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The article explores the modeling of the interaction between the pantograph and the catenary, which is a relevant task in the development and optimization of current collection systems. The subject of the article is the modeling of the catenary, with finite element models and lumped parameter models being the most widely used approaches. Their key characteristics are highlighted: finite element models offer high accuracy but require significant computational resources, whereas lumped parameter models allow for a quicker assessment of interactions but have limitations due to their simplified representation of physical processes. The aim of this study is to improve the accuracy of modeling the interaction between pantographs and the catenary using lumped parameter models. As part of the research, an improved catenary model is proposed, in which the lumped mass is replaced with an inerter. This modification eliminates the issue of forced oscillations and enhances the accuracy of system dynamics modeling. The proposed model is implemented in MATLAB Simulink, and its validity is confirmed through correlation analysis, demonstrating better agreement between the calculated and experimental data compared to existing models. The obtained results show that the proposed approach allows for a more accurate simulation of the interaction between the pantograph and the catenary, making it a promising solution for use in the design and optimization of current collection systems in railway transport.

An increase in the speeds of the electric rolling stock has an impact on the energy indicators of the operation of the traction power supply system. One of the technical solutions to the task of equalizing the traction load schedule to reduce voltage losses in the contact network is the use of electricity storage systems. The article presents the results of simulation modeling, which allow us to estimate the change in the energy indicators of an electric train with an increase in movement speeds for conditions of a single electric train following a section. According to the results of traction calculations, the influence of the voltage level on the electric train current collector on the technical speed is shown, the deviation of which for the typical voltage values in high-speed traffic is about 1%. For the selected section of rapid movement and technical speeds, the voltage level for traction calculations is justified. The dependences of the change in the average values of the load and the technical speed with an increase in the maximum speed up to 250 km/h are determined. Statistical estimates for the voltage on the pantograph of the Velaro RUS electric train are determined. The influence of the energy intensity of the onboard storage system with the corresponding charging characteristic on the reduction of maximum currents is shown. Dependences are obtained for the voltage drop on the electric train current collectors with an increase in movement speeds. The assessment of the maximum energy intensity of storage devices for the most severe operating conditions with a single electric train track on the site was carried out. These results allow us to determine the prospects for improving the method of calculating energy indicators and the use of accumulation systems in areas of rapid movement as on-board systems and compare their effectiveness with stationary systems based on simulation modeling, in which various control algorithms are implemented.

In the article the paper considers mathematical modeling of fuel equipment of high pressure and regulator of the rotation frequency of the crankshaft of the diesel engine. Analysis of factors affecting fuel equipment, mathematical modelling of the process of fuel into the cylinders, as well as mathematically describes the speed control of the crankshaft of the diesel diesel engine. Joint mathematical model of fuel equipment and rotation speed regulator. Presented algorithm and program calculation process the fuel feed to the cylinders of a diesel engine with a light hydraulic characteristics of generalized elements of fuel equipment and provision of the Executive mechanism of the regulator of the rotation frequency of the crankshaft of the diesel engine. In the work used mathematical and simulation, system analysis methods, the comparative method, methods of theoretical knowledge (formalisation), common logical methods and techniques of research (analysis, synthesis, classification, analogy ).

In paper results researches of interacting of devices of a current collection of monorail transport are resulted. Negative aftereffects of a current collection are analyzed: acoustical noise, radio interferences and light irradiation at a sparking, deterioration of contact elements.

The article deals with theoretical and applied problems of ultrasonic cleaning of parts of rolling stock during the repair. Marked by features of ultrasonic influences in the bath with the limited sizes and the results of the simulation with the use of package Mathcad. Given the results of specific applications.

Annotaion. The relevance of carrying out research works on improving the regulatory and methodological base in the development of promising railroad rolling stock structures with the use of new structural materials with nonlinear properties during deformation (physical nonlinearity) is substantiated in the work. The possibility of using the finite element method (FEM) procedure for creating such constructions is considered. Dependence of stresses on deformations is approximated by a cubic parabola. This made it possible to obtain generalizations of the well-known relations and algorithms of the classical theory of FEM with a nonlinear relationship between stresses and deformations. The proposed technique was tested in the evaluation of the stress-strain state (SSS) of an aluminum gondola car under various standard loads according to the 1st design mode. The effect of physical nonlinearity on the SSS of a spiral beam of a freight gondola car of aluminum alloy AMg6 was estimated. The calculation of the stresses generated by the action of a longitudinal force with eccentricity shows that the stresses in the nonlinear approximation are 13% lower than the corresponding stress values obtained by calculation in the linear theory. The results obtained can be recommended for the development of pilot projects of new structures optimized for weight and strength characteristics.

The purpose of this work is to determine the causes of cracks in the frame of traction motors of electric locomotives. An analysis of the statistics of detecting cracks in the frame of NB-514 traction motors at the Eastern testing area is presented, showing that every third frame in operation has cracks. The method of mathematical modeling on a computer with the use of FEM was used. It is noted that carrying out measurements in the crack initiation zone by the tensometric method is practically impossible due to the geometry of the frame. The results of mathematical modeling of mechanical stresses arising in the frame of the NB-514 traction motor during its uneven heating to temperatures characteristic of the hourly mode of operation of the traction motor are considered. It is shown that mechanical stresses arising only due to the temperature difference between the ambient air and the windings of the main and additional poles of the traction motor can reach 100 MPa. Variants of changing the design of the ventilation windows of the frame are proposed to reduce the magnitude of temperature stresses with a constant area of the ventilation openings. When correcting the shape of the ventilation windows of the traction motor frame, these voltages can be reduced to 76 MPa. It was concluded that one of the main reasons for the formation of cracks in the frame of traction motors are cyclically repeating temperature stresses, which is especially important for electric locomotives operating on mountain pass sections in the pushing mode. It is noted that the appearance of mechanical stresses in the backbone of the traction motor also depends on vibrations arising from the path and operation of the gear train, as well as on the variable part of the magnetic field of the motor, which are not currently studied in detail.

The article is devoted to the research of the of wind load effect on the aerodynamic component to the movement of a freight train. These findings contribute to a better understanding of the impact of aerodynamic resistance on the consumption of fuel and energy resources (FER) on train traction. The article shows the high significance of this problem for Joint Stock Company Russian Railways (RZD JSC). The conclusions were drawn from the analysis of statistical data on the routes of locomotive drivers, working on the Pallasovka-Verkhniy Baskunchak section, which is undergone to wind loads. The SOLIDWORKS application was used to design a train with a locomotive and gondola cars coupled on an embankment, and SOLIDWORKS Flow Simulation plug-in was used to simulate wind load, different in speed, varying from 0 to 90º. The values of the force of aerodynamic resistance to movement for the train as a whole and for each unit of the rolling stock separately were obtained. Using the methods of the theory of train traction, the influence of aerodynamic drag on fuel consumption for traction has been assessed. Based on the obtained values of the aerodynamic drag forces and patterns of air flow distribution, conclusions were drawn about the effect of loading a gondola car on an increase in traffic resistance. Conclusions are drawn about the effect of wind load on each unit of rolling stock in the train. It was found that when the wind is directed at an angle to the axis of the path, the force of the wind effect increases, compared with the case when the angle between the axis of the path and the velocity vector is zero. The experimental data on the increase in resistance from the wind load are confirmed by theoretical calculation, as well as practical processing of routes machinists. This article demonstrates the need for a separate regulation of fuel and energy resources in the event of wind loads, and may be useful in further detailed study of the aerodynamic drag of freight trains.

Features of the methods of calculation of a braking distance of the train applied now are considered. The main shortcomings of the most widespread method of definition of a braking distance on speed intervals are shown. Authors offered the new method of calculation allowing to consider critical parameters of process of braking (speed of a brake wave; character of an indicator diagram of the brake cylinder and mode of a brake; the actual initial speed for calculation of a way of action of brakes of the train). For verification of the offered method computer modeling is executed and the analysis of results of the different methods of calculation of braking length received at application is carried out. The new method allows to make calculation of braking length of the rolling stock more precisely.

The article considers phenomenological and modelling approach to researching of interaction of a deformable wheel and a plane of support, their advantages and disadvantages are mentioned. In the context of phenomenological approach the five methods of locomotive tangent tractive force calculation were considered. There certainly must be pseudo-creeping to let locomotive tangent tractive force do work and change the kinetic energy of a train in the point of wheel and rail contact. Locomotive tractive force experts calculate the power as product of the locomotive tangent tractive force and the velocity of translational motion of a train, although in fact the velocity of the point of force application must be assumed. It is applied to a wheel pair, then the velocity of this point must be used to calculate the locomotive power. According to this fact the locomotive power is found several tens of times reduced.

Method of construction of mathematical models is offered for mechanical systems with additional feedback ties which formed of lever mechanisms of different kinds. It shown that mathematical models can be get by simplifying more complicated system in which lever ties are realized of rigid body with fixed pivot point. Lever ties at the preparation of a model formally appear at decrease inertial moment of intermediate rigid body to very small values. It shown that mechanical oscillation system can be reduced to equivalent scheme which matches estimation scheme of chain type. Equivalent estimation schemes can to differ of various kinds of between-partial ties. Possibilities of using quasi-springs in equivalent estimation schemes are offered and justified. These complicated compositions consist of elastical elements which interconnected of lever mechanisms. Coerced stiffness’s of quasi-springs defined on rules of transformation of structural mathematical models. Base of mathematical modeling is using method of transformation of Laplas with following construction of equivalent in dynamical attitude of structural schemes of automation control systems. Analytical ratios are given. They characterize possibilities of special dynamical regimes.

The article studies comparing the effectiveness of using thermoradiation and convective drying methods insulation windings of electrical machines of traction rolling stock, impregnated with various modern varnishes and compounds at their factory and depot repair. Objective factors in the comparison methods are parameters such as temperature class, electric strength and cementing capacity. The author substantiates advantage thermoradiation method over convective.

The reasons of a case-type vibration in the frictionless bearings in the assembled machine are studied. The method of identification of the radial clearances in the bearings without disassembling is suggested on the basis of the conducted measurements and analysis. The algorithm of vibrational prognostication of operating conditions of the frictionless bearings in the locomotive traction motors is suggested and grounded

A study of the influence of non-linear parameters spring of a freight car suspension (stiffness spring, length base of a bogie, roughnesses railway) on the amplitude and phase fluctuations bouncing body is completed. Defined own vibrational frequency jumps car body as a function of the parameters.

Based on the analysis of the empty rolling stock on the Krasnoyarsk and East Siberian Railways, the technical parameters that have a significant impact on the unloading of the wheel of the first wheel pair in the course of movement are determined. The design features of wagons influencing the safety coefficient of train traffic are considered. Statistical processing of these gatherings, according to the materials of official investigations, revealed a number of interesting features. One of them is non-normalized total gaps in the sliders along the diagonals of the wagons. This fact in the movement of empty car causes misalignment of the body, which in turn leads to a redistribution of the loads acting on the spring kits on the sides of carts and wagons. The influence of elastic suspension parameters (height, spring break) on the redistribution of loads acting on the sides of the trolley is considered. The misalignment of the body of empty wagons, especially wagons with a sufficiently small mass of unsprung parts and a high center of gravity, leads to a significant reduction in the safety factor. The calculation of the transverse guiding forces acting at the point of contact of the wheel and rail, as well as their effect on the unloading of the wheel. It is revealed that the body skew leads to a significant increase in lateral force, which affects the stability of the empty rolling stock.

The method of wheels and rails adhesion mode determination for locomotives based on Fisher statistical criteria is designed. Freight DC electric locomotive 2ES10 experimental trips on Sverdlovsk railway data processing results are presented.

Traffic safety of trains is a priority task of JSC «Russian Railways». In article the reasons of spontaneous operation of brakes of freight trains are investigated and their statistics depending on density of brake network of the train is given. Calculation of pressure in the camera under the equalization piston of the crane of the driver is made. Inertial characteristics of the equalization piston and its static characteristics are defined. Process of spontaneous operation of autobrakes on the basis of fundamental laws of a hydraulic gas dynamics is simulated.

In article it is made a calculation contact pressing taking into account change of aerodynamic carrying power depending on climatic conditions (in one and a two-phase stream), and as at change of working height of a current collector. Comparison of the received results with experimental data is executed.

The analysis of the causes of low efficiency of existing knowledge about the dynamics of the locomotive traction drive. It was found that the use of scientific information is difficult because of its inconsistency and lack of systematization. The classification of dynamic phenomena in the locomotive traction drive to facilitate the search for new technical solutions. Classification is used to create a new design rubber-cord coupling protected by a patent.

The influence of parameters of the spring suspension of freight wagon and axial load on its dynamic qualities and traffic safety. Showing the flaws of the standard three-piece bogie, influencing the dynamics and traffic safety. Investigated the horizontal dynamics of the of freight vechicle and the value of horizontal stiffness of spring suspension bogie for unoaden vechicle .

On the basis of a previously proposed General method of using a database of measurements onboard system parameters diesel generator set of shunting locomotives a technique of determining the distribution law of the values characterizing the intensity of change of current of the traction generator, evaluation parameters, determining a model function of the parameter changes on the overhaul period. The technique and criteria for assessing the technical condition of the diesel generator set of the observed locomotive using the model function are given

Now the problem of development of the high-speed and high-speed movement on the main railway transport that is connected by increase of traffic safety of trains and ensuring reliable work of contact suspension brackets and current collectors of an electrorolling stock is actual. For increase of reliable work of current collectors there are some ways one of which is creation of the safety devices which are built in a design of current collectors and providing their automatic lowering in emergencies. In Omsk State Transport University the current collector equipped with safety devices of new generation on the basis of the operated pneumatic devices and providing protection at failure or the increased wear of contact elements, and also breakages of a runner is developed; at rise on height of more admissible at departure of an electrorolling stock for the sign «End of a Contact Suspension Bracket» or break of contact wires; at blows and arrivals on obstacles in a contact suspension bracket. For control and management of operation of safety devices the protective pneumatic contour located on the basis of a current collector in the special case is used. At operation of one of safety devices there is a depressurization of the pneumohighway of a protective contour therefore pressure of compressed air the drive of a current collector decreases and it falls under the influence of own gravity. Restoration of a current collector possibly only in the conditions of depot or point of maintenance of locomotives. Calculation of characteristics and parameters of the device of protection at blows and arrivals on obstacles in a contact suspension bracket needs to be carried out by the given technique for zones of normal, dangerous and emergency work. For an assessment of operability of safety devices and definition of their main technical indicators and parameters in laboratory of OSTU the shock and oscillatory complex is developed for research of interaction of a current collector with a contact network.

In the article the possibilities of improving the adjustment properties and technical characteristics of electric rolling stock with collector traction motors are considered. Semiconductor devices can improve the smoothness of the traction motors start-up due to a more even voltage increase, smooth regulation of the field current in the traction and braking modes. Variants of simplified power circuits of eight-axis direct current electric locomotives with a minimum number of switching electrical devices have been developed, allowing to reduce weight and size of the equipment, increase the reliability of power circuits operations. Circuit solutions for protecting the wheelset of an electric locomotive from boxing and skidding by enhancing the traction motors field are considered. The role of semiconductor converters in the improvement of rolling stock with a combined and dual power is noted. The ways to improve the efficiency of electric braking by collector traction motors are listed. The necessity of using adaptive microprocessor control systems for semiconductor converters for expanding their functional capabilities and realizing optimal parameters of direct current rolling stock is noted.

The article presents the results of experimental studies to assess the possibility of using thermal methods of controlling the leakage of the boiler of a railroad tank car. This paper reflects the research of formation of the thermal field on the outer surface of the tank in the area of end-to-end defect such as a crack, by throttling through the gas medium due to the pressure differential. Presented thermograms show the localization of the defect with a detailed description of the anomalies of the thermal fields, recorded by the imager. Also confirmed the experiments described in the work on Joule and Thomson for throttling gas through local obstacle.

Possibilities of expansion of settle of typical elementary links of mechanical oscillation systems are considered. As examples of links for transformation of movement the screw and level mechanisms are offered. Introduction of new links is equivalent of elementary links with transfer function of differential of second order. The method for definition of parameters of dynamical absorbtions of oscillation are offered.