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The article discusses the possibility of determining the specific fuel consumption of diesel locomotives in operation using indirect calculation methods based on the use of these locomotive onboard systems and supplementing them with mathematical models of the operating cycle and the model for determining the composition of the exhaust gases of a diesel engine. The basic equations and algorithms proposed for the implementation of such a method of mathematical models and the results of their use are presented, the results of a comparison of simulation results and experimental data on the specific consumption of fuel of diesel locomotives TEM18DM are presented. A possible algorithm for their joint use is proposed, conclusions are made on the possible development of such a method for determining the energy efficiency of diesel locomotives without taking them out of service.

The article describes the calculation of parameters of diesel fuel equipment on the nature of the change and the amount of fuel injection. Provides an implementation of the mathematical model of the fuel to be used when the kits before you install them on diesel and for calculation of parameters of parts used in the high pressure fuel pumps running on stands with a view to approximating the conditions of work in the booth to real conditions of a diesel engine and determine the correct performance of the pumps at the stand.

The experience gained in the operation of high-voltage vacuum circuit breakers VBO-25-20/ 630UHL1 indicates an incorrect assessment of the mechanical resource of its individual components and elements. Despite the repeated improvement of the design of the main switch drive, applicable both as part of the new «Ermak» series locomotives starting from number 1000 series, and in earlier numbers, the dynamics of malfunctions continues to persist to the present time. One of the most important elements of the main switch is a latch designed to hold the elements of the drive mechanism in the on position, the failure of the latch entails the failure of the entire section of the locomotive. The article considers three latch upgrades previously proposed by the manufacturer, a kinematic scheme of the drive with a vacuum arc-extinguishing chamber of the switch is developed, the parameters of the preload and trip springs in the drive are calculated, the forces operating during operation are determined. On the example of the latest modernization of the latch using the finite element method in the SolidWorks Simulation software package, a strength calculation was carried out, according to the results of which the stresses arising in its design were determined. As a result of the analysis of the finite element model, the forces critical for the structure are determined, a graph of the dependence of the structural strength margin and the maximum stress in the structure on the acting forces is developed. According to the results of the study, the force at which the most favorable value of the safety factor is provided is determined, for which it is proposed to reduce the critical force by changing the parameters of the compression springs and disconnecting the drive of the arc extinguishing chamber. A loading diagram with the drawing dimensions of two modified springs has been developed.

The article contains information about policy public corporation «RZD» in energy-saving and energy efficiency. Assessment of energy efficiency of application back-to-back method in testing induction tractive motors was executed as an example on modeling testing process of motors type NTA-1200.

In article presented the mathematical model of fuel heating of the high pressure pipeline of diesel engines fuel equipment and calculation results of temperature of its external surface at various temperatures air and the fuel equipment technical conditions.

A theoretical and practical study of gondola cars equipped with various models of trucks: 18-100 and 18-9810. Compiled design scheme, system of differential equations and bringing its solution for different types of trucks. The analysis of the solutions of this system are found depending on the amplitude of the pitching and bouncing speed carriage movement. Found dynamic forces on the one spring group. Based on the comparison of the two bogies conclusions about the benefits of truck 18-9810.

The paper is mathematical description, which allows to evaluate the properties of the system at the stage of theoretical development. A model of the anti-vibration suspension system with linear adjustment, which allows to study the dynamic characteristics of vibration isolation system threads compensation rigidity. The results of simulation program Matlab.

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 ).

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 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.

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.

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.

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 .

In article there are fluid flow mathematical models at the UV-sterilizer with concentric pipes installed in modernized water supply system of passenger car allowing to determine the velocity field of the rotational velocity component and assess the degree of attenuation depending on the chamber disinfection geometry, the inlet pressure in the water system, and fluid properties. There are exact solutions of the Navier-Stokes equations for a rotating fluid between fixed cylinder of infinite length and limited fictitious determined rotating lids provided Poiseuille axisymmetric flow. The decision explicitly contains the product of cylindrical Bessel functions and hyperbolic functions.

The subject of the study were made of the injection and combustion in diesel locomotives and ships, which are the most difficult to analyze, operate and forecasting facility management (processes in the cylinder of a diesel engine), where the conversion of thermal energy released during the combustion of fuel into mechanical work takes place through a series of successive physico-chemical, thermal, mass transfer and thermodynamic transformations which together constitute the circular irreversible and unlocked the duty cycle. However, the direct study of the operating cycle is still difficult complexity of the totality of the factors influencing the course of the process as a whole. The aim of the work was to establish an empirical connection laws fuel supply and combustion process in diesel cylinder it, ie the creation of methods of calculating these processes together. One approach to establishing formal relations and the possibility of subsequent numerical modeling of combustion processes and communication of the law the fuel in a diesel engine is the use of the theory of automatic control, which developed methods of identification, taking into account the processes of management system in the form of a model of a cybernetic system. It is concluded that the numerous experimental and computational studies suggest that the dynamics of the fuel significantly affects the combustion process in a diesel engine, and, consequently, its power and economic performance. Then to establish a formal link (model) combustion processes and the law the fuel used machine control theory (TAU), which uses and develops methods for the identification, considering processes management system in the form of a cybernetic circuit. Assumed that the full range of processes in the combustion chamber since the start of the fuel supply to the end of its combustion is a complex dynamic system of self-governing. The formulation was based on statistical methods for solving the problem of identification, where the input variable and its response (the law of supply and indicator diagram - experimental curves) are stationary random functions, and object management (combustion) is classified as a one-dimensional linear lumped. As a criterion of proximity to the object used criterion of the minimum of the expectation of a given function of the difference of the input signals and the object model. It is noted that there is currently no accurate method for calculating the finished analytically binding processes fuel supply, mixture formation and combustion in a diesel engine. Therefore, there is not yet calculated optimum injection characteristics suitable for the calculation and simulation processes in diesel engines of various types. It was found that, other things being equal, the law determined by the rate of injection of fuel injected. Striving to achieve injection with increasing speed in order to reduce the cycle dynamics, as well as more efficient use of the air charge in a distant "corners" of the combustion chamber (the latter portion of fuel, with a maximum speed to penetrate into the remotest corners). It is shown that in most cases it is necessary for the administration of the mathematical description of establishing the relationship between input and output variables, based on which can be worked out such a control object, which would ensure achievement of the intended target operation of the facility. With regard to the solution of a specific problem the most common case is when and exposure and response will be functions of the same argument. Thus, determining the experimental data of the conditional expectation of the output variable with respect to the input, we obtain the optimal (in the sense of the criterion of minimum mean square deviation) Estimates of the object. Given the accepted method of identification and characteristics of the problem, the best operator in the class of linear operators, and not among all possible random variables. This study was based on the principle of superposition, which is performed for a linear operator. Using the hypothesis that the investigated signals have the property of ergodicity with respect to the correlation functions. The adoption of the hypothesis of ergodicity possible to determine the correlation functions centered on the realization of a random process, ie, combustion process, as successive cycles. Noted that most fully identifiable objects are described in terms of the state space. Under the state of the object understood set of values, fully define its position at any given time. Proposed a model of the considered dynamic objects to choose a system of differential equations. In view of the above, the proposed approximation algorithm to determine the dynamic characteristics of the combustion process, ie, the agent object in the class of linear operators, which was presented as a system of differential equations representing the desired mathematical model.

The results of mathematical modeling of the heating process of the wheel material during braking mode of the locomotive are presented in article. The results can be used to calculate the temperature change for any point of the wheel during the braking operation.

In this article the problems of efficiency of functioning of production systems of the locomotive repair enterprise are solved. In particular, the object of research is the technological processes of repair and maintenance of electric locomotives at the enterprises for repair of traction rolling stock. The article presents a mathematical description of the production process of such enterprises, on the example of the service locomotive depot «Moskovka». The mathematical model is described on the basis of queueing theory (QS) and Markov chains. A graph of the technological state of the locomotive during repair in the depot, where the process of transition of the repaired rolling stock from the state to the state, i.e. the relationship of technological movements of the electric locomotive on the territory of the depot, as well as the time of technological operations described transition matrix. The distribution of repair requests is described by the Poisson law, the delay of the electric locomotive in the depot areas in the planned types of repair in accordance with the accepted norm, and in the unplanned form of repair, the applications are delayed in accordance with the distribution of erlang. Based on the results of the mathematical description of the model of the production process of the repair enterprise, a simulation model of the operation of the Moskovka depot was created, implemented on a computer with the help of professional software of a new generation - AnyLogic. The paper describes the logic diagram of the simulation model, selected methods and modeling libraries. According to the results of the study, the overall assessment of technological performance indicators of the locomotive repair enterprise, in the conditions of probabilistic, dynamic changes in the repair task. By means of the methods of research of technological processes of depot «Moskovka» realized in article, it is possible to design any repair enterprises on repair of a rolling stock of the railroads, for the purpose of identification of «bottlenecks» of production process.

One of the properties of the reliability of the power supply of electric rolling stock of railways is the trouble-free operation of the traction power supply system in various modes of its operation. For post-emergency and forced modes of operation of the traction power supply system, a decrease in load capacity is characteristic. In order to ensure the throughput and carrying capacity of the railway section by traction power supply devices, it is proposed to consider the use of electric power storage devices on electric rolling stock and in the traction power supply system. Studies conducted by domestic and foreign researchers allow us to evaluate the effectiveness of alternative solutions to improve the reliability of power supply, which include various options for the use of electric power storage devices on electric rolling stock and in the traction power supply system. This article presents the results of a review of these solutions, a simulation model of a traction power supply system and an electric rolling stock with power storage devices based on various batteries and a supercapacitor is proposed. Modeling of changes in the modes of operation of the traction power supply system is carried out taking into account the state control of switching devices. The calculation results allow us to estimate the voltage drop at the output of electric power storage devices, including taking into account the exponential zone of the discharge characteristics of batteries, to estimate the voltage change for a given electric traction load depending on the energy intensity of the storage device, made on the basis of the most common types of batteries and a supercapacitor.

Formed research methodology of assessing the impact of pulsed exposure with the one-hundred-Rhone joints of rails on the performance of the dynamic characteristics of the train crew. The dependence of the coefficient of the effect of pulse repetition on the level of energy dissipation in the system and the speed of the crew.

Considered forced oscillations of four-axle vehicle with dual spring suspension. It is obtained that the movement system with six degrees of freedom with sufficient accuracy can be represented by a system with two degrees of freedom. Therefore, the vehicle body has two degrees of freedom: lateral skidding and wobbling, Bouncing and galloping trucks will be neglected. The total number of degrees of freedom of the model equal to two. The method, which leads to a closed solution of the forced oscillation. Defined. That tends and to (n = 1, 2,…), the amplitude of the oscillations will be unlimited. Therefore, the parameters k1, k2 and T must be selected on the basis of required values of amplitudes. As a result of research compiled by the differential equation of motion of the system and obtained analytical solution for the case of external piecewise constant driving force.

The article considers a suitability of mathematical model of stretched rod to determine the relationship of the parameters oscillations of the contact wires and their tension. This model allows you to determine the tension by the frequency oscillations of the contact wire obtained after the passage of the current collector. In this case, the speed of the electric rolling stock will not affect the frequency of the damped oscillations. Thanks to the proposed model, the labor intensity is reduced of determining the tension of wires without interruptions in the movement of trains is reduced and there is an opportunity of operational monitoring of the state of the contact suspension remotely.

This article contains results of experimental studies on the formation of corrosion products as a result of aggressive environment and electric currents action on the reinforced concrete structures. There are discussed a method of creating models with artificial electrocorrosion under conditions close to real working. The results of testing models using the X-ray method and modeling their strength characteristics are presented.

In article the way increases in system effectiveness of cooling locomotives in operation - use relaunches of heat carriers between contours is considered.

The article discusses the approach to generalized evaluation of technical condition of the diesel locomotive power plant functional subsystems based on the reduction of private parameters extracted by results of the analysis graph model to one-dimensional time function with use of mathematical expression of a nonlinear medium. Results of generalized evaluation of technical condition of the power plant fuel system are presents.

A kinematical system of the test bench for experimental investigations of the frequency asynchronous driving gear is consider. Description of the kinematical system and mathematical model on the assumption of back-to-back is produces. As well as example of construction of the mechanical data family on basis of experimental data taking into account of the inner loss in the system is produces. Dynamical model of the asynchronous motor and results of the modeling in matlab simulink is produces.