Pub Date : 2022-11-18DOI: 10.18287/2541-7533-2022-21-3-7-22
P. V. Vasin, E. Barinova
In this paper, we solve the problem of experimental determination of the accuracy of a device for measuring mass-centering and inertial characteristics of nanosatellites which was developed at Samara University and based on the principle of inverted torsional pendulum. A procedure for determining the measurement error of the inertia tensor components and the center-of-mass coordinates using reference objects is proposed. For this purpose, a reference composite object of variable configuration was developed and produced in the form of a CubeSat 3U nanosatellite. With the help of this standard, a modified method of conducting an experiment was developed, which allows reducing the influence of errors in the manufacture of the device and its tooling on the measurement accuracy by averaging the homogeneous quantities. The article presents the results of a series of experiments to determine the errors in measuring mass-centering and inertial characteristics of a reference composite object of three variants of assembly. This series of experiments confirmed the measurement error theoretically calculated and stated in the technical documentation for the device. In addition, the accuracy of the electronic optical sensor installed on the device was evaluated and it was found that the influence of environmental factors on its operation is insignificant and can be neglected. The results of this work can be used to determine the error of measuring the center-of-mass coordinates and the inertia tensor components of a CubeSat 1U-3U nanosatellite at the pre-launch testing stage.
{"title":"Procedure of assessing the error of the device for measuring mass-centering and inertial characteristics of nanosatellites using reference objects","authors":"P. V. Vasin, E. Barinova","doi":"10.18287/2541-7533-2022-21-3-7-22","DOIUrl":"https://doi.org/10.18287/2541-7533-2022-21-3-7-22","url":null,"abstract":"In this paper, we solve the problem of experimental determination of the accuracy of a device for measuring mass-centering and inertial characteristics of nanosatellites which was developed at Samara University and based on the principle of inverted torsional pendulum. A procedure for determining the measurement error of the inertia tensor components and the center-of-mass coordinates using reference objects is proposed. For this purpose, a reference composite object of variable configuration was developed and produced in the form of a CubeSat 3U nanosatellite. With the help of this standard, a modified method of conducting an experiment was developed, which allows reducing the influence of errors in the manufacture of the device and its tooling on the measurement accuracy by averaging the homogeneous quantities. The article presents the results of a series of experiments to determine the errors in measuring mass-centering and inertial characteristics of a reference composite object of three variants of assembly. This series of experiments confirmed the measurement error theoretically calculated and stated in the technical documentation for the device. In addition, the accuracy of the electronic optical sensor installed on the device was evaluated and it was found that the influence of environmental factors on its operation is insignificant and can be neglected. The results of this work can be used to determine the error of measuring the center-of-mass coordinates and the inertia tensor components of a CubeSat 1U-3U nanosatellite at the pre-launch testing stage.","PeriodicalId":265584,"journal":{"name":"VESTNIK of Samara University. Aerospace and Mechanical Engineering","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132101798","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 : 2022-11-18DOI: 10.18287/2541-7533-2022-21-3-127-140
A. Ryabov, K. Y. Mokhov, O. Voronkov, A. Kudryavtsev, A. A. Museev
The article presents theoretical basis for the industry-based approach for finite element modeling of stable crack growth in the main parts of an aviation gas turbine engine. An axial compressor disc is used as an example. Parameters of typical FE-models applied are provided. In addition, some effective practices of FE-modeling representing the novelty of this work are described: crack evolution increment under-relaxation and automation of the process of constructing a new crack front. Some simulation results are presented demonstrating implementation of the approach steps and benefits gained from the application of the listed features. Under-relaxation ensures maintaining the stability of a numerical solution for a significantly larger crack increment size. This leads to essential effort decrease as a result of reducing the total number of simulation cycles required. Automatic construction of a new crack front allows significant improvement in crack representation accuracy during the simulation process due to the greater number of points for which crack front evolution is determined.
{"title":"Aspects of simulating stable low-cycle fatigue crack growth in the main parts of aircraft gas turbine engines","authors":"A. Ryabov, K. Y. Mokhov, O. Voronkov, A. Kudryavtsev, A. A. Museev","doi":"10.18287/2541-7533-2022-21-3-127-140","DOIUrl":"https://doi.org/10.18287/2541-7533-2022-21-3-127-140","url":null,"abstract":"The article presents theoretical basis for the industry-based approach for finite element modeling of stable crack growth in the main parts of an aviation gas turbine engine. An axial compressor disc is used as an example. Parameters of typical FE-models applied are provided. In addition, some effective practices of FE-modeling representing the novelty of this work are described: crack evolution increment under-relaxation and automation of the process of constructing a new crack front. Some simulation results are presented demonstrating implementation of the approach steps and benefits gained from the application of the listed features. Under-relaxation ensures maintaining the stability of a numerical solution for a significantly larger crack increment size. This leads to essential effort decrease as a result of reducing the total number of simulation cycles required. Automatic construction of a new crack front allows significant improvement in crack representation accuracy during the simulation process due to the greater number of points for which crack front evolution is determined.","PeriodicalId":265584,"journal":{"name":"VESTNIK of Samara University. Aerospace and Mechanical Engineering","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131339375","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 : 2022-11-18DOI: 10.18287/2541-7533-2022-21-3-69-84
Shumin Chen, Y. Zabolotnov
The problem of forming a rotating ring-shaped tethered system consisting of three nanosatellites is considered. To analyze the dynamics of the tether system, a mathematical model is developed in the orbital coordinate system using the Lagrange method. Using the sliding mode control method, two control programs for the deployment of tethers are proposed, in which tether tensions and thrust forces created by low-thrust engines are used as controls. In the first control program, the control actions are directly limited by the permissible limits of tether tensions forces and thrust forces, and when designing the second control program, an auxiliary dynamic system is added into the control system, which introduces control corrections that take into account the saturation effect. The stability of motion of the tethered formation system for both control programs is investigated using the Lyapunov theory. The results of numerical simulations confirmed the possibility of using the proposed control programs for the formation of a rotating triangular tethered system in the form of a regular triangle in the presence of disturbances and with account of the given constraints.
{"title":"Formation of a rotating ring-shaped three-body tethered nanosatellite system with limited control","authors":"Shumin Chen, Y. Zabolotnov","doi":"10.18287/2541-7533-2022-21-3-69-84","DOIUrl":"https://doi.org/10.18287/2541-7533-2022-21-3-69-84","url":null,"abstract":"The problem of forming a rotating ring-shaped tethered system consisting of three nanosatellites is considered. To analyze the dynamics of the tether system, a mathematical model is developed in the orbital coordinate system using the Lagrange method. Using the sliding mode control method, two control programs for the deployment of tethers are proposed, in which tether tensions and thrust forces created by low-thrust engines are used as controls. In the first control program, the control actions are directly limited by the permissible limits of tether tensions forces and thrust forces, and when designing the second control program, an auxiliary dynamic system is added into the control system, which introduces control corrections that take into account the saturation effect. The stability of motion of the tethered formation system for both control programs is investigated using the Lyapunov theory. The results of numerical simulations confirmed the possibility of using the proposed control programs for the formation of a rotating triangular tethered system in the form of a regular triangle in the presence of disturbances and with account of the given constraints.","PeriodicalId":265584,"journal":{"name":"VESTNIK of Samara University. Aerospace and Mechanical Engineering","volume":"115 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132211361","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 : 2022-11-18DOI: 10.18287/2541-7533-2022-21-3-96-107
I. Kolesnikov, P. Koropets, D. Manturov, Ye. V. Shakhmatov
As the science of friction developed, tribologists showed that reliable operation of friction units is determined by the wear resistance of the surface layer, its ability to adapt to changing operating conditions. In this regard, there is a need not only to create structures on the surfaces of friction units that have the properties of self-regulation and self-organization, but also to monitor changes in the characteristics of the surface layer. This article presents an innovative methodology for monitoring the life cycle of surface layers coated by vacuum ion-plasma treatment. In this paper, we propose a dynamic model based on the hypothesis that roughness is both a factor that excites mechanical vibrations and a consequence of these vibrations, whereas roughness changes as a result of wear under the influence of local dynamic forces. It is shown that a friction pair is a nonlinear system with complex feedbacks. Its stationary motion can be considered as a strange attractor. The randomness of motion in the vicinity of the limit cycle is due to the presence of a link of constant delay with rigid positive feedback in the model. As a result, there is constant reconfiguration of the amplitude and phase of the oscillations.
{"title":"Mathematical modeling of the evolution of a tribosystem in the process of formation of equilibrium roughness of a frictional contact","authors":"I. Kolesnikov, P. Koropets, D. Manturov, Ye. V. Shakhmatov","doi":"10.18287/2541-7533-2022-21-3-96-107","DOIUrl":"https://doi.org/10.18287/2541-7533-2022-21-3-96-107","url":null,"abstract":"As the science of friction developed, tribologists showed that reliable operation of friction units is determined by the wear resistance of the surface layer, its ability to adapt to changing operating conditions. In this regard, there is a need not only to create structures on the surfaces of friction units that have the properties of self-regulation and self-organization, but also to monitor changes in the characteristics of the surface layer. This article presents an innovative methodology for monitoring the life cycle of surface layers coated by vacuum ion-plasma treatment. In this paper, we propose a dynamic model based on the hypothesis that roughness is both a factor that excites mechanical vibrations and a consequence of these vibrations, whereas roughness changes as a result of wear under the influence of local dynamic forces. It is shown that a friction pair is a nonlinear system with complex feedbacks. Its stationary motion can be considered as a strange attractor. The randomness of motion in the vicinity of the limit cycle is due to the presence of a link of constant delay with rigid positive feedback in the model. As a result, there is constant reconfiguration of the amplitude and phase of the oscillations.","PeriodicalId":265584,"journal":{"name":"VESTNIK of Samara University. Aerospace and Mechanical Engineering","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121954988","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 : 2022-11-18DOI: 10.18287/2541-7533-2022-21-3-23-35
Yu. V. Zinenkov, A. Lukovnikov, S. Agaverdyev
The article describes the solution of a complex problem to determine the optimal parameters and engine layout for the power plant of an advanced unmanned aerial vehicle according to the methodology developed by the authors using the authors complex mathematical model and the well-known method of indirect statistical optimization based on self-organization. At the same time, the main aerodynamic and flight performance characteristics of the unmanned aerial vehicle under study, calculated according to engineering methods, are shown, as well as the parameters and characteristics of its power plant, calculated using the authors algorithm implemented in a complex mathematical model. The results of parametric studies are also presented using the example of assessing the influence of the bypass ratio on the characteristics of a power plant and the parameters of the unmanned aerial vehicle under study. The process of conducting optimization studies of the Unmanned aerial vehicle power plant system with a bypass turbojet engine with mixing of the circuit flows behind the turbine is described. At the same time, special attention is paid to the formulation of the optimization problem, the choice of criteria and changeable variables, as well as the analysis of the results obtained by comparing the efficiency of the system under study with different engine configurations according to the criteria of the aircraft level: maximum range according to two formed flight programs.
{"title":"Determination of the optimal parameters and engine layout for a strike unmanned aerial vehicle","authors":"Yu. V. Zinenkov, A. Lukovnikov, S. Agaverdyev","doi":"10.18287/2541-7533-2022-21-3-23-35","DOIUrl":"https://doi.org/10.18287/2541-7533-2022-21-3-23-35","url":null,"abstract":"The article describes the solution of a complex problem to determine the optimal parameters and engine layout for the power plant of an advanced unmanned aerial vehicle according to the methodology developed by the authors using the authors complex mathematical model and the well-known method of indirect statistical optimization based on self-organization. At the same time, the main aerodynamic and flight performance characteristics of the unmanned aerial vehicle under study, calculated according to engineering methods, are shown, as well as the parameters and characteristics of its power plant, calculated using the authors algorithm implemented in a complex mathematical model. The results of parametric studies are also presented using the example of assessing the influence of the bypass ratio on the characteristics of a power plant and the parameters of the unmanned aerial vehicle under study. The process of conducting optimization studies of the Unmanned aerial vehicle power plant system with a bypass turbojet engine with mixing of the circuit flows behind the turbine is described. At the same time, special attention is paid to the formulation of the optimization problem, the choice of criteria and changeable variables, as well as the analysis of the results obtained by comparing the efficiency of the system under study with different engine configurations according to the criteria of the aircraft level: maximum range according to two formed flight programs.","PeriodicalId":265584,"journal":{"name":"VESTNIK of Samara University. Aerospace and Mechanical Engineering","volume":"85 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133688412","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 : 2022-07-07DOI: 10.18287/2541-7533-2022-21-2-93-99
A. Ryazantsev, S. Yukhnevich, A. Shirokozhuhova
The article considers application areas of various machining methods for perforating holes in parts with unpredictable surface fluctuations. The most effective methods of obtaining holes in parts of a high-frequency ion engine are shown. Studies of perforation technologies using various machining methods have been carried out. Qualitative relations between the geometric dimensions of a spherical billet perforated using a mechanical method, and the quality of the product surface layer are considered. An analysis of modern machining methods is carried out; promising technologies for obtaining holes in parts with a variable profile are presented. The necessity of using high-tech technologies for perforation in high-frequency ion engine parts is justified. The results obtained allow us to significantly expand the production technological capabilities, as well as significantly improve the technical characteristics of special equipment products in mechanical engineering.
{"title":"Creation of promising technologies for producing holes in parts of a high-frequency ion engine","authors":"A. Ryazantsev, S. Yukhnevich, A. Shirokozhuhova","doi":"10.18287/2541-7533-2022-21-2-93-99","DOIUrl":"https://doi.org/10.18287/2541-7533-2022-21-2-93-99","url":null,"abstract":"The article considers application areas of various machining methods for perforating holes in parts with unpredictable surface fluctuations. The most effective methods of obtaining holes in parts of a high-frequency ion engine are shown. Studies of perforation technologies using various machining methods have been carried out. Qualitative relations between the geometric dimensions of a spherical billet perforated using a mechanical method, and the quality of the product surface layer are considered. An analysis of modern machining methods is carried out; promising technologies for obtaining holes in parts with a variable profile are presented. The necessity of using high-tech technologies for perforation in high-frequency ion engine parts is justified. The results obtained allow us to significantly expand the production technological capabilities, as well as significantly improve the technical characteristics of special equipment products in mechanical engineering.","PeriodicalId":265584,"journal":{"name":"VESTNIK of Samara University. Aerospace and Mechanical Engineering","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114778531","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 : 2022-07-07DOI: 10.18287/2541-7533-2022-21-2-28-37
К вопросу, Нормирования Диагностических, Признаков Износа, Зубьев Редукторов, А. Е. Сундуков
The gearboxes of aircraft gas turbine engines are their most stressed parts. One of the main gearbox defects is the tooth flank wear that causes resonant oscillations in engine structure elements. This defect is generally assessed using vibroacoustic diagnostics methods. It is noted that the currently existing recommendations on setting limit values for diagnostic indicators do not take into account the type of mathematical models that describe their dependence on the defect size. This can result in its uncontrolled development. We have shown that for the case under consideration, four kinds of mathematical models were earlier obtained to describe dependences of diagnostic indicators on the wear value: linear, power, exponential and combined (linear and exponential) models. The linear model is characterized by a constant rate of change in the level of a diagnostic indicator with the growth of wear. For power and exponential models the growth of wear leads to an increase of the rate of change in the diagnostic indicator value. The combined model is characterized by the presence of two zones of change in the diagnostic indicator intensity with the growth of wear: the constant rate zone and the zone of increasing rate. The use of diagnostic indicators with a continuous increase in their intensity depending on the growth of wear will require ensuring constant control of the gearbox vibration state, which is not always feasible. We give recommendations for setting standard values of the diagnostic indicator intensity for the considered models.
{"title":"Standardization of diagnostic indicators of gearbox teeth wear in aircraft gas-turbine engines","authors":"К вопросу, Нормирования Диагностических, Признаков Износа, Зубьев Редукторов, А. Е. Сундуков","doi":"10.18287/2541-7533-2022-21-2-28-37","DOIUrl":"https://doi.org/10.18287/2541-7533-2022-21-2-28-37","url":null,"abstract":"The gearboxes of aircraft gas turbine engines are their most stressed parts. One of the main gearbox defects is the tooth flank wear that causes resonant oscillations in engine structure elements. This defect is generally assessed using vibroacoustic diagnostics methods. It is noted that the currently existing recommendations on setting limit values for diagnostic indicators do not take into account the type of mathematical models that describe their dependence on the defect size. This can result in its uncontrolled development. We have shown that for the case under consideration, four kinds of mathematical models were earlier obtained to describe dependences of diagnostic indicators on the wear value: linear, power, exponential and combined (linear and exponential) models. The linear model is characterized by a constant rate of change in the level of a diagnostic indicator with the growth of wear. For power and exponential models the growth of wear leads to an increase of the rate of change in the diagnostic indicator value. The combined model is characterized by the presence of two zones of change in the diagnostic indicator intensity with the growth of wear: the constant rate zone and the zone of increasing rate. The use of diagnostic indicators with a continuous increase in their intensity depending on the growth of wear will require ensuring constant control of the gearbox vibration state, which is not always feasible. We give recommendations for setting standard values of the diagnostic indicator intensity for the considered models.","PeriodicalId":265584,"journal":{"name":"VESTNIK of Samara University. Aerospace and Mechanical Engineering","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129139506","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 : 2022-07-07DOI: 10.18287/2541-7533-2022-21-2-48-64
A. Balyakin, M. Oleynik, E. P. Zlobin, D. Skuratov
This article provides an overview of the latest developments in the field of hybrid additive manufacturing of metal parts. The concept and various kinds of additive manufacturing are discussed. Special attention is paid to hybridization of additive technologies and various processes of forming: die forging, deep drawing, and others. The background and significance of the technologies, as well as their applicability in production are presented. The combination of additive manufacturing with forming processes is carried out with a dual purpose: to expand the area of application of additive manufacturing and overcome its limitations associated with low productivity, metallurgical defects, surface roughness and lack of dimensional accuracy; new application of traditional forming processes.
{"title":"A review of hybrid additive manufacturing of metal parts","authors":"A. Balyakin, M. Oleynik, E. P. Zlobin, D. Skuratov","doi":"10.18287/2541-7533-2022-21-2-48-64","DOIUrl":"https://doi.org/10.18287/2541-7533-2022-21-2-48-64","url":null,"abstract":"This article provides an overview of the latest developments in the field of hybrid additive manufacturing of metal parts. The concept and various kinds of additive manufacturing are discussed. Special attention is paid to hybridization of additive technologies and various processes of forming: die forging, deep drawing, and others. The background and significance of the technologies, as well as their applicability in production are presented. The combination of additive manufacturing with forming processes is carried out with a dual purpose: to expand the area of application of additive manufacturing and overcome its limitations associated with low productivity, metallurgical defects, surface roughness and lack of dimensional accuracy; new application of traditional forming processes.","PeriodicalId":265584,"journal":{"name":"VESTNIK of Samara University. Aerospace and Mechanical Engineering","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123392805","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 : 2022-07-07DOI: 10.18287/2541-7533-2022-21-2-100-108
B. M. Silayev, I. Barmanov
Parts of rolling bearings lubricated with low-viscosity fluids are subject to intense wear of the working surfaces. The bearing life cycle under these conditions depends on the wear rate of the friction surfaces. Therefore, it is important to establish the relationship between the wear rate, the change in the clearances and the duration of work. This paper presents the results of wear tests for rolling ball bearings. After the tests the radial and axial clearances were measured, their changes and the duration of operation were analyzed. Having determined the path of friction, the wear rates of the bearings were calculated based on the values of changes in the radial and axial clearances. The wear rate of the bearing on the axial and radial clearances was plotted against the reduced (equivalent) load. The obtained dependences were approximated with a confidence of at least 98%. The obtained analytical expressions allow us to perform express calculations for changes in the bearing clearances. This will make it possible to forecast the bearing service time, taking into account the wear of the working surfaces under specified conditions, while ensuring correct functioning of the support assembly.
{"title":"Predicting changes in radial and axial clearances in ball bearings lubricated with low-viscosity liquids","authors":"B. M. Silayev, I. Barmanov","doi":"10.18287/2541-7533-2022-21-2-100-108","DOIUrl":"https://doi.org/10.18287/2541-7533-2022-21-2-100-108","url":null,"abstract":"Parts of rolling bearings lubricated with low-viscosity fluids are subject to intense wear of the working surfaces. The bearing life cycle under these conditions depends on the wear rate of the friction surfaces. Therefore, it is important to establish the relationship between the wear rate, the change in the clearances and the duration of work. This paper presents the results of wear tests for rolling ball bearings. After the tests the radial and axial clearances were measured, their changes and the duration of operation were analyzed. Having determined the path of friction, the wear rates of the bearings were calculated based on the values of changes in the radial and axial clearances. The wear rate of the bearing on the axial and radial clearances was plotted against the reduced (equivalent) load. The obtained dependences were approximated with a confidence of at least 98%. The obtained analytical expressions allow us to perform express calculations for changes in the bearing clearances. This will make it possible to forecast the bearing service time, taking into account the wear of the working surfaces under specified conditions, while ensuring correct functioning of the support assembly.","PeriodicalId":265584,"journal":{"name":"VESTNIK of Samara University. Aerospace and Mechanical Engineering","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134129372","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 : 2022-07-07DOI: 10.18287/2541-7533-2022-21-2-7-15
A. Gishvarov, A. Rakhimov
The Engine Air Particle Separator is considered to be the most important element for maintaining the performance of helicopter engines when operating in dusty air conditions. The intensity of erosion of the elements of the gas-air passage of the gas turbine engine depends on many factors: on the hardness and chemical composition of dust particles, on the fractional composition, sand concentration, engine operating condition etc.Therefore, the development of a method for selecting the optimal values of the Engine Air Particle Separator parameters is a complex multi-criteria and multi-factor task. The present document addresses the selection method of optimal values (geometric dimensions) of the Engine Air Particle Separator parameters in aviation gas turbine engines. The methodology includes six main steps. The choice of optimal values of the Engine Air Particle Separator geometrical parameters is accomplished taking into account three partial criteria for the Engine Air Particle Separator efficiency: the degree of air purification, pressure loss and mass. The Engine Air Particle Separator parameters are selected using the Pareto method. An example of choosing the optimal values of the geometric parameters of a cyclone Engine Air Particle Separator is considered.
{"title":"Justification of geometric parameters of the engine air particle separator","authors":"A. Gishvarov, A. Rakhimov","doi":"10.18287/2541-7533-2022-21-2-7-15","DOIUrl":"https://doi.org/10.18287/2541-7533-2022-21-2-7-15","url":null,"abstract":"The Engine Air Particle Separator is considered to be the most important element for maintaining the performance of helicopter engines when operating in dusty air conditions. The intensity of erosion of the elements of the gas-air passage of the gas turbine engine depends on many factors: on the hardness and chemical composition of dust particles, on the fractional composition, sand concentration, engine operating condition etc.Therefore, the development of a method for selecting the optimal values of the Engine Air Particle Separator parameters is a complex multi-criteria and multi-factor task. The present document addresses the selection method of optimal values (geometric dimensions) of the Engine Air Particle Separator parameters in aviation gas turbine engines. The methodology includes six main steps. The choice of optimal values of the Engine Air Particle Separator geometrical parameters is accomplished taking into account three partial criteria for the Engine Air Particle Separator efficiency: the degree of air purification, pressure loss and mass. The Engine Air Particle Separator parameters are selected using the Pareto method. An example of choosing the optimal values of the geometric parameters of a cyclone Engine Air Particle Separator is considered.","PeriodicalId":265584,"journal":{"name":"VESTNIK of Samara University. Aerospace and Mechanical Engineering","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131993061","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：