Browsing by Author "Horobets, Volodymyr L."

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About the Evaluation of the Longitudinal Forces Level Effecting the Track Displacement at Transient Modes of Train Movement
(Дніпропетровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпропетровськ, 2015) Masleieva, Liudmyla H.; Ursuliak, Liudmyla V.; Arsonov V. V.
EN: Purpose. Study the transient modes effect of movement on the track displacement for the freight train safety control is supposed in this paper. For this it is necessary to investigate the longitudinal dynamics of a train on the track displacement. Simultaneously to assess the longitudinal forces level of a track and rolling stock interaction. Methodology. The level of the longitudinal forces, effecting the track displacement, was evaluated using mathematical modeling of longitudinal vibrations of the trains at transient modes of motion caused by braking. It was considered that each train vehicle consists of a body (solid) and the wheel sets, connected with the body by friction bearings (inelastic link). It was believed that during the movement of each train vehicle the vertical plane of its symmetry coincident with the vertical plane of symmetry of the assembled rails and sleepers. At simulation it was also supposed that in the process of translational motion of the vehicle body wheels make pure rolling along the rail without slipping on it. Findings. In the results of calculations the values of the longitudinal forces at different types of braking were obtained (it is regenerative braking and pneumatic one) under quasi-static and shock transients. For this various initial state of clearances in the inter-car connections up to beginning of transient was considered. The level of dynamic additives to longitudinal forces of interaction between wheel and rail that are substantially depending on vehicle accelerations was assessed. Originality. The transient regimes effect of trains movement caused by braking on the level of the longitudinal forces of track and rolling stock interaction was investigated. The longitudinal load of freight trains with regenerative and pneumatic braking was researched. The effect of the initial state of the train and different modes of braking on a dynamic additive to the longitudinal forces of the interaction between the track and rolling stock, which may effect the displacement of assembled rails and sleepers, was estimated. Practical value. The obtained results can be used to select rational modes of braking of freight trains, especially on lengthy down grade, from the positions prevent possible track displacement.
A Combinatorial Mathematical Model of the Dynamics of the Incidence of Covid-19 on the Example of the Situation in the Ukraine
(Sergeieva&Co, Karlsruhe, Ukraine & Germany, 2024) Sablin, Oleg I.; Zelenko, Yuliia V.; Horobets, Volodymyr L.
UKR: Автори на основі дослідження широкого спектру статистичних даних запропонували математичну модель динаміки поширення COVID-19 та інших подібних інфекцій. Запропонована модель допомагає зрозуміти механізми виникнення гострих респіраторних вірусних інфекцій.
Comparative Tests of Contact Elements at Current Collectors in Order to Comprehensively Assess their Operational Performance
(PC "Technology Center", Ukrainian State University of Railway Transport, Kharkov, Ukraine, 2018) Babyak, Mykola O.; Horobets, Volodymyr L.; Sychenko, Viktor G.; Gorobets, Yevhen
EN: We have studied the interaction between contact elements in the pantographs of electric transport under operation at the sections of railroads powered by direct and alternating current. In contrast to known techniques for bench tests, we investigated the mechanism of current collection and wear resistance at the new testing installation over a minimally narrow region of the sliding contact, simulating the phenomenon of a pantograph “cut”. This installation can be used both industrially when manufacturing new contact elements and under laboratory setting when studying wear resistance. The experimental research confirmed that the wear intensity of contact elements at pantographs depends on current load over a contact area, the magnitude of contact pressure, the area of a contact surface, and motion speed. We have practically proven a possibility to maintain a reliable contact connection in the sliding contact under extreme operating conditions when using a reliable contact material for the current collector pads. It has been proposed to use the powder composition BrIG based on bronze, iron, and graphite, for making contact elements for pantographs that could provide for reliable contact when interacting with the contact wire. Application of new and high-quality contact materials affects the tribology and stability of interaction between plates and the contact wire. Owing to our study, a possibility has been established to manufacture a reliable contact element BrIG, which would prolong the time of interaction in the contact pair “pantograph at electric transport ‒ contact network”. The practical significance of this research relates to the proven efficiency of utilizing the new contact material BrIG for electric railroad transport network, in trolley buses and trams. Thus, one can argue about the possibility to prolong the time of operation for the contact pair “pad in a pantograph at electric transport ‒ contact network” by applying the new contact material BrIG.
Methods and Results of Evaluating the Dual-Power Electric Train Crew Elements Service Life
(IOP Publishing, 2020) Horobets, Volodymyr L.; Sablin, Oleh I.; Fedorov, Yevhen F.; Horobets, Yevhen; Bolotov, Oleksij O.; Jangulova, Olga L.
EN: The article assesses the long-term strength of the vibration damper assembly of a double power transmission of electric trains manufactured by «Hyundai-Rotem Company». The technique is described and the analysis of the service life of the elements of the chassis of the electric train is made. The presence and nature of micro cracks in the loaded elements of the vibration damper assembly was evaluated after a full cycle of vibration bench tests. The influence of vertical vibrations of the electric train body on the level of dynamic load and the service life of the bearing elements of the vibration damper assembly is considered. The service life of the vibration damper at the end of the service life has been estimated by comparing working hours and “statistical playback”. The calculation of the resource by the method of "statistical reproduction" confirms the possibility of operating the vibration damping module (second modernization) for 50 years from the date of construction. The influence of the vibration damper position on its dynamic loading is checked. The main stages and sequence of tests for estimation the resource of the longitudinal vibration damper module of a double-fed electric train are also considered, including methodological, calculated and experimental confirmation of the reliability and durability of the unit, which was studied as part of a comprehensive work.
Revealing the Effect of Structural Components Made of Sandwich Panels on Loading the Container Transported by Railroad
(РС ТЕСHNOLOGY СЕNTЕR, Kharkiv, 2023) Vatulia, Glib; Lovska, Alyona O.; Myamlin, Sergiy S.; Stanovska, Iraida; Holofieieva, Maryna; Horobets, Volodymyr L.; Nerubatskyi, Volodymyr; Krasnokutskyi, Yevhen
ENG: The object of this study is the processes of emergence, perception, and redistribution of loads in the supporting structure of a 1CC size container with end walls made of sandwich panels. To reduce the longitudinal load of the container under operational modes, the introduction of sandwich panels into its design is proposed. This solution is implemented on the example of its end walls as the most loaded component of the body in operation. The thickness of the sandwich panel sheet was determined, provided that the strength in operation is ensured. Mathematical modeling of dynamic load of a container with end walls made of sandwich panels placed on a platform car during shunting co-impact was carried out. It was established that taking into account the proposed improvement makes it possible to reduce the dynamic loads that the container perceives by 10 % compared to the typical structure. The results were confirmed by computer simulation of the dynamic load of the container. The models formed within the framework of the study were verified according to the F-criterion. The results of calculations for the strength of the container showed that the stresses in its structure are 15 % lower than those in the typical one. A feature of the findings is that the proposed improvement of the container helps improve its strength in operation by reducing the loads acting on it. The scope of practical use of the results is the engineering industry, namely, railroad transport. At the same time, the conditions for the practical application of the research results are the introduction of energy-absorbing material as a component of the sandwich panel. This study will contribute to devising recommendations for designing modern structures of vehicles of a modular type and for improving the efficiency of the transport industry.
Study of Car Traffic Flow Structure on Arrival and Departure at the Marshalling Yard X
(Дніпропетровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпропетровськ, 2016) Nesterenko, Galina I.; Muzykin, Mykhailo I.; Horobets, Volodymyr L.; Muzykina, Svetlana I.
ENG: The paper is aimed to analyse the existing car traffic organization at the marshalling yard aimed to reduce downtime of cars. Methodology. The methods of mathematical statistics allowed building the histogram of car traffic flow distribution at the marshalling yard and assessment of their parameters. The key quantitative and qualitative indicators of the station operation were analyzed. In order to analyze the effect of rehandling volume on the rehandled transit car downtime elements at the station we plotted the dependence graph of the car downtime elements on the rehandling volume. The curve variation on the graph clearly shows the effect of rehandling volume on two downtime elements: during formation and in expectation of operations. Findings. The question of reducing the average downtime of all car categories at the station should be solved by reducing unproductive downtime was proved. The correct determination of the average time spent by a rehandled transit car at the station is essential, especially in the conditions of new system of economic incentives. But still there is no separate methodology for determining the car downtime, which would allow to objectively consider the equipment and operation technology and exclude the possibility for subjective decisions. Originality. One of the main kinds of unproductive downtime during the carriage of goods by rail is a downtime on the marshalling yards in expectation of technological operations because of the system congestion. Reduction of this indicator is possible due to rational use of the marshalling yard capacity provided the rational distribution and car – and train flows between the major marshalling yards of Ukrzaliznytsia. Practical value. The analysis of changes in downtime elements, depending on the rehandling volume allows not only to identify the car downtime reduction methods, but also to make a correct assessment of station staff work, as well as to adjust the rate of idle wagons.
Working Capacity Research of Track Sections
(Silesian University of Tecnology, Katowice, Poland, 2017) Nesterenko, Halyna I.; Muzykin, Mykhailo I.; Horobets, Volodymyr L.; Avramenko, Svetlana I.
ENG: Abstract. The paper identifies the problems and ways to implement the measures to increase the working and carrying capacity of railway lines. The analysis of this problem shows that for Ukrainian rail network there is no holistic approach to formalize procedures for calculating the working capacity of track sections taking into account technological features of passage of individual car traffic volumes. In addition, there are few studies of factors that influence the level of working capacity use. This necessitates research in this area, which can be a basis for calculating working capacity of sections depending on the influence of various factors. The main ways to increase the working and carrying capacity of railway lines are to increase the weight and length of the trains. But it is a difficult complex task. When solving this task it should be considered restrictions on the useful length of station tracks, restrictions on the traction force of locomotives, possible reduction of train service speed, and many other additional factors. Increase of the train weight makes it possible to increase the carrying capacity of railway lines on the average by 10-30%. But the problem of train weight is closely connected with analysis of the length of existing receiving and departure tracks on the main directions of train movement of OJSC "Ukrainian Railways." Having analyzed the working capacity reserve at all the existing lines of Dnipropetrovsk Management of Rail Transportations we can conclude that the available working capacity exceeds the required one (the reserve is sufficient).