Dnipropetrovsk National University of Railway Transport named after Academician V. Lazaryan

About: Dnipropetrovsk National University of Railway Transport named after Academician V. Lazaryan is a education organization based out in Dnipro, Ukraine. It is known for research contribution in the topics: Track (rail transport) & Bogie. The organization has 736 authors who have published 655 publications receiving 1468 citations. The organization is also known as: Institute of Railway Transport Engineers.

The choice of parameters and criteria for automatization of control tone track circuits

Abstract: Based on the analysis of existing methods of checking the tonal frequency track circuits, the choice of parameters and options for check automation of tonal frequency track circuits is conducted.

The use of management accounting in railway transport

Abstract: The article is devoted to distribution of general operational costs, which is an important aspect of the expenditure analysis for managerial decision-making.

Mathematical model development of heat and mass exchange processes in the outdoor swimming pool

Abstract: Purpose. Currently exploitation of outdoor swimming pools is often not cost-effective and, despite of their relevance, such pools are closed in large quantities. At this time there is no the whole mathematical model which would allow assessing qualitatively the effect of energy-saving measures. The aim of this work is to develop a mathematical model of heat and mass exchange processes for calculating basic heat and mass losses that occur during its exploitation. Methodology. The method for determination of heat and mass loses based on the theory of similarity criteria equations is used. Findings. The main types of heat and mass losses of outdoor pool were analyzed. The most significant types were allocated and mathematically described. Namely: by evaporation of water from the surface of the pool, by natural and forced convection, by radiation to the environment, heat consumption for water heating. Originality. The mathematical model of heat and mass exchange process of the outdoor swimming pool was developed, which allows calculating the basic heat and mass loses that occur during its exploitation. Practical value. The method of determining heat and mass loses of outdoor swimming pool as a software system was developed and implemented. It is based on the mathematical model proposed by the authors. This method can be used for the conceptual design of energy-efficient structures of outdoor pools, to assess their use of energy-intensive and selecting the optimum energy-saving measures. A further step in research in this area is the experimental validation of the method of calculation of heat losses in outdoor swimming pools with its use as an example the pool of Dnipropetrovsk National University of Railway Transport named after Academician V. Lazaryan. The outdoor pool, with water heating-up from the boiler room of the university, is operated year-round.

Investigation of admixture sedimentation in the horizontal settler

Abstract: Purpose Sedimentation by gravity is the most common and extensively applied treatment process for the removal of solids from water and wastewater and it has been used for over one hundred years Sedimentation tanks are one of the major parts of a treatment plant especially in purification of turbid flows Horizontal settlers are mainly used for purification of high quantity of water In these tanks, the low speed turbid water will flow through the length of the tank and suspended particle have enough time to settle Finding new and useful methods for calculating and increasing hydraulic efficiency of horizontal settlers is the objective of many theoretical, experimental and numerical studies But currently used models and methods in Ukraine do not allow taking into account geometrical form and various design features In this paper the numerical model was developed to evaluate the effectiveness of horizontal settler with modified structure Methodology Numerical m odel is based on: 1) equation of viscous fluid dynamics; 2) mass transfer equation For numerical simulation the finite difference schemes are used The numerical calculation is carried out on a rectangular grid For the formation of the computational domain markers are used Findings The model allows obtaining the purification process in the settler with different form and different configuration of baffles Originality A new approach to investigate the mass transfer process in horizontal settler was proposed This approach is based on the developed CFD model The fluid dynamics model was used for the numerical investigation of flows and waste waters purification To investigate influence of baffles on settler efficiency physical experiment was carried out Practical value The developed model has more capacity than the existing models in Ukraine The developed model allows computing quickly the efficiency of water purification in settlers The model is not computationally expensive Calculation time of one variant of the problem takes few minutes

Studying of the Power Modes in the Traction Line for Ensuring the High-speed Traffic

Abstract: The object of research is the power regimes in traction power systems for both centralized and distributed power when introducing high-speed traffic. The introduction of high-speed traffic on electrified railways of Ukraine has begun a number of restrictions in the applied system of traction power supply of centralized power supply. These include not only the impossibility of providing the necessary voltage level of 2.9 kV, but also the low efficiency of the aggregate power of traction substations. In this case, the applied traction power system does not allow to provide the necessary level of specific power in the traction network. Applicable technical means and measures to strengthen the traction network do not allow, in most cases, to provide regulatory requirements for the organization of high-speed traffic. An analysis of modern research shows that overcoming these disadvantages is possible due to the application of a distributed power supply system to the traction network. To date, sufficient options have been developed for constructing such systems, but in this paper, as an alternative, a system was considered with the distribution of the aggregate power available in the system of centralized power in the inter-substation zone. At the same time it was reasonable to reduce the power of the traction substation to the level of 10 MW. During the study of power regimes in comparable traction power systems, the results of experimental studies and simulation modeling of the operating modes of the comparable systems were used. Calculations were taken into account not only the specifics of the traction load, but also its impact on the load capacity of the contact suspension. As a result of this approach, it has been shown that the distributed traction power system allows to fulfill the regulatory requirements for providing high-speed traffic. With its application, the consumption of electric energy for traction of trains is reduced by 40 %, the specific power of traction network increases by 90 %, and the load factor of traction substations – by 60 %. The proposed innovative approach to providing the necessary power mode in the traction line for the organization of high-speed traffic allows to preserve the existing infrastructure on existing electrified section of direct current. This approach allows the application of various types of electric rolling stock and provides the required capacity of the railways.