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до 2013 року виходив під назвою "Вісник Дніпропетровського національного університету залізничного транспорту імені академіка В. Лазаряна"

Science and Transport Progress.
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until 2013 appeared under the title "Bulletin of Dnepropetrovsk National University of Railway Transport named after Academician V. Lazaryan"

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Now showing 1 - 6 of 6

Computer Simulation of Dead-End Mine Working Ventilation
(Dnipro National University of Railway Transport named after Academician V. Lazaryan, 2019) Biliaieva, Viktoriia V.; Kirichenko, Pavlo S.; Gunko, Olena Y.; Bondarenko, Iryna O.; Mashykhina, Polina B.; Yakubovska, Zinaida M.
ENG: Purpose. The important problem in the field of ecological safety and industrial safety is providing of normal microclimate in dead-end mine working. In these regions of the mine methane gas can be accumulated and as a result explosion may take place. So, to avoid these accidents it is important to ventilate appropriately dead-end mine working. The purpose of the work is development of quick computing mathematical model to obtain information about dead-end mine working ventilation process. Methodology. The process of dead-end mine working ventilation computing is separated in two stages. At the first stage the velocity flow field is computed in the dead-end mine working. We consider the situation when the suction tube is situated in this region. To solve this problem the fluid dynamics model of inviscid gas flow was used. At the second stage of the computational modeling the convective-diffusive equation of admixture transfer was used. The equation takes into account non-uniform flow field in the dead end mine workings. Findings. The developed numerical model was coded using FORTRAN language. The developed computer code allows to perform numerical experiment to assess the efficiency of suction tube imple-mentation to decrease methane gas concentration in dead-end mine working. Originality. The developed numerical model takes into account physical factors, which are not considered nowadays in the empirical models, which are used for solving the problems of dead-end mine working ventilation. It allows taking into account the geometrical form of the dead-end mine working. Practical value. The developed computer program allows to perform calculations to assess the efficiency of suction system used for the ventilation of the dead-end mine working.
Formation of Estimated Conditions for Life Cycle of Deformation Work of the Railway Track
(Дніпропетровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпропетровськ, 2015) Bondarenko, Iryna O.
ENG: Purpose. The purpose of this research is to substantiate the technical limits of the railway track (under reliability status) for the formation the regulatory framework for reliability and functional safety of the railway track in Ukraine. Methodology. In order to achieve the goal of research analysis methods of the technical states of elements and trackforms that are typical of operation conditions of the railways in Ukraine were used. Findings. Technical states accordance of elements and trackforms to reliability status under existing regulations was defined. These conditions are based on the track assessments in accordance with the dimensional tape results. The status of each element of the track design affects its deformation work, but the rules are still absent that would connect state of track elements with the state of the track by estimation of the dimensional tape. The reasons on which the limits are not set were established. It was found out which researches are necessary to conduct for their installation. Originality. The classification of the reliability state of a railway track for permitted deviation at the track laying and maintenance was developed. The regulation importance the technical states of ballast section and subgrade for the developed classification was established. Practical value. Ukrzaliznytsia (UZ) is a founding member of the Council for Railway Transport of the Commonwealth. This body issued interstate standard State Standard 32192-2013 «Reliability of railway equipment. Basic concepts, terms and definitions». On this basis developed a new interstate standard «Security functional of railway equipment. Terms and definitions». At the same time UZ is a member of the cooperation of railways in International Union of Railway Transport where rules with reliable and safe operation of railways are established in all transport branches. This study will help implement these standards on the railways of Ukraine, improve the efficiency of the information in this sphere, providing mutual understanding and unity of presentation and perception of information, including contractual legal relations of economic agents with public authorities in international scientific and technical, trade and economic relations.
Investigation of the Influence of the Rolling Stock Dynamics on the Intensity of Using the Railway Track Elements
(Дніпровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2019) Bondarenko, Iryna O.; Neduzha, Larysa O.
ENG: Purpose. The main purpose of this work is to research deformability parameters of the railway track under various operating conditions as the initial data for the formation of forced oscillations of rolling stock and the trackform use intensity. Methodology. For the research, an original model of the trackform, described with using the basic concepts of the theory of elasticity and the propagation of elastic waves was developed. Findings. It has been established that the ratio between the intensity of work of elements and the trackform, as criteria for deformability, can be used as the estimated parameters of the functionally safe operation of the track. It can be the basis for the classification of critical track states under which it had to perform work to restore its working capacity in order to ensure the required level of efficiency of use construction during the service life. Originality. Trackform and parameters of the elements of the track superstructure and substructure can be described using the railway tracks deformability behaviour. In the future this conclusion will help to increase the efficiency of the dynamic properties of rolling stock when designing and maintain in readiness the infrastructure while in operation. Practical value. Changes in the regulatory framework of rail transport in recent years provide for the observance of its functional safety, therefore, the question of the need to assess the impact of rolling stock on the way to be regarded as a dynamic process with consideration to the deformability resistance track. This research provides a basis for record of the stiffness of deformation that allows creating the regulatory framework for the functional safety of the railway track in Ukraine.
Numerical Modeling of Air Pollution From Dumps
(Дніпровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2019) Biliaiev, Mykola M.; Rusakova, Tetiana I.; Kalashnikov, I. V.; Bondarenko, Iryna O.; Gunko, Elena Yu.
ENG: Purpose. Rock dumps are long-term sources of air pollution. A significant amount of harmful substances enters the atmosphere. Particularly intense is the pollution of atmospheric air due to dusting dumps. An important task is the development of methods for predicting the dynamics of atmospheric air pollution during the emission of harmful impurities from dumps. When developing methods for predicting the dynamics of air pollution from dumps. It is very important to create a universal model that would allow on a single computing platform to calculate the process of atmospheric air pollution for various impurities that are released from dumps. Another important problem is the choice of the place for optimal placement of future dumps in order to minimize their negative impact on the environment. Methodology. Numerical modeling of the formation of atmospheric pollution zones near rock dumps is based on the application of the equation of turbulent dispersion of an impurity in the atmosphere. To solve the problem of choosing the rational location of the dumps, the conjugate equation is used. Numerical integration is carried out using an implicit difference scheme. Findings. Numerical models are developed. The first numerical model allows one to evaluate the effect of rock dumps on air pollution. The second numerical model allows, on the basis of a one-time calculation, to determine the rational location of the future dump from the point of view of its minimal impact on air pollution. Originality. Two numerical models are proposed that are based on the application of the turbulent diffusion equation and the conjugate equation. These models make it possible to quickly determine the effect of rock dumps on air pollution. The models take into account the convective transport of the pollutant, atmospheric turbulent diffusion, the intensity of the emission of impurities from the dump. Practical value. The developed numerical models are implemented in the form of program codes. These program codes can be used when performing serial calculations on computers of low and medium power, i.e. computer technology, which is available to organizations involved in environmental issues in technologically saturated regions. When carrying out calculations based on the constructed numerical models, typical initial data are used regarding the intensity of the emission of impurities from dumps, weather conditions characteristic of a specific region of the country.
Prediction of Atmosphere Pollution in Case of Emissions From Main Mine Fans
(Dnipro National University of Railway Transport named after Academician V. Lazaryan, 2019) Biliaiev, Mykola M.; Bondarenko, Iryna O.; Rusakova, Tetiana I.; Shynkarenko, Viktor I.; Gabrіnets, Volodymyr O.
ENG: Purpose. Emissions from mine ventilation system can create intensive atmosphere air pollution. As a rule, a huge amount of dust from mine fan enters atmosphere low layers. An important task is the development of methods to assess levels of the atmosphere pollution near mines and settlements. To solve this problem it is important to have physically proved mathematical models. Nowadays to predict the atmosphere pollution near settlements which are effected by mine fan the empirical model OND–86 is used. This model does not take into account many important physical factors. So, the purpose of this study is the development of quick computing mathematical model to predict the atmosphere pollution in case of dust emissions from mine fan. Methodology. To predict levels of the atmosphere pollution in case of mine fan work 3D equation of dust convective – diffusive flow was used. This equation takes into account gravity fallout, wind velocity, atmosphere turbulent diffusion, location of dust emission source. To sole modeling equation the implicit difference scheme of splitting was used. Findings. Developed mathematical model allows quick prediction of the level of atmosphere pollution in case of dust emissions from mine ventilation fan. The models allow to obtain zones of contamination near settlements which are situated in vicinity of mine. Originality. The developed mathematical model takes into account a number of physical factors, which at the present time are not considered on the days when prediction of the atmosphere pollution in settlements near mine is carried out. Practical value. On the basis of the developed mathematical model program code was created. This code can be used for evaluation of atmosphere pollution in settlements which are effected mine fan emissions.
The Problem of a Lack of Material Behaviour Data For Risk Assessment
(Дніпровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2020) Bondarenko, Iryna O.; Nеduzha, Larysa O.
ENG: Purpose. The main purpose of this work is to provide theoretical support for the need to expand data on changes in the material behaviour under dynamic loads when railway track risk assessment over time due to railway track elements deformability. Methodology. For the research, an original model of railway track design described using the original method based on the ability of elastic waves to propagate energy of power pulses in space and time, as well as a model describing materials as discrete substances were used. Findings. It has been established that the properties of the material affect the deformability of the elements and the design of the railway track; the main parameter in the study of deformability processes is time; material, as a substance, consists of atoms and molecules, and therefore is not continuous; internal physical processes determine changes in the behaviour of the material of an element. Originality. It has been proposed to develop classifications of changes in the physical properties of materi-als according to the probability of irreversible deformations and the impossibility of deformations, as well as classi-fications of changes in the mechanical properties of materials according to the probability of the defect appearance and changing the material structure. Practical value. The ability to simulate analytically any physical processes occurring inside elements due to the proposed method allows combining the influence of mechanical and physical effects into a single calculation. This enables to assess the probability of appearing defects in elements under certain dynamic loads when assessing the railway track risk over time due to railway track elements deformability.