special case of a multicopter built according to the helicopter scheme, which has four main rotors. Such aircraft are widely used for many purposes, both civilian and military: from video recording of any phenomena to performing aerial reconnaissance of inaccessible territories, adjusting artillery weapons. The quadcopter belongs to the class of mechanical systems with low driveability, as the number of its drives (four propeller motors) is less than the number of degrees of freedom (six degrees). This is significantly different from the control of an aircraft-type UAV, where each degree of freedom is controlled by its own actuator. The low driveability of the quadcopter imposes its own peculiarities during its control. For example, the horizontal movement of the quadcopter in a given direction is accomplished by tilting the quadcopter in that direction by influencing certain propeller motors. Thus, when demanding the execution of the simplest movement of the device (movement along the linear X coordinate), at least three coordinates are controlled by the executive motors of the quadcopter: the formation of a lifting force to control the hovering of the UAV at a certain height, the change of the angle of inclination of the quadcopter according to the pitch angle, and the direct control of the movement speed of the quadcopter. Simultaneously, this influence induces the emergence of movement conditions along other coordinates. The research method involves constructing a mathematical model of a quadcopter based on the known equations of UAV motion. Several methods and algorithms of quadrocopter control are known, in this work, PID coordinate controllers are used. The Matlab Simulink dynamic simulation environment was used to build the mathematical model. In the process of studying the mutual influence in the process of controlling coordinates, the influence of controlling one coordinate in the static state of others (not necessarily at rest, but also in the state of movement) was revealed. Further, the mutual influence between the degrees of freedom during simultaneous control of at least two coordinates is considered (for example, control of pitch angle and yaw angle, height change with simultaneous braking along one of the linear coordinates). Conclusions. Studies have confirmed the existence of mutual influences, although in most cases such influence is manifested by a slight deterioration in the quality of transient processes along the adjustable coordinates. Only the change of the Euler angles when changing the height significantly worsens the quality of transient processes, which must be considered when designing control systems or recording algorithms of movement by coordinates.
{"title":"Дослідження взаємного впливу між каналами управління квадрокоптером за рахунок малої приводності БПЛА","authors":"Arkadii Zhukevych, Vitalii Dzhulgakov, Oleksandr Zhukevych","doi":"10.32620/aktt.2022.5.06","DOIUrl":"https://doi.org/10.32620/aktt.2022.5.06","url":null,"abstract":"The subject of study in this article is the processes of controlling an unmanned aerial vehicle (UAV) of the quadcopter type. A quadcopter is a special case of a multicopter built according to the helicopter scheme, which has four main rotors. Such aircraft are widely used for many purposes, both civilian and military: from video recording of any phenomena to performing aerial reconnaissance of inaccessible territories, adjusting artillery weapons. The quadcopter belongs to the class of mechanical systems with low driveability, as the number of its drives (four propeller motors) is less than the number of degrees of freedom (six degrees). This is significantly different from the control of an aircraft-type UAV, where each degree of freedom is controlled by its own actuator. The low driveability of the quadcopter imposes its own peculiarities during its control. For example, the horizontal movement of the quadcopter in a given direction is accomplished by tilting the quadcopter in that direction by influencing certain propeller motors. Thus, when demanding the execution of the simplest movement of the device (movement along the linear X coordinate), at least three coordinates are controlled by the executive motors of the quadcopter: the formation of a lifting force to control the hovering of the UAV at a certain height, the change of the angle of inclination of the quadcopter according to the pitch angle, and the direct control of the movement speed of the quadcopter. Simultaneously, this influence induces the emergence of movement conditions along other coordinates. The research method involves constructing a mathematical model of a quadcopter based on the known equations of UAV motion. Several methods and algorithms of quadrocopter control are known, in this work, PID coordinate controllers are used. The Matlab Simulink dynamic simulation environment was used to build the mathematical model. In the process of studying the mutual influence in the process of controlling coordinates, the influence of controlling one coordinate in the static state of others (not necessarily at rest, but also in the state of movement) was revealed. Further, the mutual influence between the degrees of freedom during simultaneous control of at least two coordinates is considered (for example, control of pitch angle and yaw angle, height change with simultaneous braking along one of the linear coordinates). Conclusions. Studies have confirmed the existence of mutual influences, although in most cases such influence is manifested by a slight deterioration in the quality of transient processes along the adjustable coordinates. Only the change of the Euler angles when changing the height significantly worsens the quality of transient processes, which must be considered when designing control systems or recording algorithms of movement by coordinates.","PeriodicalId":418062,"journal":{"name":"Aerospace technic and technology","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133972784","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}
The research subject is a digital twin of the process of filling the tank with gas mixture components. The aim is to justified choose the digital twin model of the tank filling process with a gas mixture. The task of the study consists of the analysis of construction methods and the operation modes of the digital twin as well as selecting the operation settings of the digital twin model, which ensure a rational reproduction of the gas-dynamic non-stationary of the tank filling process with a component of the gas mixture. The following results were obtained. In accordance with the digitalization concept of modern production, the need to build digital twins for individual physical and chemical processes is substantiated in relation to the researched thermal pulse processing technology. The specifics of the operation of the fuel mixture generator using the critical hole method are determined and the corresponding defining equations for the dosing of gas mixture components and the tank filling time are given for constructing a control system using a digital twin of the process. Existing methods of building digital twins similar to the system under study are analyzed. For further use in the structure of a digital twin of a separate tank filling subsystem, a component of the gas mixture, a finite-element model of gas-dynamic unsteady flow was built and a numerical study was conducted using the ANSYS Fluent software. The dependence on the tank filling time of such basic parameters of the process under study as pressure, temperature, and filled mass of the gas mixture was determined. Reasoned feasibility and developed reduced-order model (ROM model ANSYS Fluent) and used in ANSYS Twin Builder to build a digital twin. Developed and analyzed examples of digital twins of the system of filling the tank with a gas mixture using standard elements of the Twin Builder and Modelica libraries.
{"title":"Розробка цифрового близнюка наповнення резервуару газовою сумішшю","authors":"Vadim Garin, Denys Tkachenko, Olga Shypul, Sergiy Zaklinskyy, Oleg Tryfonov, Sergiy Plankovskyy","doi":"10.32620/aktt.2022.5.03","DOIUrl":"https://doi.org/10.32620/aktt.2022.5.03","url":null,"abstract":"The research subject is a digital twin of the process of filling the tank with gas mixture components. The aim is to justified choose the digital twin model of the tank filling process with a gas mixture. The task of the study consists of the analysis of construction methods and the operation modes of the digital twin as well as selecting the operation settings of the digital twin model, which ensure a rational reproduction of the gas-dynamic non-stationary of the tank filling process with a component of the gas mixture. The following results were obtained. In accordance with the digitalization concept of modern production, the need to build digital twins for individual physical and chemical processes is substantiated in relation to the researched thermal pulse processing technology. The specifics of the operation of the fuel mixture generator using the critical hole method are determined and the corresponding defining equations for the dosing of gas mixture components and the tank filling time are given for constructing a control system using a digital twin of the process. Existing methods of building digital twins similar to the system under study are analyzed. For further use in the structure of a digital twin of a separate tank filling subsystem, a component of the gas mixture, a finite-element model of gas-dynamic unsteady flow was built and a numerical study was conducted using the ANSYS Fluent software. The dependence on the tank filling time of such basic parameters of the process under study as pressure, temperature, and filled mass of the gas mixture was determined. Reasoned feasibility and developed reduced-order model (ROM model ANSYS Fluent) and used in ANSYS Twin Builder to build a digital twin. Developed and analyzed examples of digital twins of the system of filling the tank with a gas mixture using standard elements of the Twin Builder and Modelica libraries.","PeriodicalId":418062,"journal":{"name":"Aerospace technic and technology","volume":"121 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124170137","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}
The subject of study is the mathematical model for thermal processes during the formation of nanostructures in a plasma medium. In previous studies, it was shown that for the appearance of nanostructures, it is necessary that there be a certain temperature, its rate of increase, and thermal stresses. The required depth of the near-surface layer of the processed material, which is most favorable for the formation of nanostructures, is determined where the highest temperature stress gradients occur. The current work determines the technological parameters for obtaining nanostructures during ion-plasma treatment of the copper surface, as an example. The task of this work, by changing the energy of the ions, is to choose the location of the fields along the depth of the material to generate the necessary high temperature gradients in the given planes of the material. Thus, significant thermal stresses, and hence nanostructures, can be created in a large volume of material. The method used is analytical. In our work, a mathematical model was developed to describe the generation of temperature fields during ion-plasma surface treatment and tested on the process of copper treatment with oxygen ions. In this model, the joint actions of plasma flows and flows of charged particles with materials are realized through thermophysical, thermomechanical, thermal fatigue, diffusion, thermochemical, plasma-chemical processes and collisions. Therefore, the developed model will contribute to a more accurate determination of technological parameters for the formation of conditions conducive to the stable growth of nanostructures in the surface layers of processed materials. Because of numerous calculations, the dependence of the temperature of the surface layer of copper on the energy of oxygen ions was determined. The temperature fields in the zone of action of ions for three levels of the plane of the surface layer are calculated depending on the depth of penetration of ions for different times of interaction and at different current densities from 2.7∙106 to 2.1∙108 A/m2. Studies have shown that the maximum surface temperature is reached at the end of the thermal action of the ion. Conclusions. The obtained values of thermal stresses showed the possibility of formation of nanostructures in the surface layer of copper under the action of oxygen ions at a depth of x=0.5λm at a current density of 2.7∙106 A/m2. For the x=0.5λm plane at a current density of 3∙107 A/m2, where the largest temperature gradients were found, the maximum temperature stresses were calculated, amounting to 5∙108 N/m, which confirms the creation of conditions for obtaining nanostructures. But at 2.1∙108 A/m2, the total temperature rises, and the temperature gradients decrease, which decreases temperature stresses and failure to meet the conditions for obtaining nanostructures. The results obtained can be used to develop a technology for the production of nanostructures in a plasma environment,
研究的主题是等离子体介质中纳米结构形成过程的数学模型。以往的研究表明，纳米结构的形成需要一定的温度、温度的升高速率和热应力。加工材料的近表面层所需的深度是最有利于纳米结构形成的，这取决于温度应力梯度最高的地方。以铜表面离子等离子体处理为例，确定了获得纳米结构的工艺参数。这项工作的任务是，通过改变离子的能量，沿着材料的深度选择场的位置，以在材料的给定平面上产生必要的高温梯度。因此，可以在大量材料中产生显著的热应力和纳米结构。所使用的方法是分析的。在我们的工作中，建立了一个数学模型来描述离子等离子体表面处理过程中温度场的产生，并在氧离子处理铜的过程中进行了测试。该模型通过热物理、热机械、热疲劳、扩散、热化学、等离子体化学过程和碰撞实现等离子体流动和带电粒子随材料流动的联合作用。因此，所建立的模型将有助于更准确地确定工艺参数，以形成有利于纳米结构在加工材料表层稳定生长的条件。通过大量的计算，确定了铜表层温度对氧离子能量的依赖关系。在2.7∙106 ~ 2.1∙108 A/m2的不同电流密度下，根据离子在不同作用时间下的渗透深度，计算了离子在表面层平面三层作用区的温度场。研究表明，离子热作用结束时达到最高表面温度。结论。得到的热应力值表明，在2.7∙106 a /m2电流密度下，氧离子作用深度为x=0.5λm，铜的表层有可能形成纳米结构。在电流密度为3∙107 a /m2时，x=0.5λm平面的温度梯度最大，计算出的最大温度应力为5∙108 N/m，证实了获得纳米结构的条件已经具备。但在2.1∙108 A/m2时，总温度升高，温度梯度减小，温度应力减小，不满足获得纳米结构的条件。获得的结果可用于开发在等离子体环境中生产纳米结构的技术，例如，在氧环境中通过离子等离子体处理铜。在等离子体环境中，例如，在氧环境中对铜进行离子等离子体处理。
{"title":"Теоретичне дослідження температурних полів міді при формуванні наноструктурних шарів у плазмовому середовищі","authors":"Y. Shyrokyi, Andrey Sysoiev, Yuliia Panchenko","doi":"10.32620/aktt.2022.5.04","DOIUrl":"https://doi.org/10.32620/aktt.2022.5.04","url":null,"abstract":"The subject of study is the mathematical model for thermal processes during the formation of nanostructures in a plasma medium. In previous studies, it was shown that for the appearance of nanostructures, it is necessary that there be a certain temperature, its rate of increase, and thermal stresses. The required depth of the near-surface layer of the processed material, which is most favorable for the formation of nanostructures, is determined where the highest temperature stress gradients occur. The current work determines the technological parameters for obtaining nanostructures during ion-plasma treatment of the copper surface, as an example. The task of this work, by changing the energy of the ions, is to choose the location of the fields along the depth of the material to generate the necessary high temperature gradients in the given planes of the material. Thus, significant thermal stresses, and hence nanostructures, can be created in a large volume of material. The method used is analytical. In our work, a mathematical model was developed to describe the generation of temperature fields during ion-plasma surface treatment and tested on the process of copper treatment with oxygen ions. In this model, the joint actions of plasma flows and flows of charged particles with materials are realized through thermophysical, thermomechanical, thermal fatigue, diffusion, thermochemical, plasma-chemical processes and collisions. Therefore, the developed model will contribute to a more accurate determination of technological parameters for the formation of conditions conducive to the stable growth of nanostructures in the surface layers of processed materials. Because of numerous calculations, the dependence of the temperature of the surface layer of copper on the energy of oxygen ions was determined. The temperature fields in the zone of action of ions for three levels of the plane of the surface layer are calculated depending on the depth of penetration of ions for different times of interaction and at different current densities from 2.7∙106 to 2.1∙108 A/m2. Studies have shown that the maximum surface temperature is reached at the end of the thermal action of the ion. Conclusions. The obtained values of thermal stresses showed the possibility of formation of nanostructures in the surface layer of copper under the action of oxygen ions at a depth of x=0.5λm at a current density of 2.7∙106 A/m2. For the x=0.5λm plane at a current density of 3∙107 A/m2, where the largest temperature gradients were found, the maximum temperature stresses were calculated, amounting to 5∙108 N/m, which confirms the creation of conditions for obtaining nanostructures. But at 2.1∙108 A/m2, the total temperature rises, and the temperature gradients decrease, which decreases temperature stresses and failure to meet the conditions for obtaining nanostructures. The results obtained can be used to develop a technology for the production of nanostructures in a plasma environment,","PeriodicalId":418062,"journal":{"name":"Aerospace technic and technology","volume":"82 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132048771","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}
The subject matter of this article is the technological features analysis of the initial and repair of aircraft products painting. The goal is to analyze and systematize the trends in the global aircraft industry in the pneumatic painting technology field and the removal of old paintworks from the outer aircraft product surfaces. The tasks include analysis of directions for improving the pneumatic painting technology; analysis of laser removal technological features of old paintwork. The following results were obtained. The analysis of publications showed significant advantages of the electrostatic pneumatic painting system with limitations for composite materials. Relevant is the development of new paintwork materials with a reduced content of volatile organic compounds and an increased hiding power, as well as fundamentally new water-based paintwork systems. One of the modern means of technological equipment for pneumatic painting is an overhead crane-telescopic platform. The global trend is the creation of painting and service centres and robotization of paintwork. The laser removal technology of old paintwork is an effective innovative alternative to the methods of abrasive or chemical-mechanical cleaning from the outer aircraft product surfaces, which are currently used. The laser cleaning technology should provide the possibility of manual or automatic old paintwork removal from the double curvature surfaces, fastening elements, as well as the joints of the sheathing sheets without thermal damage to the anode film on the aluminium alloys’ sheathing. Laser stands and mobile laser platforms have high productivity and low labor intensity, multiple reductions in the disposing cost of the decomposition of old paintwork products, compliance with labor protection and environmental requirements compared to existing technologies. Conclusions. The scientific novelty of the materials presented in the article is shown by the analysis and systematization of the technological features of the aircraft products initial and repair painting; rationality substantiation for creating the painting and service centre for the Ukraine aviation industry; determination the directions of scientific and applied research on the laser removal technology of old multilayer paintwork.
{"title":"Аналіз технологічних особливостей початкового і ремонтного фарбування виробів авіаційної техніки","authors":"Yuri Dyachenko, Iryna Voronko, Oleksandr Gorlov","doi":"10.32620/aktt.2022.5.02","DOIUrl":"https://doi.org/10.32620/aktt.2022.5.02","url":null,"abstract":"The subject matter of this article is the technological features analysis of the initial and repair of aircraft products painting. The goal is to analyze and systematize the trends in the global aircraft industry in the pneumatic painting technology field and the removal of old paintworks from the outer aircraft product surfaces. The tasks include analysis of directions for improving the pneumatic painting technology; analysis of laser removal technological features of old paintwork. The following results were obtained. The analysis of publications showed significant advantages of the electrostatic pneumatic painting system with limitations for composite materials. Relevant is the development of new paintwork materials with a reduced content of volatile organic compounds and an increased hiding power, as well as fundamentally new water-based paintwork systems. One of the modern means of technological equipment for pneumatic painting is an overhead crane-telescopic platform. The global trend is the creation of painting and service centres and robotization of paintwork. The laser removal technology of old paintwork is an effective innovative alternative to the methods of abrasive or chemical-mechanical cleaning from the outer aircraft product surfaces, which are currently used. The laser cleaning technology should provide the possibility of manual or automatic old paintwork removal from the double curvature surfaces, fastening elements, as well as the joints of the sheathing sheets without thermal damage to the anode film on the aluminium alloys’ sheathing. Laser stands and mobile laser platforms have high productivity and low labor intensity, multiple reductions in the disposing cost of the decomposition of old paintwork products, compliance with labor protection and environmental requirements compared to existing technologies. Conclusions. The scientific novelty of the materials presented in the article is shown by the analysis and systematization of the technological features of the aircraft products initial and repair painting; rationality substantiation for creating the painting and service centre for the Ukraine aviation industry; determination the directions of scientific and applied research on the laser removal technology of old multilayer paintwork.","PeriodicalId":418062,"journal":{"name":"Aerospace technic and technology","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126448112","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}
Systems for ensuring the thermal regime of ground and space applications with a capacity of more than 6 kW are rationally built on the basis of heat transfer circuits with a two-phase coolant. In such circuits, heat is transferred from the devices to the coolant in the heat sink (thermoplate) by heat transfer by boiling. When the device is switched on and heated up, there is a transition from single-phase convection to developed boiling in the evaporator channel of the Heat sink, which is sometimes accompanied by significant overheating of the device and a temperature drop. When the device is turned off, the temperature decreases smoothly, without a drop. This undesirable phenomenon, called "thermal load hysteresis", or "Hysteresis Phenomena at the Onset of Nucleate boiling" can affect the reliability of the device, and is the subject of study in this article. The problem of hysteresis has been studied by many authors at the local level both during boiling in a large volume and during the flow of coolant in the channels. It is associated with the need for some overheating of the wall to start boiling, the origin of vaporization centers. This article reviews the studies on the problem of hysteresis and describes a task for the experimental study of the phenomenon of hysteresis in the evaporator channel of a heat sink during the transition from single-phase convection to boiling. Tasks: it is necessary to consider the factors affecting hysteresis and to develop and test a methodology for conducting the experiment on the stand of simulation of heat transfer circuits with a two-phase coolant at the integral level. According to the results of the review, it was found that hysteresis is affected by various factors such as the properties of the coolant, surface roughness, flow parameters, etc. Usually, the study of hysteresis is conducted out at the local level, but engineering practice is interested in the phenomenon at the integral level, and what is the probability and magnitude of overheating of the device when it is turned on. However, if hysteresis exists at the local level, it is not obvious that hysteresis will appear at the device level. The authors obtained a "boiling curve" of ammonia on an experimental heat sink with a characteristic temperature drop of the device and showed that the phenomenon of hysteresis exists at the integral level. Conclusions. Considering the probabilistic nature of the phenomenon, many factors affecting the hysteresis, including the design features of the thermoplate, the authors propose to perform further studies using the "integral" methodology on standard coolants, with parameters close to the operating conditions of standard thermal control systems.
{"title":"Явище гістерезису при тепловіддачі кипінням у двофазних контурах теплоперенесення","authors":"Gennady Gorbenko, Yevhen Rohovyi","doi":"10.32620/aktt.2022.5.01","DOIUrl":"https://doi.org/10.32620/aktt.2022.5.01","url":null,"abstract":"Systems for ensuring the thermal regime of ground and space applications with a capacity of more than 6 kW are rationally built on the basis of heat transfer circuits with a two-phase coolant. In such circuits, heat is transferred from the devices to the coolant in the heat sink (thermoplate) by heat transfer by boiling. When the device is switched on and heated up, there is a transition from single-phase convection to developed boiling in the evaporator channel of the Heat sink, which is sometimes accompanied by significant overheating of the device and a temperature drop. When the device is turned off, the temperature decreases smoothly, without a drop. This undesirable phenomenon, called \"thermal load hysteresis\", or \"Hysteresis Phenomena at the Onset of Nucleate boiling\" can affect the reliability of the device, and is the subject of study in this article. The problem of hysteresis has been studied by many authors at the local level both during boiling in a large volume and during the flow of coolant in the channels. It is associated with the need for some overheating of the wall to start boiling, the origin of vaporization centers. This article reviews the studies on the problem of hysteresis and describes a task for the experimental study of the phenomenon of hysteresis in the evaporator channel of a heat sink during the transition from single-phase convection to boiling. Tasks: it is necessary to consider the factors affecting hysteresis and to develop and test a methodology for conducting the experiment on the stand of simulation of heat transfer circuits with a two-phase coolant at the integral level. According to the results of the review, it was found that hysteresis is affected by various factors such as the properties of the coolant, surface roughness, flow parameters, etc. Usually, the study of hysteresis is conducted out at the local level, but engineering practice is interested in the phenomenon at the integral level, and what is the probability and magnitude of overheating of the device when it is turned on. However, if hysteresis exists at the local level, it is not obvious that hysteresis will appear at the device level. The authors obtained a \"boiling curve\" of ammonia on an experimental heat sink with a characteristic temperature drop of the device and showed that the phenomenon of hysteresis exists at the integral level. Conclusions. Considering the probabilistic nature of the phenomenon, many factors affecting the hysteresis, including the design features of the thermoplate, the authors propose to perform further studies using the \"integral\" methodology on standard coolants, with parameters close to the operating conditions of standard thermal control systems.","PeriodicalId":418062,"journal":{"name":"Aerospace technic and technology","volume":"74 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128155718","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}
Pub Date : 2022-08-22DOI: 10.32620/aktt.2022.4sup2.16
Tetiana Tykhomyrova, Olena Gordienko, Ruslan Bekhter, O. Podobnyj
This study describes the results of studying the effect of modification/micro alloying with hafnium and alloying with tantalum on the morphology and distribution of the carbide phase in the ZhS3DK-VI alloy microstructure. The carbide phase is an integral structural component of the microstructure of nickel heat-resistant alloys, has a tremendous impact on the strength characteristics of the material. In this regard, the shape, size, and distribution of particles of this phase in the microstructure are of great importance. The formation of the morphology of carbide particles largely depends on the technological factors of casting such as temperature of the ceramic mold, crystallization rate, melt temperature, etc. The higher the temperature parameters and the lower the crystallization rate during casting, the coarser the morphology and topography of carbide particles formed during solidification and, accordingly, the lower the strength characteristics of the material. However, technological parameters also affect the geometry of the casting and it is not always possible to change the technology; so the only possibility is the use of modification or alloying of the alloy upon receipt of the work piece. Such carbide-forming elements as hafnium and tantalum, due to their chemical activity, react with carbon at the stage of crystallization and form thermally stable primary MC-type carbides. The use of hafnium in nickel alloys is limited to a concentration of 0.1 % since at a higher concentration, this element and nickel form a eutectic phase, the melting temperature of which is much lower than the homogenization temperature of the alloys. It is studied the possibility of doping the ZhS3DK-VI alloy with tantalum to form a favorable morphology of the carbide phase. The dispersed carbide particles are taken in the microstructure of the ZhS3DK-VI alloy after experimental work. The chemical composition of the particles is dominated by tantalum, and there is some hafnium.
{"title":"Морфологія і топографія карбідної фази при легуванні сплава ЖС3ДК-ВІ гафнієм і танталом","authors":"Tetiana Tykhomyrova, Olena Gordienko, Ruslan Bekhter, O. Podobnyj","doi":"10.32620/aktt.2022.4sup2.16","DOIUrl":"https://doi.org/10.32620/aktt.2022.4sup2.16","url":null,"abstract":"This study describes the results of studying the effect of modification/micro alloying with hafnium and alloying with tantalum on the morphology and distribution of the carbide phase in the ZhS3DK-VI alloy microstructure. The carbide phase is an integral structural component of the microstructure of nickel heat-resistant alloys, has a tremendous impact on the strength characteristics of the material. In this regard, the shape, size, and distribution of particles of this phase in the microstructure are of great importance. The formation of the morphology of carbide particles largely depends on the technological factors of casting such as temperature of the ceramic mold, crystallization rate, melt temperature, etc. The higher the temperature parameters and the lower the crystallization rate during casting, the coarser the morphology and topography of carbide particles formed during solidification and, accordingly, the lower the strength characteristics of the material. However, technological parameters also affect the geometry of the casting and it is not always possible to change the technology; so the only possibility is the use of modification or alloying of the alloy upon receipt of the work piece. Such carbide-forming elements as hafnium and tantalum, due to their chemical activity, react with carbon at the stage of crystallization and form thermally stable primary MC-type carbides. The use of hafnium in nickel alloys is limited to a concentration of 0.1 % since at a higher concentration, this element and nickel form a eutectic phase, the melting temperature of which is much lower than the homogenization temperature of the alloys. It is studied the possibility of doping the ZhS3DK-VI alloy with tantalum to form a favorable morphology of the carbide phase. The dispersed carbide particles are taken in the microstructure of the ZhS3DK-VI alloy after experimental work. The chemical composition of the particles is dominated by tantalum, and there is some hafnium.","PeriodicalId":418062,"journal":{"name":"Aerospace technic and technology","volume":"436 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114256410","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}
Pub Date : 2022-08-22DOI: 10.32620/aktt.2022.4sup1.15
A. Sanin, Igor Mamchur, S. Mamchur
Diffusion welding is the ideal solution for joining dissimilar materials. This method is particularly effective if you should get a strong monolithic joint without the formation of a rough weld or solder seam. It is used if it is impossible to use standard fasteners. The main scope of this type of welding is the area of high technologies - aviation, space and other types of heavy engineering. All the advantages make the process indispensable under certain conditions and classify it as a high-tech type. This paper considers compounds of dissimilar metals nickel-niobium. In connection with the formation of many intermetallic compounds between these metals, the technology of diffusion welding in a vacuum was chosen. This method allows you to connect materials without melting due to the mutual diffusion of the components. The welding parameters affect the phase formation of the diffusion zone. To study the phase composition, a method of microstructural, X-ray microanalysis, as well as a state diagram of nickel-niobium, is proposed. When studying the weldability of the nickel-niobium system, samples were made in the form of a cube with a side of 10 mm, which was clamped in a mandrel and filled with Wood's alloy. The samples were not subjected to digestion, since during the polishing process, due to the different hardness of the phases, the structure turned out to be thermal polishing. The proposed scheme made it possible to study in detail the phase composition of individual layers of the diffusion zone, their dimensions and dependence on welding parameters. According to the results of quantitative X-ray microanalysis, we did not obtain accurate data on the phase composition and extent of diffuse layers. Qualitative X-ray spectral microanalysis, which was carried out by continuous scanning with an electron probe through the diffuse zone, made it possible to fix the phase reflections on the concentration curves and to determine the extent of the diffusion layers. For a more visual representation of the arrangement of the phases, a combined nickel-niobium diagram with a concentration curve is considered. The studies carried out made it possible to obtain a high-quality joint with mechanical properties that ensure reliability under operating conditions.
{"title":"Дослідження фазоутворення після дифузійного зварювання у вакуумі з’єднання нікель-ніобій","authors":"A. Sanin, Igor Mamchur, S. Mamchur","doi":"10.32620/aktt.2022.4sup1.15","DOIUrl":"https://doi.org/10.32620/aktt.2022.4sup1.15","url":null,"abstract":"Diffusion welding is the ideal solution for joining dissimilar materials. This method is particularly effective if you should get a strong monolithic joint without the formation of a rough weld or solder seam. It is used if it is impossible to use standard fasteners. The main scope of this type of welding is the area of high technologies - aviation, space and other types of heavy engineering. All the advantages make the process indispensable under certain conditions and classify it as a high-tech type. This paper considers compounds of dissimilar metals nickel-niobium. In connection with the formation of many intermetallic compounds between these metals, the technology of diffusion welding in a vacuum was chosen. This method allows you to connect materials without melting due to the mutual diffusion of the components. The welding parameters affect the phase formation of the diffusion zone. To study the phase composition, a method of microstructural, X-ray microanalysis, as well as a state diagram of nickel-niobium, is proposed. When studying the weldability of the nickel-niobium system, samples were made in the form of a cube with a side of 10 mm, which was clamped in a mandrel and filled with Wood's alloy. The samples were not subjected to digestion, since during the polishing process, due to the different hardness of the phases, the structure turned out to be thermal polishing. The proposed scheme made it possible to study in detail the phase composition of individual layers of the diffusion zone, their dimensions and dependence on welding parameters. According to the results of quantitative X-ray microanalysis, we did not obtain accurate data on the phase composition and extent of diffuse layers. Qualitative X-ray spectral microanalysis, which was carried out by continuous scanning with an electron probe through the diffuse zone, made it possible to fix the phase reflections on the concentration curves and to determine the extent of the diffusion layers. For a more visual representation of the arrangement of the phases, a combined nickel-niobium diagram with a concentration curve is considered. The studies carried out made it possible to obtain a high-quality joint with mechanical properties that ensure reliability under operating conditions.","PeriodicalId":418062,"journal":{"name":"Aerospace technic and technology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129286043","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}
Pub Date : 2022-08-22DOI: 10.32620/aktt.2022.4sup2.09
Volodymyr Nazin
The design of reliable rotor supports for modern high-speed machines is associated with the solution of many complex problems, both theoretical and experimental. Experimental studies play an important role in the system of scientific research and allow improvement and refine mathematical models and the application of numerical methods for their implementation. Experimental studies are usually selective and therefore require careful preparation. The task was set to investigate the characteristics of a hydrostatic bearing in the starting and braking modes. A program of experimental studies of the behavior of a shaft on hydrostatic bearings for the most difficult operating conditions has been developed. The advantages of hydrostatic bearings are given compared with other types of plain bearings, as well as compared with rolling bearings. The effectiveness of hydrostatic bearings is shown, compared with other types of bearings, for modern high-speed machines, in which there is an increase in vibration overloads and vibration displacements. Hydrostatic bearings have proven themselves in all operating modes, including transient ones. A description of the experimental setup for the study of transient modes of operation of the shaft on hydrostatic bearings is given. Studies of the transient modes of operation of the shaft on hydrostatic bearings were conducted at various values of the pressure of the working fluid supply, residual unbalance, as well as various values of the diameter of the hydrostatic bearing. To identify the movement of the rotor on hydrostatic bearings, the values of the amplitudes of oscillations during stationary (steady) movement of the rotor are also presented. It is shown that the comparison of the oscillation amplitudes of the rotor on hydrostatic bearings with a diameter of 0.06 m for the cases of non-stationary and stationary modes of its operation during the acceleration of the amplitude of oscillations in the entire range of rotational speeds is slightly lower (by about 15…20 %) than in the case of a stationary mode of operation of the rotor. When the rotor slows down, the amplitude of the rotor oscillations at high speeds is somewhat larger (by about 7…9 %), and at low speeds it is less by 8…10 % than in the case of a stationary rotor operation. The small influence of the non-stationary nature of the rotor movement on the dynamic characteristics can be explained by its large mass.
{"title":"Аналіз роботи гідростатичного підшипника на перехідних режимах","authors":"Volodymyr Nazin","doi":"10.32620/aktt.2022.4sup2.09","DOIUrl":"https://doi.org/10.32620/aktt.2022.4sup2.09","url":null,"abstract":"The design of reliable rotor supports for modern high-speed machines is associated with the solution of many complex problems, both theoretical and experimental. Experimental studies play an important role in the system of scientific research and allow improvement and refine mathematical models and the application of numerical methods for their implementation. Experimental studies are usually selective and therefore require careful preparation. The task was set to investigate the characteristics of a hydrostatic bearing in the starting and braking modes. A program of experimental studies of the behavior of a shaft on hydrostatic bearings for the most difficult operating conditions has been developed. The advantages of hydrostatic bearings are given compared with other types of plain bearings, as well as compared with rolling bearings. The effectiveness of hydrostatic bearings is shown, compared with other types of bearings, for modern high-speed machines, in which there is an increase in vibration overloads and vibration displacements. Hydrostatic bearings have proven themselves in all operating modes, including transient ones. A description of the experimental setup for the study of transient modes of operation of the shaft on hydrostatic bearings is given. Studies of the transient modes of operation of the shaft on hydrostatic bearings were conducted at various values of the pressure of the working fluid supply, residual unbalance, as well as various values of the diameter of the hydrostatic bearing. To identify the movement of the rotor on hydrostatic bearings, the values of the amplitudes of oscillations during stationary (steady) movement of the rotor are also presented. It is shown that the comparison of the oscillation amplitudes of the rotor on hydrostatic bearings with a diameter of 0.06 m for the cases of non-stationary and stationary modes of its operation during the acceleration of the amplitude of oscillations in the entire range of rotational speeds is slightly lower (by about 15…20 %) than in the case of a stationary mode of operation of the rotor. When the rotor slows down, the amplitude of the rotor oscillations at high speeds is somewhat larger (by about 7…9 %), and at low speeds it is less by 8…10 % than in the case of a stationary rotor operation. The small influence of the non-stationary nature of the rotor movement on the dynamic characteristics can be explained by its large mass.","PeriodicalId":418062,"journal":{"name":"Aerospace technic and technology","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121289402","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}
Pub Date : 2022-08-22DOI: 10.32620/aktt.2022.4sup2.17
Natalіja Kalіnіna, Diana Glushkova, N. Tsokur, T. Nosova, Valerij Bagrov, S. Demchenko
The substantiation of the scandium selection for microalloying and modifying of high-strength aluminum alloys. The research material is a high-strength aluminum alloy B96C1 of the Al-Zn-Mg-Cu system. Scandium was chosen as a microalloy and modifying element. The state diagram of Al-Sc, physical, and mechanical properties of scandium have been studied. Modes of heat treatment of B96C1 alloy with 0.3 % scandium have been developed. The structure and mechanical properties of the modified alloy were studied. The conducted complex of studies confirmed the microleveling and modifying the action of scandium in Al-melt, the technology of the introduction of scandium into melt-melt was developed, the amount of Sc was optimized. AlSc alloys have a significant effect on artificial aging. The study of the kinetics of the decomposition process showed the supersaturation of the solid solution obtained by crystallization. During the decomposition of a solid solution of scandium in aluminum, particles of the stable phase of Al3Sc are released. Based on the analysis of the Al-Sc state diagram, the homogenization temperatures of hardening and aging of the aluminum alloy B96Ts1 with optimization of the cooling rate of the workpieces were selected. In the modified blanks, grain grinding was achieved 2.5 times and the characteristics of the yield strength and yield strength of the alloy while maintaining plasticity. For aluminum alloy B96Ts1, the choice of scandium as a microalloying and modifying element is justified in terms of compliance with its physicochemical nature and properties of aluminum-based alloys. Because of hardening the alloys of the Al-Sc system, there is no decomposition of the solid solution with the release of Al3Sc intermetallic particles, which is a scientific novelty. The main effect of scandium is to increase the strength properties due to the formation of dispersed decomposition products of a solid solution of scandium in aluminum and preservation in heat-treated semi-finished products of stable structure with small subgrains. The establishment of the technology of the introduction of scan-action into the melt and temperature-time parameters of heat treatment of workpieces allowed to obtain a dispersed structure and a high set of mechanical properties of the alloy B96Ts1, which is the practical value of the work.
{"title":"Обґрунтування вибору скандію для мікролегування високоміцних алюмінієвих сплавів","authors":"Natalіja Kalіnіna, Diana Glushkova, N. Tsokur, T. Nosova, Valerij Bagrov, S. Demchenko","doi":"10.32620/aktt.2022.4sup2.17","DOIUrl":"https://doi.org/10.32620/aktt.2022.4sup2.17","url":null,"abstract":"The substantiation of the scandium selection for microalloying and modifying of high-strength aluminum alloys. The research material is a high-strength aluminum alloy B96C1 of the Al-Zn-Mg-Cu system. Scandium was chosen as a microalloy and modifying element. The state diagram of Al-Sc, physical, and mechanical properties of scandium have been studied. Modes of heat treatment of B96C1 alloy with 0.3 % scandium have been developed. The structure and mechanical properties of the modified alloy were studied. The conducted complex of studies confirmed the microleveling and modifying the action of scandium in Al-melt, the technology of the introduction of scandium into melt-melt was developed, the amount of Sc was optimized. AlSc alloys have a significant effect on artificial aging. The study of the kinetics of the decomposition process showed the supersaturation of the solid solution obtained by crystallization. During the decomposition of a solid solution of scandium in aluminum, particles of the stable phase of Al3Sc are released. Based on the analysis of the Al-Sc state diagram, the homogenization temperatures of hardening and aging of the aluminum alloy B96Ts1 with optimization of the cooling rate of the workpieces were selected. In the modified blanks, grain grinding was achieved 2.5 times and the characteristics of the yield strength and yield strength of the alloy while maintaining plasticity. For aluminum alloy B96Ts1, the choice of scandium as a microalloying and modifying element is justified in terms of compliance with its physicochemical nature and properties of aluminum-based alloys. Because of hardening the alloys of the Al-Sc system, there is no decomposition of the solid solution with the release of Al3Sc intermetallic particles, which is a scientific novelty. The main effect of scandium is to increase the strength properties due to the formation of dispersed decomposition products of a solid solution of scandium in aluminum and preservation in heat-treated semi-finished products of stable structure with small subgrains. The establishment of the technology of the introduction of scan-action into the melt and temperature-time parameters of heat treatment of workpieces allowed to obtain a dispersed structure and a high set of mechanical properties of the alloy B96Ts1, which is the practical value of the work.","PeriodicalId":418062,"journal":{"name":"Aerospace technic and technology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130703560","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}
When creating a modern aircraft, the principle of optimal integration of the power plant and the aircraft is used to ensure the maximum target function, determined by its functional purpose. The specific fuel consumption and specific thrust of the power plant depend significantly on the loss of the total air pressure in the inlet device, which is characterized by the total recovery factor. The change in pressure along the diameter of the propfan affects the efficiency of the inlet of the power plant. When using the inlet ring device, its efficiency decreases, due to low pressure in the area of the root part of the propfan blades. The use of a bucket inlet allows air to be supplied to the channel from the area located near the middle part of the blade height and this is the main factor influencing the reduction of pressure losses in the air supply channel. When using a bucket inlet, curvature and constriction are important factors influencing the effectiveness of S-channels. The influence of the curvature of the S-shaped channel on the total pressure recovery coefficient at a constant value of its narrowing is studied in this work. The study S-shaped channel in its geometric parameters is equivalent to the channel of the annular inlet device of a power plant with a turbofan engine. The total pressure recovery coefficient of an S-shaped channel is calculated from the flow parameters in the sections of the S-shaped channel by solving the Navier-Stokes equations using the Florian Menter two-layer turbulence model (SST Transitional No. 4 Gamma Theta) and the combined finite element model at the entrance to the channel and in the channel itself - hexahedral, at the exit tetrahedral. An analysis of the dependence of the total pressure recovery coefficient of the S-shaped channel on the M number and the channel curvature shows that, up to a curvature of 0.002, the total pressure recovery coefficient is not significantly affected. A further increase in the channel curvature has a significant effect on the change in the total pressure recovery coefficient, which is associated with flow separation and losses from the vortex formation.
{"title":"Аналіз впливу кривизни S-подібного каналу та умов польоту на ефективність ковшового вхідного пристрою","authors":"Oleg Zhornik, Ihor Kravchenko, Mykhailo Mitrakhovych, Ekaterina Balalaieva","doi":"10.32620/aktt.2022.4sup2.04","DOIUrl":"https://doi.org/10.32620/aktt.2022.4sup2.04","url":null,"abstract":"When creating a modern aircraft, the principle of optimal integration of the power plant and the aircraft is used to ensure the maximum target function, determined by its functional purpose. The specific fuel consumption and specific thrust of the power plant depend significantly on the loss of the total air pressure in the inlet device, which is characterized by the total recovery factor. The change in pressure along the diameter of the propfan affects the efficiency of the inlet of the power plant. When using the inlet ring device, its efficiency decreases, due to low pressure in the area of the root part of the propfan blades. The use of a bucket inlet allows air to be supplied to the channel from the area located near the middle part of the blade height and this is the main factor influencing the reduction of pressure losses in the air supply channel. When using a bucket inlet, curvature and constriction are important factors influencing the effectiveness of S-channels. The influence of the curvature of the S-shaped channel on the total pressure recovery coefficient at a constant value of its narrowing is studied in this work. The study S-shaped channel in its geometric parameters is equivalent to the channel of the annular inlet device of a power plant with a turbofan engine. The total pressure recovery coefficient of an S-shaped channel is calculated from the flow parameters in the sections of the S-shaped channel by solving the Navier-Stokes equations using the Florian Menter two-layer turbulence model (SST Transitional No. 4 Gamma Theta) and the combined finite element model at the entrance to the channel and in the channel itself - hexahedral, at the exit tetrahedral. An analysis of the dependence of the total pressure recovery coefficient of the S-shaped channel on the M number and the channel curvature shows that, up to a curvature of 0.002, the total pressure recovery coefficient is not significantly affected. A further increase in the channel curvature has a significant effect on the change in the total pressure recovery coefficient, which is associated with flow separation and losses from the vortex formation.","PeriodicalId":418062,"journal":{"name":"Aerospace technic and technology","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131414514","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}
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