bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reducing of coal dust release from train wagon with barrier
Authors: Biliaiev M M , Biliaieva V V , Kozachyna V A , Berlov O V , Oladipo M O , Kirichenko P S 
Published: December 2020

Abstract
Intensive environment pollution takes place during coal transportation in open wagons. Emission of coal dust from the coal wagons cause contamination of atmosphere and territory adjacent to the railway track. Different ways to reduce coal dust emission from the wagon are used in the world. Unfortunately, in Ukraine, this problem is far from solution and there is no serious research work in this field. The aim of this work was laboratory study of coal dust emission from the wagon model which had different barriers installed on the wagon. Laboratory experiments were carried for coal wagon without barrier and for coal wagon which had barriers of two types. Barrier of the first type had downwind wing. Barrier of the second type had upwind wing. The contamination zones, concentration near the model were studied. The obtained results illustrate that installation of barriers influence intensity of transport corridor contamination. Also a numerical model was developed to estimate wind flow and coal dust dispersion from the coal wagon. Equation of potential flow and equation of coal dust dispersion were used. Implicit difference schemes of splitting were used for numerical simulation of governing equations. Results of numerical experiment, which were performed, are presented.
The results of brake tests of the DPKr-3 diesel train
Authors: Dovhaniuk S , Shaposhnyk V , Shykunov O , Shatunov A , Visloguzov V 
Published: December 2020

AbstractJSC “Ukrzaliznytsia” purchased the first of three planned regional three-car (two main motor cars and one intermediate) diesel train DPKr-3 manufactured by PJSC “Kryukovsky railway car building works”. To confirm the declared characteristics and safety indicators of the DPKr-3 diesel train, specialists department of Cars of Dnipro National University of Railway Transport named after Academician V. Lazaryan conducted complex certification tests, which confirmed the compliance of the stated parameters. One of the points of the Terms of Reference was to determine the brake pressure of the linings per 100 weight of the train in terms of cast iron brake pads. For this purpose, according to the methodology adopted in the territory of the former CIS, force sensors, which were installed in the tick mechanisms instead of the brake linings, measured the magnitudes of the forces of pressing the brake linings on the disks. However, during the tests it was found out that the current standards for calculating the provision of train brakes cannot be applied to modern rolling stock. It is recommended for rolling stock where the use of brake pads, and even more cast iron, is not provided by the design, to develop normative documents that would determine the standards for brakes by the results of calculations and tests.
Optimal Control Method of High-Voltage Frequency Converters with Damaged Cells
Authors: Busher V , Chornyi O , Glazeva O , Kuznetsov V G , Tytiuk V , Tryputen M 
Published: December 2020

Abstract
Application of high-voltage frequency converters is one of the most prospective trends in the development of current powerful electric drives, i.e. in high-speed trains. In terms of such converters, a multilevel cascaded H-bridge converter is becoming the most widespread one owing to its increased reliability, survival in terms of one or more damaged cells, and quick repairability due to its modular structure. The research proposes a control method, which provides maximum possible linear voltage in case of one or several damaged cells owing to the shift of zero point and turning of phase voltages. It is also demonstrated how turning angles of phase voltages should be set to preserve spatial position of the linear voltage vectors which provides the least complicated electromagnetic transients in terms of nominal rotation frequency; in case of low or middle frequencies, damage of the cells may have no effect on the motor operation. Fast algorithm to calculate turning points of phase voltages is proposed; the algorithm may be applied in the industrial microprocessor control systems. Algorithm of the operations, which provides implementation of the method, is described.
Mathematical modeling of shock wave interaction with wagon
Authors: Khrutch V K , Biliaiev M M , Kozachyna V A , Berlov O V , Kirichenko P S , Biliaieva V V 
Published: December 2020

Abstract
In case of some accidents on railways there may be situations when the shock wave appears and interacts with different objects on the railway (wagons, cargo, buildings etc.). In these cases it is necessary to predict the possible effect of shock wave diffraction on the different objects. Study of these problems on the basis of physical experiments (laboratory experiment or field experiment) demand expensive and unique experimental facility. In some cases physical experiment can’t be set. That is why mathematical simulation plays the important role in solving problem connected with shock wave propagation. For practice it is necessary to have predictive quick computing mathematical models which allow to perform numerical experiment on the basis of non-powerful computers. Now, in Ukraine, there is a real deficit of mathematical models which allow to compute quickly shock wave interaction with different objects. The aim of this work was development of quick computing numerical model to simulate shock wave propagation and its interaction with the wagons. The model is based on the numerical integration of Euler equations which are written in integral form. To solve modeling equations difference scheme of splitting was used. Results of numerical modeling are presented.
Energy efficiency of heat tests for traction electric machines
Authors: Afanasov A M , Shapovalov O S , Holik S N , Arpul S V , Bilukhin D S 
Published: December 2020

AbstractThe article discusses one of the options to reduce the electricity consumption for the carry out acceptance of post-repair tests of traction electric machines. Heating tests of traction electric machines at the mutual load stand are the most energy-intensive part of the entire test program. Energy consumption for this type of test can be reduced, for this, an analysis of thermal processes in the windings of traction electric machines during their heating test was given. The energy efficiency coefficient of the mutual load system is formulated. The energy efficiency coefficient for the traction electric machine NB-406 is calculated. The calculation results showed that with an increase in the test current by 30%, the total losses in the motor windings decrease by about one and a half times, while the test time decreases by almost three times. An increase in test current and a decrease in test time do not reduce the quality of the test, and the results obtained. A methodology for assessing the energy efficiency of heating tests is proposed. It can be applied at test sites of depots, as well as repair plants. This will reduce the material costs of testing, without compromising the quality of the tests themselves.
Research of the modern absorbing apparatus power characteristics influence on the freight train inter-car forces
Authors: Shimanovsky A O , Sakharau P A , Kuzniatsova M G 
Published: December 2020

Abstract
A mathematical model of the inter-car connections used in the long and heavy train is presented. It takes into account the elastic-frictional properties of absorbing devices and gaps in automatic coupler devices connecting the train cars. There are demonstrated the calculation results of a homogeneous train motion along a straight horizontal track section at such non-steady modes as at starting, braking by the locomotive electrodynamic brakes and passing along a track profile section of a complex shape. A comparative assessment of the influence of the kind of the absorbing devices power characteristic on the maximal longitudinal forces arising in the train inter-car connections is carried out using the MSC ADAMS engineering software package. Transients with a smooth and sharp change in traction and braking forces are considered. Based on the obtained results, the main positive and negative properties of rigid, linear and soft power characteristics of the automatic couplers’ absorbing devices used on the railway rolling stock are determined. The results of performed computer simulation can be applied to the sphere of design and modernization of absorbing devices of automatic couplers and to the process of composition of various types of cars in trains of any length and weight.
Stand for accelerated tests of rail vehicles wheelsets
Authors: Raksha S , Anofriev P , Kuropiatnyk O 
Published: December 2020

Abstract
Tests and research can be greatly accelerated by applying a multi-point load to the test wheel. The aim of this work is to substantiate rational parameters of the stand for accelerated life tests of railway wheelsets, in which a multi-point load applies to the rolling surface of the test wheel. On the basis of the laws of the theory of elasticity, we performed analytical calculations of the contact stresses created by the rolling bodies of the load mechanism of the test stand. Research has shown that the dependence of the contact stresses on the wheel rolling surface on the ball’s diameter is nonlinear. The decrease in stress is due to an increase in the contact area. We obtained the analytical and graphical dependencies, which make it possible to evaluate the influence of the parameters of the stand for accelerated life tests of railway wheelsets on contact stresses on the wheel rolling surface, taking into account the shape and dimensions of this surface. The authors have proposed a stand design for accelerated life tests of railway wheelsets. The use of a stand with the parameters justified in this work will reduce the test duration by 10-15 times.
Theory development for determination of rational parameters of the capacitive energy storage for a metro train
Authors: Sulym A O 
Published: December 2020

Abstract
In the article a comparative analysis of existing methodologies and approaches on the parameters determination of the capacitive energy storages for a metro train with energy recovery systems was performed, disadvantages of each of them were determined. A complex approach for estimation of the on-board capacitive energy storage parameters was proposed; the point of approach consists in determination of the rational power and energy capacity for two parameters of the storage system at once – mass and payback period. The complex approach is based on theoretical researches, which require simulation of the metro train equipped with recuperation system operation by mean of developed software. The objective function was represented and boundary values for the power and energy capacity during determination of the rational parameters of the on-board capacitive energy storage using a complex approach were specified. The recuperation system with rational parameters of the on-board capacitive energy storage for specified service conditions in Public Utility Company “Kyiv Metropolitan” and chosen research metro train was specified. Amount of energy stored due to the installation of the energy storage system with rational parameters was estimated.
A new method to create of the plane section standards of grain metal structures
Authors: Danilenko T 
Published: December 2020

Abstract
A new method to create of the plane section standards of grain metal structures with a previously known size distribution of 3D grains is proposed. A quantitative analysis of G3, G4, G5 indices of the standard ISO 643:2012 was performed. The stereological modeling method taking into account the polyhedral shape of 3D grains was used to create new versions of plane section standards. Versions of 3D grains structures as the diameter size distributions of 3D grains, plane sections of which correspond to the main quantitative characteristics of existing G3, G4, G5 indices have been created. It was shown that these versions should contain 3D grain more than 1.5 times the mean diameter of the corresponding plane sections. Choosing the diameter size distributions of 3D grains, necessary for the standard, its possible to create a visual index as a picture, as it done on the existing standard, and also to give the parameters of 3D structure, plane section of which corresponds to this standard. Using a new approach to creating standards will increase the accuracy of the grain structure parameters determining.
Feasibility study of using permanent magnets as indirect temperature monitor in irradiation capsule of nuclear research reactor
Authors: Saurav Suman , Muthuganesh M. , Chaurasia P. K. , Murugan S. 
Published: December 2020

Abstract
In sodium cooled nuclear fast reactors, materials used for fuel cladding and structural components can undergo significant physical and dimensional changes due to exposure to high energy neutrons. At high temperature and radiation conditions prevailing in the nuclear reactor, material properties change considerably. Information about the temperature of exposure during specimen irradiation in a nuclear reactor is important since the temperature is having a strong influence on the mechanical and physical properties of materials. A proper evaluation of the effects due to radiation on materials needs a precise knowledge of the irradiation temperature. Many times, standard techniques for measuring temperature are not practicable in reactors due to the availability of limited instrumented positions. Therefore, the use of small-sized indirect temperature monitors such as melt wires, permanent magnets, etc. which can be incorporated along with the samples and examined after the irradiation are preferred. In the present study, permanent magnets of neodymium grade N38 and N38SHX of different sizes have been studied for their possible use as an indirect temperature monitor. The study was carried out first for their compatibility with sodium since the monitor will be exposed to sodium during irradiation experiments in fast reactors, and then by exposing to different temperatures in an electrical furnace for the determination of Curie point to study the feasibility of using these materials as indirect temperature monitors. Since the material loses its magnetic properties when the temperature of exposure exceeds the Curie point, by using a series of magnets having progressively increasing curie points, the temperature of exposure can be determined by testing these magnets for the retention of their magnetic properties. Specifically, since there is variation in the Curie temperature as reported in the literature, the experimental method was developed to determine the Curie temperature accurately. This paper discusses the details of the experiments carried out in our laboratory and the results obtained from these studies.
Theoretical and experimental modal analysis of centrifugal pump radial flow impeller
Authors: Oza M N , Shah D S 
Published: December 2020

Abstract
Modal analysis is extensively used to identify the dynamic properties of a structure in terms of the dynamic characteristics: natural frequency, damping factor and mode shape. In this research, modal analysis has been carried out on a radial flow impeller of a centrifugal pump. The 3-D model of the impeller was built in CAD software Creo Parametric 1.0 from a 2-D drawing and that model was imported in FEA software package ANSYS for conducting modal analysis. The model was meshed effectively using SOLID187 elements. The first twenty natural frequency and mode shapes were extracted and nodal diameter was identified for each mode shape. The experimental modal analysis was conducted using impact hammer and the first twenty natural frequencies were identified using FFT analyzer. The natural frequencies of both the methods were compared and it was found that there is a good agreement between these results, thus the FE model is validated. The results are discussed and conclusions drawn.
Experimental investigation on the mechanical properties of wood sawdust and plaster of paris reinforced composite
Authors: Singh Avinash , Muniappan A 
Published: December 2020

Abstract
In this work the wood saw dust and plaster of paris have been reinforced to form a new composite material. The materials which have been used are wood saw dust and plaster of paris. Wood saw dust is a derivative of several operations on wood such as drilling, routing, sanding, milling, sawing, planning etc. and plaster of paris is made from gypsum. Gypsum is heated at 373 K in a furnace to lose some water content and thus POP (plaster of paris) is formed. Both materials are mixed together with the help of water to form a paste and are freezed at 0°C for 24 hours. And three different samples are made by varying the ratio of sawdust and plaster of paris. The samples are obtained in the 15cm x 15cm x 3.5cm dimensions by using a plastic box and is given in the laboratory for testing various properties such as density, ash content, hardness, compression load, hardness at -40°C etc. Three different samples are in the ratios (WSD: POP): 3:1, 1:1, 1:3 are obtained. Out of three the third sample gives the best result and can be used as a construction material in cold places.
Design of reduced dipole yagi – Uda antenna
Authors: Muthu Kannan P. , Reji M. , Swaminathan R. 
Published: December 2020

Abstract
This work provides design and analysis of a dipole antenna whose height is reduced. Any Dipole antenna can be designed with λ/2 height. A half wave dipole is formed with ‘λ/2’ height to get desirable characteristics of dipole antenna. Minimizing antenna height is always a desirable in antenna design. Hence, an attempt is made in this work to reduce the height of a dipole and as an application, Yagi-Uda antenna is constructed using this reduced dipole and optimized for better gain. The results are discussed in detail.
Influence of nano SiO2 in cement mortar using taguchi analysis
Authors: Vasanthi P , Senthil Selvan S 
Published: December 2020

Abstract
In this research, optimization technique was employed to optimize the nano SiO2 in cement mortar preparation by using Taguchi-technique. The main aim of this present investigation is to find the optimal input variables like nano SiO2, w/c ratio and plasticizer to achieve cement mortar with high compressive strength and low water absorption percentage. When the input variables are more than one Taguchi - technique approach is a best method since it may give difference set of optimum level for each response. It is found that the addition of nano SiO2, in cement mortar influenced high compressive strength with lower water absorption percentage. According to analysis nano-silica of 2wt. %, w/c ratio of 0.5 and plasticizer of 1wt. % (A2, B3 and C2) is found to be producing highest compression strength of 51.45MPa and lower water absorption percentage of 2.95.
Development and studies of new rolling screw-type mechanisms
Authors: Blinov D S , Morozov M I 
Published: December 2020

Abstract
One of the tendencies in mechanical engineering is the transition from sliding friction to rolling friction in part joints moving under load, motor assemblies and machinery. For the present time, planetary roller screws (PRS), which are rolling mechanisms, possess the biggest potential as converters of rotational motion to linear motion. However production of high-precision parts for PRS requires special expensive equipment. The emerging world tendency for reduction of technological costs is to develop nutless roller screws (NRS), which is the most complex PRS part to manufacture. Its production requires an additional machine tool or a universal grinding machine for external and internal grinding. The new rolling NRS has been developed in line with this tendency. This paper focuses on the design and operation of the mechanism and on theoretical studies. A test model and a testing rig have been developed to confirm the results of the theoretical studies and to determine operation parameters of the new NRS. The experiments showed that the newly developed NRS loses to PRS in some parameters, while outperforming it in other. It is also simpler and cheaper to produce and after additional studies and tests rational applications for the newly developed NRS can be found.
Diagnostics of dissipative characteristics of friction damper
Authors: Chernyshev S L , Kolesnikov V I , Vermel V D , Ozyabkin A L , Kolesnikov I V , Koryakin A N 
Published: December 2020

Abstract
The aim of our study was to broaden current knowledge of characteristics of friction damper that acts to dissipate the energy of small translational oscillations in friction pairs and to convert it into significant angular shaft movements. We have devised a novel methodology to evaluate elastic-dissipative characteristics of the damper, which provides real-time identification of the stability of these characteristics, as well as running-in periods, stable operation, and catastrophic wear. It is shown that plan bearings made of antifriction self-lubricating organic-fiber composite are more effective than plain bearings made of metal-fluoroplastic tape since their use causes less high-frequency noises that affect the quality of transient response.
Modelingof stress-strain state of a pneumatic tire in Abaqus software at stationary rolling
Authors: Korolev P V , Shilov M A , Maslov L B , Fomin S V 
Published: December 2020

Abstract
The paper presents a step-by-step development of a finite element model of stationary rolling of a radial automobile tire on a surface, where friction is taken into account. The method of finite element modeling (FEM) is used to determine the influence of the method of setting the rolling of a pneumatic tire on its performance properties. The authors come to the conclusions about the advisability of using various methods for creating models of pneumatic tires and give recommendations for optimization of the numerical experiment.
On the prospects of research in the field of evaluation and reduction of mining machines elements wear
Authors: Pobegailo P A , Gadolina I V , Gustov Ju A 
Published: December 2020

Abstract
In this paper, the authors present some considerations on how to develop studies of wear (wear resistance) of mining machines for open-pit mining. First, the need to continue research aimed at adapting the A.K. Reisch’s approach was noted to clarify and improve the empirical formula to assess the wear rate of elements of mining and road machines. Secondly, it is planned to deepen research to assess the correlations between the properties of materials used in mining engineering and characteristics of their wear resistance. Thirdly, the problem of wear of elements of mining machines is considered from the standpoint of managing the phenomenon of wear. For this, the A.K. Reisch’s empirical formula can be used, and the optimization problem formulated in a general form, which is reduced to maximizing the productivity of the machine with restrictions on the rate of wear of its elements and the operating costs. Fourth, the relationship between the problem of managing the phenomenon of wear and the dynamics of mining machines is noted. Some of these researches are illustrated by examples of a qualitative nature.
Evaluation of the influence of lubricant quality on dynamic performance and resource of involute gears
Authors: Polyakov S A , Kuleshova E M , Kuksenova L I , Medovshchikov A V 
Published: December 2020

Abstract
The article deals with the relationship between the occurrence of self-oscillations and the wear process in involute gears. The dependence of the amplitude of the torque fluctuations on the high-speed shaft of the involute gears on the type of lubricant is presented. The calculation of the transmission service life is given, taking into account the rate of growth of the dynamic coefficient.