Випуск 51

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ЗАГАЛЬНІ ВІДОМОСТІ ПРО ЖУРНАЛ
(Харківський національний автомобільно-дорожній університет, 2022)
Risk modeling in working out the plan of developing the road transport cargo enterprise
(Харківський національний автомобільно-дорожній університет, 2022) Shevchenko, Inna; Dmytriiev, Illia; Dmytriieva, Oksana; Шевченко, Інна Юріївна; Дмитрієв, Ілля Андрійович; Дмитрієва, Оксана Іллівна
Problem. In recent years, there has been a rather stable trend of reorientation of the freight transportation market in Ukraine from the predominant use of rail transport to customers preferring road transport for moving goods. Relying on the indicated trend and the prospect of its preservation in view of the indisputable manoeuvre advantages of road transport in the conditions of martial law, the study of the problematic issues of the development of road transport cargo enterprises, among which the risk modeling of their operational activities occupies a prominent place, becomes relevant. Goal. The purpose of the scientific work is to study the methodological and applied aspects of risk modeling when working out a plan for developing a cargo enterprise of road transport. Methodology. The method of analysis and synthesis, system approach, observation method, comparative analysis, factor analysis method, simulation modeling method, and experimental method were used in the work to study the methodological and applied aspects of risk modeling when elaborating a plan for developing a road transport cargo enterprise. Results. The risk model presented in the study makes it possible to identify the optimal level of risk when elaborating a plan for development of a road transport cargo enterprise based on variants of the key indicator of the volume of cargo transportation (including financial indicators). Originality. In the process of modeling in one cycle, you can get up to 24 different options for the values of the optimal level of risk for the implementation of the plan for development of the road transport cargo enterprise, taking into account the differentiation of the parameters of the risk model, in particular, six options for the distance of cargo transportation and four classes of cargo. Practical value. The proposed methodical approach to risk modeling when working out a plan for developing a road transport cargo enterprise takes into account the probable change in demand for freight transportation, which gives the enterprise the opportunity to quickly respond to changes in market conditions and successfully plan activities in conditions of incomplete certainty, lack of information and the presence of risk.
Electric vehicles and energy-saving technologies – master's degree program under the Erasmus project Cybphys
(Харківський національний автомобільно-дорожній університет, 2022) Hnatov, Andrii; Arhun, Shchasiana; Гнатов, Андрій Вікторович; Аргун, Щасяна Валіковна
Problem. The quality of higher education is achieved by compliance with the conditions for the implementation of educational activities and learning outcomes with the requirements of legislation and higher education standards, professional and international standards, as well as the needs of stakeholders and society. Obviously, the requirements, recommendations and opinions of stakeholders play one of the main roles in the process of ensuring the quality of higher education. It should be noted that without ensuring and improving the quality of higher education, it is impossible to obtain accreditation of an educational program (EP) in the relevant specialty. Goal. Analysis and processing of feedback received from employers and representatives of the academic community who have experience in working and teaching in the 141 specialty "Electric Power Engineering, Electrical Engineering and Electromechanics" to improve the quality of education under the master's EP "Electric vehicles and energy-saving technologies". Methodology. The method of questioning consists in obtaining information by means of written answers of respondents to a system of standardized questions. Methods of information processing and synthesis method - the study of an object in its integrity, in the unity and interconnection of its parts. Results. An analytical review of decisions on EP and publications on the introduction of innovative teaching methods and methods of maintaining the quality of the educational process into the educational process was carried out. In a number of educational components, the list of literature will be expanded due to the technical documentation of automakers and references to modern research by foreign authors. It is proposed to improve the existing and develop new laboratory and practical work on modern equipment purchased through the «CybPhys» project and on the equipment of interested employers. It is proposed to expand the practice of the educational components of the EP related to the cycle of professional training disciplines. It is proposed to add the topic "Alternative power sources" to the cycle of disciplines of the applicant's free choice (professional training section). Originality. It is proposed to conduct practical and laboratory classes and conduct research on the topic of the thesis directly in production and in the daily work of service stations and car service. Practical value. Based on the results of the feedback received from stakeholders, appropriate changes will be made to the courses that will improve the quality of education and make the master's EP "Electric vehicles and energy-saving technologies" even more relevant and actual for the labor market in the field of electric power, electrical engineering and electromechanics, in particular, with regard to the industry electric vehicles and energy saving technologies.
Two inverse non-stationary problems of axially symmetric deformation of a finite-length elastic cylindrical shell
(Харківський національний автомобільно-дорожній університет, 2022) Voropay, Alexey; Povaliaiev, Serhii; Sharapata, Andrey; Воропай, Олексій Валерійович; Поваляєв, Сергій Іванович; Шарапата, Андрій Сергійович
Problem. Among the many problems of the solid mechanics, there is a whole class of problems that are related to inverse problems. In turn, among the inverse problems, many problems are ill-posed. Obtaining an exact analytical solution of such problems is related to certain mathematical difficulties and requires using special methods. Goal. The goal of the study is to obtain analytical solutions for inverse problems of the identification of non-stationary load and the control of nonstationary vibrations of a cylindrical shell with asymmetric boundary conditions. Methodology. In this investigation, a refined theory of medium-thickness shells was used. Fourier series expansion, the theory of integral equations and the Laplace transform were used to obtain the solution of the direct problem. Tikhonov’s regularization method was used to solve inverse problems. Results. As a result of the investigation, the solutions of two inverse problems of the solid mechanics were obtained. The first task is to identify a fixed and moving concentrated axisymmetric non-stationary force acting on a cylindrical shell, based on the displacement values at any point of the shell; identification of two fixed concentrated forces. The second task is to control vibrations at any point of the cylindrical shell by introducing an auxiliary concentrated force. Numerical results obtained demonstrate the fulfillment of the control criterion as a result of the action of the given and auxiliary force. Originality. Analytical solutions of the inverse problems of the solid mechanics for a cylindrical shell of medium thickness with asymmetric boundary support conditions are obtained. Practical value. The technique received allows effective identification of an unknown non-stationary load. It’s important for the rational design of reliable cylindrical shell structures. Its use also makes possible to create a theoretical basis to control the deflected mode parameters of cylindrical shell structural elements.
Introduction of an additional source of harmonic signal into the circuit of the electric power resonant amplifier
(Харківський національний автомобільно-дорожній університет, 2022) Batygin, Yuriy; Shinderuk, Svitlana; Chaplygin, Evgen; Yeryomina, Olena; Tereh, Egor; Батигін, Юрій Вікторович; Шиндерук, Світлана Олександрівна; Чаплигін, Євген Олександрович; Єрьоміна, Олена Федорівна; Терех, Єгор Сергійович
Problem. The problems of the electric power industry, caused by the depletion of the natural resources of the planet and the need to replace them, initiate the development of new physical and technical solutions with the practical use of the known natural phenomena. Goal. The purpose of this work is to propose to introduce an additional source of a harmonic signal (voltage or current) into the circuit of a resonant amplifier of electric power, to obtain calculated analytical dependencies for numerical estimates of the characteristics of ongoing electromagnetic processes, which make it possible to give a fundamental justification for the real performance of the proposed circuit as a whole, taking into account the interaction of all its functional components. Methodology. This work, ultimately, involves the use of resonant phenomena in circuits with active-reactive elements and their theoretical analysis using the mathematical apparatus of the theory of electrical circuits. Results. It is proposed to implement the resonant amplifier circuit in the form of four active-reactive closed circuits inductively coupled to each other. Moreover, in a practical embodiment, inductive couplings can be carried out using HF ferrites. The first circuit is the input circuit with the harmonic power source to be amplified. The second circuit generates amplified reactive power in the "voltage resonance" mode. The third circuit with an additional harmonic voltage source outputs reactive power from the second circuit in the "current resonance" mode. The fourth circuit, inductively coupled to the third circuit, contains the output load of the entire resonant amplifier. This is a resistor that simulates the release of active power. Originality. Physically, the introduction of an additional source in the third circuit is equivalent to the creation of a "negative active resistance", which makes it possible to create conditions for excitation of current resonance with the minimum possible distortion and, ultimately, to reduce the reverse effect on the amplifying processes in the second circuit (reactive power amplifier). The analysis and numerical evaluation of the characteristics of the proposed scheme of the active electric power resonant amplifier showed its fundamental viability. Practical value. As an example, calculations of currents and voltages in the circuit of an experimental model were made, which enabled to formulate recommendations for the selection of elements of a real active electric power amplifier with high efficiency for low-resistance output loads.
Analysis of the load-bearing system of the loader according to the results of dynamic tests in the environment of Ansys motion
(Харківський національний автомобільно-дорожній університет, 2022) Shcherbak, Oleh; Ragulin, Vitaliy; Suminov, Andrii; Щербак, Олег Віталійович; Рагулін, Віталій Миколайович; Сумінов, Андрій Володимирович
Problem. The T-156B hinge frame of the loader, which is an upgraded frame of an agricultural tractor, creates loads during work operations for which it was not designed. Such loads lead to breakdowns and further shorten the life of the entire machine. The frame is the basic element around which the machine is built. The loader that had just been removed from the conveyor did not have builtin durability and reliability. While designing a road construction machine, an account of the features, nature, and conditions of its operation should be taken. Goal. The goal is to develop a hinge frame design technique that takes into account the loads experienced by the frame with a virtual simulation of real-world situations during the loader process. Methodology. The adopted approach is based on the use of a Solidworks computer program with three-dimensional modeling and an Ansys motion program for calculating the dynamics of multicomponent bodies taking into account the hinge and contact interaction. Results. In the work three cases of technological operations of the loader were considered. 1. Lifting a full bucket. 2. Collision with an obstacle that is difficult to overcome 3. Movement over an uneven surface with the raised loader arm. The results of the calculations provided forces and torques in the hinge of the half-frames, as well as the effort of the frame. Based on the results obtained, the endurance of the frame in the Ansys motion software package was calculated. Originality. The analysis of load-bearing systems with a virtual simulation of the machine’s actual behavior with the help of Ansys motion software allows to obtain more accurate results, significantly reducing the time for the design and cost of field testing. Practical value. This approach to the analysis of the carrier system behavior can be recommended for designing and determining the technological capabilities of wheeled, tracked, and special machines.
On the issue of using expenditure functions in simulation of pneumatic links of the "throttle - capacity" type
(Харківський національний автомобільно-дорожній університет, 2022) Leontiev, Dmytro; Savchenko, Yevhen; Harmash, Anton; Suhomlyn, Oleksandr; Sinelnik, Danylo; Леонтьєв, Дмитро Миколайович; Савченко, Євген Лукич; Гармаш, Антон Андрійович; Сухомлин, Олександр Вячеславович; Cінельнік, Данило Богданович
Problem. When studying the work processes that occur in pneumatic or electropneumatic circuit of brake systems or pneumatic suspension systems of a wheeled vehicle, researchers use various expenditure functions on the basis of which they draw scientific conclusions and obtain scientific results, while they do not think about the fact that the functions are credible or not. The choice of the expenditure function, for researchers, is an actual scientific task, which should have a scientific justification and should not have a formalized nature. Goal. The aim of the study is to compare the expenditure functions to determine the nature of their influence on the dynamic processes that occur during filling or emptying links of the pneumatic circuit. Methodology. The approaches adopted in the work to solving the set goal are based on the analysis of the results of simulation modeling of work processes in pneumatic circuit. Results. A comparison of the research results obtained in this work with each other and with the results obtained in experimental studies, allowed us to establish the peculiarities of the course of work processes in the pneumatic circuit links when using different expenditure functions. It was established that, depending on the choice of the expenditure function, with the same initial conditions of simulation modeling, the results of the study can differ by up to 40%. Originality. The use of a universal basis of simulation modeling, based on various expenditure functions, enabled to establish that it is possible to propose new functions that better describe the working process in a pneumatic circuit than the known ones. Practical value. The obtained results can be recommended in the practice of simulation modeling of work processes in pneumatic or electropneumatic circuits of brake systems and systems of pneumatic suspension of wheeled vehicles.
Analysis of design features of systems and components of the Tesla Model S electric car
(Харківський національний автомобільно-дорожній університет, 2022) Smyrnov, Oleh; Borysenko, Anna; Смирнов, Олег Петрович; Борисенко, Анна Олегівна
Problem. The article analyzes the design features of the systems and components of the Tesla Model S electric car, which allows choosing the initial characteristics for the mathematical model of the acceleration dynamics of the electric car, determines the cost characteristics of its power plant (electric motor) and battery. Goal. The purpose of the work is to determine the initial characteristics of the systems and components of a modern electric vehicle for their further use in a mathematical model of the acceleration dynamics of an electric vehicle. Methodology. The approaches adopted in the work to achieve the set goal include understanding the peculiarities of the initial characteristics of the systems and components of electric vehicles, which are the world leaders in the market of such vehicles. Results. In the work, a comparative analysis of the layout schemes for the implementation of transmissions in the designs of modern electric vehicles, the characteristics of their power plants (electric motors), the characteristics of energy converters (inventories), and the features of the power plant power plant of a modern electric car are determined. Originality. The conducted analysis of the design features of systems and components of the Tesla Model S electric car made it possible to form a general idea about the features of the implementation of work processes in the electric drive of an electric car, which can be used as initial parameters or characteristics during the simulation of the acceleration dynamics of an electric car. Practical value. The obtained results make it possible to formulate recommendations for the use of the characteristics of the systems and components of the electric vehicle during the simulation of the dynamics of its acceleration and to determine the energy consumption in the power system of its traction electric drive.
Assessment of increased energy efficiency of vehicles with a rational reduction of engine capacity
(Харківський національний автомобільно-дорожній університет, 2022) Podrigalo, Mikhail; Tarasov, Yurii; Kholodov, Mykhailo; Shein, Vitaly; Tkachenko, Olexander; Kasianenko, Oleksii; Подригало, Михайло Абович; Тарасов, Юрій Володимирович; Холодов, Михайло Павлович; Шеїн, Віталій Сергійович; Ткаченко, Олександр Сергійович; Касьяненко, Олексій Віталійович
Problem. The tendency to reduce Engine displacement, which has emerged in recent years in the global automotive industry, is due to the need to improve the environmental situation and energy efficiency of vehicles. Goal. The aim of the study is to increase the energy efficiency of vehicles by rationally reducing the maximum effective engine capacity. Methodology. In the paper authors used the method of partial accelerations implemented in a mobile registration and measurement complex, which allowed authors to obtain an improved formula for calculating aerodynamic drug. Experimental studies of car aerodynamics were also conducted. Results. In the study presents the results of the authors' research, which made it possible to prove the possibility of reducing the e internal combustion engine capacity while maintaining the specified maximum speed and the specified level of indicators of the car dynamic properties. Originality. The relationship between the use of maximum engine capacity and the relative change in the effective specific fuel consumption of a carburetor gasoline engine, with direct injection of gasoline and diesel were determined. Practical value. Calculations performed on the example of the ZAZ-1103 "Slavuta" car showed that a rational reduction in effective engine capacity allows to reduce fuel consumption by 9.5% for carburetor gasoline engine, and for an engine with direct injection of gasoline by 6.7 % and for diesel engines, by 20.3%.
Determination of the average torsional stiffness of tires of a double vehicle wheel during its interaction with the road surface
(Харківський національний автомобільно-дорожній університет, 2022) Leontiev, Dmytro; Frolov, Andrii; Леонтьєв, Дмитро Миколайович; Фролов, Андрій Анатолійович
Problem. In the scientific and methodological recommendations of forensic institutions and in the scientific and technical literature there are currently no universal methods for determining the braking parameters of cargo multi-axle vehicles that have wheels with double tires, which affects the results of drawing up the conclusions of the motor-technical expertise. The lack of universal methods is due to the difficulty of determining the actual braking, especially when the tires of dual wheels interact with the road surface. Goal. The goal is justification of the method of determining the average torsional stiffness of tires of a double vehicle wheel during its interaction with the road surface. Methodology. The approaches adopted in the work to achieve the set goal are based on the theoretical foundations of the deformation of elastic elements, which are located parallel to each other. Results. Equations are determined that allow you to calculate the value of the average torsional stiffness of the tire for wheels that have double, triple or quadruple tires. Originality. The results of the research provide a general idea of the effect of the pressure in the tires of a double wheel on the value of its average torsional stiffness. Practical value. The obtained results can be recommended to expert motor technicians when drawing up a conclusion of an expertise or an expert study. Besides, the results of the study can be used in the educational process during the training of specialists in the field of transport or mechanical engineering.
Refined assessment of tire rolling resistance in the starting mode
(Харківський національний автомобільно-дорожній університет, 2022) Karpenko, Volodymyr; Neskreba, Eduard; Карпенко, Володимир Олександрович; Нескреба, Едуард Євгенійович
Rolling resistance is one of the most important operational characteristics of a car tire. First of all, the fuel consumption, durability and service life of the tire depend on the rolling resistance. Of course, the higher the rolling resistance, the faster and more intensively the tire will wear out. Also, car braking parameters, such as deceleration and, accordingly, the braking distance, may indirectly depend on the rolling resistance characteristics. In turn, rolling resistance is influenced by the properties of the tire itself, as well as the condition of the road surface and weather conditions. It is especially important to evaluate the operational characteristics of a car tire in the starting period of movement, because at this time the behaviour of the tire is unpredictable. Goal. The purpose of this work is to improve the methodology for evaluating the rolling resistance of a car tire in the starting period of movement. Knowing how the rolling resistance changes during the starting movement, it is possible to evaluate the operational properties of the car. Methodology. Refined assessment is carried out with the help of dependencies obtained in previous scientific works. But in order for the result of the rolling resistance assessment to be correct, it is necessary to determine the necessary characteristics of the tire. Namely, we are talking about the characteristics of radial stiffness. In the work, these characteristics are determined both by conducting experimental studies and by using FEM. Results. Thanks to the conducted research, significant results were obtained on the change in rolling resistance during the starting motion. It was established that with an increase in internal pressure from 0.17 MPa to 0.225 MPa, as a result of the starting motion, the rolling resistance decreases by approximately 20-25%. Originality. From the analysis of the literature, it can be concluded that in most of the studied works, the peculiarities of the interaction of automobile tires with the supporting surface in the starting period are not taken into account during various studies. It can be said that the originality of this work, on the one hand, is that the rolling resistance is investigated during the starting motion, and on the other hand, that its assessment is carried out both on the basis of the results of experimental studies and with the help of FEM. Practical value. In this work, it is possible to highlight the obtained results, thanks to which we can estimate the rolling resistance of a car tire with sufficient accuracy. The methods of determining the operational characteristics of a car tire, presented in the work, can be used during its operation and at the design stage.

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