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Adaptation of Ukrainian Grain Elevators for Unit Train Loading
(Kaunas University of Technology, Kaunas, Lithuania, 2018) Kozachenko, Dmytro M.; Bobrovsky, Volodymyr I.; Ochkasov, Oleksandr B.; Shepotenko, Anatolii P.; Hermaniuk, Yuliia M.
ENG: The aim of the paper is to improve approaches to the design and operation of private sidings of grain elevators for loading of unit trains. The research is based on the methods of organizing of railway operation. One of the main methods of reducing costs in the logistics chain, which provides for the export of grain cargoes is the using of unit train technology for transportation. Introduction of this technology in Ukraine is limited by the low loading capacity of elevators. In the paper the basic schemes of track development of elevator private sidings and analyzes the use of different technical means for performing shunting operations are presented. The results of the performed research can be used for designing and reconstruction of the existing elevators and for building the new ones, as well as for estimating the costs associated with different logistic schemes for grain delivery to seaports. As result the work develops a methodology and obtains a technical-operational assessment of the technical equipment and the operation technology grain elevator private sidings for loading of unit trains.
Analysis of the Electric Energy Consumption Components for Mine Train Traction
(Dnipro National University of Railway Transport named after Academician V. Lazaryan, 2019) Arpul, Serhii V.; Artemchuk, Viktor V.; Babyak, Mykola O.; Vasilyev, Viacheslav E.; Hetman, Hennadii K.; Marikutsa, Serhii L.
EN: Abstract. The paper considers the issues of reducing the energy intensity of transportation at opencast mining enterprises, the relevance of which has now increased due to the rise in the cost of fuel and energy resources. It presents the study results concerning the cost structure of the electricity consumed by electric mine transport, which form the basis for the development of technical and operational measures to reduce the energy intensity of the transportation process. It is shown that the work to reduce the electricity consumption for mined rock transportation should be aimed at: - Reduction of losses in the power circuits of the traction rolling stock due to the use of more advanced electric rolling stock and regulation of the degree of utilization of the installed traction power; - Introduction of new contact materials for electrical circuits with the lowest possible resistivity, including for current collector plates; - Introduction of measures to reduce energy consumption for power supply of auxiliary circuits; - Development and implementation of rational train control techniques. The introduction of energy-saving measures should include the development and application of effective methods for calculating individual norms of energy consumption and incentives for energy saving of the employees involved in the organization of the transportation process.
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.
A Comprehensive Procedure for Estimating the Stressedstrained State of a Reinforced Concrete Bridge Under the Action of Variable Environmental Temperatures
(РС ТЕСHNOLOGY СЕNTЕR, Kharkiv, Ukraine, 2021) Kovalchuk, Vitalii V.; Onyshchenko, Artur; Fedorenko, Olexander; Habrel, Mykola; Parneta, Bogdan Z.; Voznyak, Oleh M.; Markul, Ruslan V.; Parneta, Mariana; Rybak, Roman
ENG: This paper reports the full-scale experimental measurements of temperature distribution over the surfaces of bridges’ steel-concrete beams under the influence of positive and negative ambient temperatures. It has been established that the temperature is distributed unevenly along the vertical direction of a bridge’s steel-concrete beam. It was found that the metal beam accepted higher temperature values. The maximum registered temperature difference between a metal beam and a reinforced concrete slab at positive ambient temperatures was +9.0 °C, and the minimum temperature difference was −2.1 °C. The mathematical models for calculating a temperature field and a thermally strained state of bridges’ steel-concrete beams under the influence of variable climatic temperature changes in the environment have been improved, taking into consideration the uneven temperature distribution across a bridge’s reinforced concrete beam. The possibility has been established to consider a one-dimensional problem or to apply the three-dimensional estimated problem schemes as the estimation schemes for determining the thermoelastic state of reinforced concrete bridges. The temperature field and the stressed state of bridges’ reinforced concrete beams were determined. It was found that the maximum stresses arise at the place where a metal beam meets a reinforced concrete slab. These stresses amount to 73.4 MPa at positive ambient temperatures, and 69.3 MPa at negative ambient temperatures. The amount of stresses is up to 35 % of the permissible stress values. The overall stressed-strained state of a bridge’s reinforced concrete beams should be assessed at the joint action of temperature-in- duced climatic influences and loads from moving vehicles.
Development of an Algorithm for Investigation of Technical State of Wagons’ Running Gears During Their Derailment
(Dnipro National University of Railway Transport named after Academician V. Lazaryan, 2019) Batig, Andriy V.; Hrytsyshyn, Petro; Kuzyshyn, Andriy; Milyanych, Andriy R.; Voznyak, Oleh M.; Tereshchak, Yuriy V.
EN: Abstract. A freight wagon is a collection of a large number of parts and assemblies that form a single structure. During wagon operation, there are gradual changes in the characteristics and parameters of its structural elements. That is, the parameters of its constituent elements change – their numerical values increase or decrease that result in a change of the unit’s technical state, and, in turn, affects the totality of its performance. Gradually accumulating, the changes in the parameters of the structural elements of a wagon reach such a level that radical, sometimes abrupt qualitative change occurs. A malfunction that has not been repaired timely may lead to a failure of a wagon structural element, which, in turn, may result in rolling stock derailment. It has been established that the loss of stability of freight wagons during their movement is most often due to their unsatisfactory dynamic properties, which can be explained by design features and technical state of running gears. In this regard, the authors of the article have developed an algorithm for investigation technical state of running gears of freight wagons and determined the effect of their parameters’ deviation on rolling stock operation with possible further derailment.
Development of Mathematical Models of Energy Conversion Processes in an Induction Motor Supplied from an Autonomous Induction Generator with Parametric non-Symmetry
(НВП ПП «Технологічний Центр», Харьків, 2021) Chenchevoi, Volodymyr; Kuznetsov, Valeriy; Kuznetsov, Vitalii; Zachepa, Iurii; Chencheva, Olga; Chornyi, Oleksii; Kovzel, Maksim; Kovalenko, Viktor; Babyak, Mykola O.; Levchenko, Serhii
ENG: The paper presents studies of the system “induction generator-induction motor” with parametric asymmetry on a mathematical model to determine the quality of generated electricity in load operating modes. A mathematical model of the “induction generator-induction motor” system has been developed taking into account losses in steel and parametric asymmetry. The analysis of the transient characteristics of an induction generator when a motor load is connected in symmetrical and asymmetrical modes of operation is carried out. The results of changes in the main characteristics of an induction motor at various degrees of parametric asymmetry in the generator are presented. The quality of the generated electricity was analyzed based on the calculations of the unbalance coefficients for each of the operating modes. The assessment of the thermal state in steady-state conditions was carried out using an equivalent thermal equivalent circuit. Thermal transients were investigated when starting an induction motor from an autonomous energy source based on an induction generator. On a thermal mathematical model, the study of the effect of the output voltage asymmetry on the heating of the connected induction motor was carried out. It is shown that the asymmetry of the output voltage of an induction generator reaches 3–10 % and causes overheating of the windings in excess of the permissible values. A regression model has been developed for studying the operating conditions of an induction motor when powered by an induction generator with an asymmetry of the stator windings. The use of the obtained equations will make it possible to determine the most rational combination of factors affecting the heating of the stator windings of induction machines, in which they will not overheat above the maximum permissible temperature values of the corresponding insulation classes.
Device for Measuring and Evaluation Stress-Strain State Transport Facilities at Variable Load and Temperature
(Dolnośląskie Wydawnictwo Edukacyjne, Wroclaw, 2015) Luchko, Józef; Kovalchuk, Vladimir; Wozniak, Oleg
EN: In this work the scientific principles of a new device for the measurement and evaluation of the stress-strain state of transportation facilities under changing temperatures and loads. The technical problem which is solved by this work is to adopt the monitored transport facilities evidence-based decisions about the need for renewal of an element, controlling gradual reduction of the bearing capacity of the structural elements, establishing their actual technical condition and residual life. At the heart of the new device is measuring strain using analog-to-digital converter (ADC) and analog measuring bridge-tensometer. The advantage of the proposed device is that the accuracy of measurements made with the help does not depend on the length of the connecting conductors and supply voltage. He can help you evaluate and consider the deformation caused by too, and temperature effects on transport facilities.
Evaluation of the Transition to the Organization of Freight Trains Traffic by the Schedule
(Silesian University of Technology, Poland, 2016) Kozachenko, Dmitriy N.; Vernigora, Roman V.; Balanov, Vladimir O.; Berezovy, Nikolay I.; Yelnikova, Lidiia O.; Germanyuk, Yuliya N.
ENG: The paper considers the issues of bulk conveyance organization between industrial enterprises on schedule. Currently the movement of the main part of freight trains is performed on preparedness and occupation processes of separate schedule train paths by some terminals are not fixed. And, due to the lack of statistical material on the punctuality of the schedule for the movement of freight trains, research of the passenger trains movement with subsequent dissemination of results on freight movement were carried out by the authors. The values of the additional time reserves that should be included in the schedule of trains, and the schedule for the turnover of freight trains to provide conditional interaction of railroads and industrial enterprises in Ukraine were proposed. The obtained results can be used for the technical-and-economic calculations of transition effectiveness of industrial enterprises for maintenance on schedule as well as in the development of schedule on the initial stages of testing technology.
Experimental Study of Railway Trackred Pressure Distribution under Dynamic Loading
(Riga Technical University, Latvia, 2019) Sysyn, Mykola P.; Kovalchuk, Vitalii V.; Nabochenko, Olga S.; Kovalchuk, Yuri; Voznyak, Oleg M.
EN: Abstract. Reliable and durable operation of the railway track under the dynamic load of the rolling stock depends considerably on the ability of the ballast layer to get the load from the sleepers and distribute it to the subgrade. In this paper, the experimental study of the distribution properties of the ballast layer under the impact of dynamic loading depending on the density of the ballast layer is carried out. The ballast behaviour during load cycles is estimated by pressure measurements at the ballast prism base along the axis of a sleeper with simultaneous video observation of the ballast particles movement through transparent sidewalls of the box with crushed stone. Measurements of pressure distribution are carried out with the developed microcontroller system of measurements and developed load cells. The system allows performing multi-point measurements of stress in combination with measurements of acceleration and photogrammetry. The results of measurements showed a significant effect of the ballast layer consolidation on the distribution of stresses under the sleeper. The performed research opens up opportunities for practical improvement of the existing types of track structures and the technology of the ballast layer tamping in terms to provide the optimal conditions for the ballast layer operation.
Improvement of the Method for Standardizing the Duration of Rail Cars Shunting
(НГУ, Дніпро, 2021) Kozachenko, Dmytro M.; Gera, Bogdan V.; Manafov, E. K.; Gorbova, Aleksandra V.; Korobiova, Ruslana G.
ENG: Purpose. To improve the method for calculating the time standard for shunting cars from track to track in order to take into account the local operating conditions of railway stations and railway sidings. Methodology. During the research, the methods of theory of railway operation were used. The problem of calculating the time standard for shunting operation was solved as the problem of searching the optimal division of train set into the car groups to achieve minimal time consumption for shunting operation. Findings. In the course of the study, the methods for calculating the time standards for initial and fi nal operations, as well as movements performed when shunting cars from track to track were improved. It was proved that the minimum time spent on shunting cars from track to track was achieved when the train set was divided into the minimum possible number of parts and the cars were shunted in the longest possible groups and one remaining group. It was also established that with suffi cient accuracy for engineering problems the duration of shunting train set from track to track can be represented by the piecewise linear function of the car number in it. Originality. The work originality consists in improving the method for calculating the time standard for shunting cars from track to track, that, unlike the existing one, takes into account the length limitations of the car groups being shunted from track to track, as well as the actual composition of operations performed in the process of shunting. Practical value. The use of the developed method allows setting time standards for shunting cars from track to track, taking into account the local operating conditions of railway stations and sidings of industrial enterprises. The method also makes it possible to simplify solving problems of searching the optimal order of performing more complex shunting operations, such as sorting cars into several tracks, collecting cars on one track, train formation, and others.
Improving the Dependability Evaluation Technique of a Transport Vehicle
(Kaunas Univ. of Technology, Lithuania, 2020) Babyak, Mykola O.; Neduzha, Larysa O.; Keršys, Robertas
EN: The safety of vehicles depends on the dependabiliti of its elements, which should guarantee the trouble-free operation throughout the entire service life. The concepts of "safety" and "dependabiliti" for the vehicle are inseparable. Therefore, all structural components throughout the entire service life before the onset of the limit state must guarantee trouble-free operation of rolling stock with the installed system of maintenance and repair, i.e. be in working condition as long as possible and perform all necessary functions. Regarding the relevance in predicting the technical condition of a vehicle, authors present improving the dependabiliti evaluation technique of its facility by the value of a safety factor. The impact of actual operating conditions of rolling stock on durability and operability (on the example of a pantograph) is taken into account. The nearest relation between the dependabilitiof a structure and a safety factor and parameters of probability distributions of stresses is determined. Improving the technique can be used to evaluate the dependabiliti of the facility from the viewpoint in the individual prediction of operability and life of the structural elements for the vehicle based on observations over the process of their wear. This will increase the safety and dependabilitiof operation for all complex structures.
Improving the Methods of Estimation of the Unit Train Effectiveness
(Silesian University of Technology, Poland, 2016) Kozachenko, Dmytro M.; Vernigora, Roman V.; Balanov, Volodymyr O.; Sannytskyy, Nazar М.; Berezovy, Nikolay I.; Bolvanovska, Tetiana V.
ENG: Summary. The article presents the results of studies of freight transportation by unit trains. The article is aimed at developing the methods of the efficiency evaluation of unit train dispatch on the basis of full-scale experiments. Duration of the car turnover is a random variable when dispatching the single cars and group cars, as well as when dispatching them as a part of a unit train. The existing methodologies for evaluating the efficiency of unit trains’ make-up are based on the use of calculation methodologies and their results can give significant errors. The work presents a methodology that makes it possible to evaluate the efficiency of unit train shipments based on the processing of results of experimental travels using the methods of mathematical statistics. This approach provides probabilistic estimates of the rolling stock use efficiency for different approaches to the organization of car traffic volumes, as well as establishes the effect for each of the participants in the transportation process.
Improving the Positioning Accuracy of Train on the Approach Section to the Railway Crossing
(Дніпропетровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпропетровськ, 2016) Havryliuk, Volodymyr I.; Voznyak, Oleg M.; Meleshko, V. V.
EN: Purpose. In the paper it is necessary to analyze possibility of improving the positioning accuracy of train on the approach section to crossing for traffic safety control at railway crossings. Methodology. Researches were performed using developed mathematical model, describing dependence of the input impedance of the coded and audio frequency track circuits on a train coordinate at various values of ballast isolation resistances and for all usable frequencies. Findings. The paper presents the developed mathematical model, describing dependence of the input impedance of the coded and audio-frequency track circuits on the train coordinate at various values of ballast isolation resistances and for all frequencies used in track circuits. The relative error determination of train coordinate by input impedance caused by variation of the ballast isolation resistance for the coded track circuits was investigated. The values of relative error determination of train coordinate can achieve up to 40-50 % and these facts do not allow using this method directly for coded track circuits. For short audio frequency track circuits on frequencies of continuous cab signaling (25, 50 Hz) the relative error does not exceed acceptable values, this allow using the examined method for determination of train location on the approach section to railway crossing. Originality. The developed mathematical model allowed determination of the error dependence of train coordinate by using input impedance of the track circuit for coded and audio-frequency track circuits at various frequencies of the signal current and at different ballast isolation resistances. Practical value. The authors propose the method for train location determination on approach section to the crossing, equipped with audio-frequency track circuits, which is a combination of discrete and continuous monitoring of the train location.
Investigation of KPP-5 Rail Fastener Elastic Deformation
(Universiti Malaysia Pahang, Malaysia, 2018) Marcul, Ruslan V.; Nastechik, Nicolai P.; Kovalchuk, Vitalii V.; Hnativ, Yuriy M.
EN: For a long period of operation, a number of shortcomings have been identified in KPP-5 fastener that is mainly due to an intensive decrease of pressing force of the rail on leepers. This leads to the appearance of frequent cases of track displacement and fastening elements failure. To verify such hypothesis, the process of power work of KPP-5 fastener during railway track operation was researched. The technique and practical means of controlling the power work of KPP-5 fastener are developed. The influence of various factors of the rail pressing force on the sleeper is determined. The main influence is conditioned by under-rail wear (50.4%). The obtained results made it possible to formulate recommendations for the improvement of KPP-5 fastener where the methodology and practical means of controlling the power work of KPP-5 fastener were proposed. At the same time, it allows increasing the reliability and safety of the rail track during the entire overhaul period.
Longitudinal Vibrations of Viscoelastic Longitudinally Nonuniform Rod under Power Load Distributed Along its Length
(Lviv Polytechnic National University, Lviv, 2016) Gera, Bogdan V.; Sitarz, Marek; Bolzhelarskyi, Yaroslav V.
EN: In this article, the dynamic behavior of a moving elongated object is simulated using the relations for a viscoelastic rod, which moves at a constant speed under the action of traction force and distributed along its length external forces of resistance. We investigate the change of displacements and internal forces after the sudden application in the rod section of the local force directed longitudinally. The correlations of the initial boundary value problem that describes the dynamic behavior of the rod are written down, and its solution is obtained in the form of a series expansion in terms of eigenfunctions. For a viscoelastic rod consisting of three connected uniform rods, the analysis of wave processes induced by the application to the rod of a sudden concentrated force that resists the motion is carried out. This affects the motion of the rod as a whole, and induces the wave processes, the propagation and reflection of waves on the inner surfaces of joints. The comparison is performed for the behavior of an elastic, piecewise nonuniform rod and a viscoelastic rod with different mechanical characteristics, where the waves during their propagation are damped and smoothed.
Method of Calculation of Temperature Field and Deflected Mode of Bridge Structures in Software Environment NX NASTRAN
(Szcześniak, Warsaw, 2013) Luchko, Josyp; Hnativ, Yuriy M.; Kovalchuk, Vitaliy V.
EN: Abstract: Designs of bridges and overpasses during operation are sustained to complex climatic factors. Study of heat exchange components is an integral part of preparation data for thermal stresses and deformations calculation. Sequence determination of thermal stresses and deformations of bridge structures. Close conditions of the structural elements of modern bridges and overpasses, a variety of their shapes, materials and sizes result in extremely difficult and expensive full- or part-scale investigations. In this regard, there is need to develop and apply various computational approaches that allow relatively in a short time and with little cost to obtain data about engineering structures.
A Model of Transit Freight Distribution on a Railway Network
(The Silesian University of Technology, Katowice, Poland, 2019) Kozachenko, Dmytro M.; Skalozub, Vladyslav V.; Gera, Bogdan V.; Hermaniuk, Yuliia M.; Korobiova, Ruslana G.; Gorbova, Aleksandra V.
ENG: Summary. The peculiarity of the transit freight transportation by rail in international traffic is the fact that while performing transportation, the railway administrations are in competition among themselves. At the same time, the routes of cargo traffic volumes sig- nificantly depend on the conditions of transportation by railways of individual states. The mathematical model for the distribution of transit freight traffic volumes on the railway network, based on the methods of graph theory and game theory, was proposed in this ar- ticle. The developed model enables the evaluation of the possibilities of attracting transit freight traffic volumes by indi by changing the tariff value and transportation conditions.
Multifractal Analysis of the Common Crossing Track-Side Measurements
(Sciendo, Slovakia, 2019) Sysyn, Mykola P.; Izvolt, Libor; Nabochenko, Olga S.; Kovalchuk, Vitalii V.; Sestakova, Janka; Pentsak, Andriy
EN: The deterioration common crossing elements increase the need for the maintenance of crossings and significantly reduce the reliability, availability and safety of railway traffic. The present paper introduces the results of experimental investigation of common crossing monitoring while its deterioration during the lifecycle of crossing. The conventional methods of common crossing condition estimation with time-based features like maximal accelerations, etc. are low appropriate as statistically significant condition indicators. The proposed multifractal analysis enables to extract the significant features from acceleration measurements. The extracted features are fused together with information about the train velocities and longitudinal position of wheels impact with the Lasso regularisation and multivariate linear regression. A ranking of feature importance is done and the redundant features are identified. The developed condition indicator has good correlation to the crossing lifetime and is simple for interpretation.
Obtaining and Investigation of the Conditions of Heat Transfer Through Inhomogeneous Inclusion with Heat Sources
(Національний університет «Львівська політехніка», Львів, 2015) Gera, Bogdan V.; Dmytruk, Veronika A.
EN: The conditions of nonideal heat transfer are obtained for a heat conduction problem of contacting layers through a thin heterogeneous sublayer (inclusion) with acting heat sources (heat sinks). These conditions include both thermal resistances of components of the inclusion and specific powers of heat sources in them. On this basis, the heat conduction problem with nonideal conditions of heat transfer without consideration of inner inclusion is written down. Their use ensures observable features of temperature and heat flux, i.e. the function of temperature and the function of heat flux have a drop when passing through the contact interface. The magnitude of thermal resistance is suggested to be determined by means of more usual for measuring values, e.g. a thermal conductivity coefficient and a thickness of the inclusion. Surface specific heat sources can be set if the values of heat dissipation on the contact boundary are known. From the obtained and generalized heat transfer conditions, the known conditions of nonideal thermal contact can be obtained as particular cases.
One Approach to Quasi-Optimal Control of Direct Current Motor
(IEEE (Institute of Electrical and Electronics Engineers), 2019) Tryputen, Mykola; Kuznetsov, Vitaliy; Serdiuk, Tetiana M.; Kuznetsova, Alisa; Tryputen, Maksym; Babyak, Mykola O.
ENG: The article presents the calculation of the transfer function of the DCM-30-N1-0.2 micromotor DC, obtained a transcendental system of equations for determining the duration of the quasi-optimal control intervals and the dependence of the first control interval on the specified overshoot. The obtained dependence can be used in the engineering methodology for the synthesis of quasi-optimal control and the choice of actuators of the automatic control system.

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