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This article describes different ways of mass-burned fraction curve calculation, shows the Pugachev’s combustion rate equation structure, method of this equation factors selection and simulating versus experimental data matching.

Article is devoted to mathematical modeling of heat transfer to the cooling system of locomotive diesel engine . The article presents the features of calculation of heat to the cooling system of a diesel engine when idling.

The article presents the method of calculation of heat capacity working relations in the process of fuel combustion. Analytical dependence of heat capacity ratio are presented depending on the temperature of products of combustion, excess air ratio and proportion of burnt fuel for different formulations of mixed types of hydrocarbon fuel.

On the basis of experimental data thereis a mathematical model in thisarticle. Its made from the registration options in acfual operation mode of the locomotive. This mathematical model describes the technical condition of the locomotive and evaluates the parameters and characteristics. Considerable attention is paid to complex state operation of the facility. In dealing with the mathhematical model it’s defined the main locomotive operation indicator.

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.

The article deals with the cooling and heating of individual components and assemblies diesel engines at low ambient temperatures. The more attention is paid to the description of the characteristics of the intensity of the cooling water system of diesel locomotive engines. The article presents the results of investigation of the outdoor temperature , operating conditions of load and no-load on the cooling system of. The parameters of the cooling water and engine oil that characterize the thermal conditions of the diesel engine. We reviewed and analyzed various ways of warming systems, diesel engines using airborne and stationary devices. The work is aimed at improving the efficiency of diesel locomotive at warming by reducing the operating time of the diesel engine is idling.

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 physicochemical properties of diesel fuel and methyl ester of rapeseed oil are reviewed, graphical dependencies of density, kinematic and dynamic viscosity, surface tension of diesel fuel and rapeseed oil methyl ester are shown when the temperature in the diesel cylinder changes, chemical indicators of methyl esters of rapeseed oil on the characteristics of injection and spraying of fuel.

In this article, the main methods of technical diagnostics of diesel fuel equipment are considered. The faults they detect are listed. The principles of the methods work are examined in detail, the shortcomings and advantages of the chosen methods are revealed.

The technical condition of the cylinder-piston group has significant effect on the reliable operation of the diesel locomotive engines. The most susceptible to the premature failure is the head of cylinders. It is caused by the heat release rate of the combustion chamber detail. The increase of the diesel locomotive engines cylinder heads durability in operation causes the relevance of the researches. In the article the set of the factors influencing on the diesel locomotive engine cylinder heads durability is defined, their main groups and subgroups are found. In the offered classification the subjective factors which directly depend on the human activity are dominated. It is possible to reduce the influence of the subjective factors by means of the human activity wrong solutions reduction while operating and repairing locomotives. The measures that improve diesel locomotive engine operation and positively affect the reliability of the cylinder heads are considered. Simple in implementation methods to extend the service life of the cylinder-piston group are offered. They are decreasing temperatures gradient during the post-stopping period of the power point and upgrading cooling system.

Process operating diesel locomotive associated with the gradual deterioration of parts of the cylinder-piston and crank mechanism. Periodic assessment without taking for the pieces of these groups is possible when using a method based on an analysis of the current values of the control concentration of wear. One of the main problems in the implementation of this method is the problem of estimating the amount of metal worn with controlled parts on the analysis of the current values of the concentration of wear. The article describes the method of calculation and simulation results of the system clean engine oil diesel D49.

The reliability of diesel engines is mainly determined by the reliability of operation parts of the cylinder-piston group and crank mechanism. High-quality cleaning of engine oil during operation of mechanical impurities, provided filters coarse, fine filter and centrifugal filter, reduces the rate of wear and tear. The results of simulation of a centrifugal filter to assess its efficiency and the quality of screenings of particles of different sizes in the process of exploitation.

The article is devoted to one of the urgent problems in the activities of JSC “RZD“- increasing the energy efficiency indicators of locomotives, namely, new generation locomotives running on liquefied natural gas (LNG) - GT1h series gas turbine locomotives. The results are presented for the analysis of typical diagrams of traction work at hauling trains by the gas turbine locomotive on the Surgut - Voinovka section of the Sverdlovsk Railway. Measures are proposed to reduce the specific consumption of the fuel used for hauling operations for various running duties of a gas turbine locomotive (traction mode, idling, transient modes). The justification and description are given for the selected technical solutions to reduce fuel consumption by the “gas turbine engine-traction generator” system during gas turbine locomotive operation in idle and traction modes. The results of tests of the gas turbine locomotive during idling and in traction mode using the proposed technical solutions are presented. The comparative analysis of the results obtained is carried out and the economic assessment of the effectiveness of the selected measures is given when the gas turbine locomotive is operating in idle and traction modes. A mathematical model is proposed for the electric traction drive and the automatic control system of the gas turbine locomotive, developed using the Matlab Simulink environment and designed to study the operation and optimization of electromagnetic processes occurring in the electric traction drive of the gas turbine locomotive in various modes of its operation. Based on the results of modeling the algorithms for the operation of the automatic control system (CAP) allowing to provide energy-optimal loading paths for the “gas turbine engine - traction generator” system in the entire power control range, the economic assessment of the effectiveness of the CAP algorithms is given. The economic assessment is presented for the implementation of a set of proposed measures to improve the energy efficiency of gas turbine locomotives.

In article stages realization of complex systems non-contact thermal control of the main knots and systems locomotives are considered. The developed techniques of an assessment technical conditions sections refrigerators, electrical machines and the fuel equipment of a high pressure locomotives with use thermovision control method are presented.

The results of the study the possibility of using artificial neural networks in identification problems failure status diesel D49, the results of spectral analysis of the crankcase oil. The obtained results are needed to develop software for evaluation of the degree of wear and tear as a result of the diesel locomotive spectral analysis of engine oil.

Theoretical analyze of liquid fuel movement in low-pressure line (LPL) of diesel fuel supply systems is implemented. To solve LPL the equations set of homogeneous blend is suggested. It is shown that when using alternative fuels in locomotive and ship diesels the retrimming of fuel equipment is required, and it’s reasonable to use the degree of irregularity of working process as diagnostic indicator.

In article stages developments of power plants autonomous locomotives from the steam-engine to gas-turbine engines and engines on fuel elements are considered

There are results of researching regularities of chafing cylinder-piston group and crank rod mechanism in the diesel engine D49. The results are necessary for creation method of diagnosing locomotive diesel without taking for the pieces but just with the results of spectral analysis of engine oil.

Cleaning of engine oil from contaminating particles and products of wear of parts is an integral part of reliable operation of friction parts of locomotive diesels. The presence of solid particles in the oil leads to abrasive wear of the parts, and as a result reduces their resourceability. Onboard cleaning systems used on locomotives are not able to carry out fine-dispersed cleaning of engine oil. It is proposed to use an external stationary installation of centrifugal cleaners, which will increase the efficiency of cleaning and clarification of engine oil in the planned types of repair and maintenance of locomotives.

The analyze of fuel supplying methods in diesels with respect of fuel properties was implemented. The new method was suggested, which can estimate impact of physical and energy fuel properties on power and economic indexes of a diesel. The diesel effective work conditions on low-viscosity fuels are formulated, including regulation and constructive changes in fuel supply system.

In the practice of railway transport and the locomotive complex, the average statistical data used in practice are not homogeneous, which is usually called “average temperature in the hospital” in the literature. The homogeneity of data is determined by their unimodality, i.e. the presence of one process in the sample. Unsuccessful sampling leads to its bimodality and even multimodality. It is proposed to check for unimodality of the initial data using the consequence of the law of large numbers, according to which, with an increase in the number of data, homogeneous samples tend to one of the distribution laws of a random variable: normal, exponential, lognormal, or another known law. Therefore, any unimodal sample must meet the goodness-of-fit test, which the article proposes to use the Pearson test (“chi-square”, χ2). The unimodality of the data is proposed to be estimated through the probability of compliance with the law of distribution of a random variable chosen for consideration, considering the probability of more than 0.3 (30%) to be sufficient. On the example of locomotive operation data and on-board microprocessor systems data, data are shown that cannot really be unimodal, but there is data that requires changing the sampling rules to achieve unimodality. For example, when considering the average daily runs of locomotives by series at specific home depots with participation in one type of traffic (main traffic, shunting or switching work), unimodality is achieved. An attempt to enlarge the data (take several series, several polygons, etc.) leads to the loss of unimodality. The article considers the unimodality of these on-board microprocessor control systems MSU-TP for diesel locomotives of the 2TE116U series. The expected operating time for the positions of the driver's controller turned out to be multimodal data. Unexpectedly, the current of the traction motors turned out to be unimodal, regardless of the driving position of the driver's controller.

In article from positions of uniform life cycle locomotives, from creation before write-off, the major factors influencing the level of their reliability are considered. Value of these factors will give the chance to connect mathematical model the potential level of reliability put in the specification on design of new locomotives with the actual reliability in specific conditions of operation and on this basis to determine the optimum parameters systems of maintenance and repair corresponding to maximum efficiency of use locomotives for all life cycle.

The paper considers the use of simulation modeling in the reengineering of technological processes for repairing rolling stock units on the example of repairing a bogie model 18-578 of an open-top car. The most time-consuming sub-process of repairing the bolster of this bogie was considered as the object of reengineering. Three options for reengineering of this subprocess were considered, implying a complete replacement of the technological equipment currently in use at repair operations (positions) with more efficient positions of the subprocess. To substantiate the choice of the most preferable reengineering option, the values of such indicators of the functioning of the subprocess under consideration as its productivity per shift (throughput), the load factor of the resources used at the repair positions, the volume of work in progress at the end of the shift, the number of workers employed in production and the costs associated with the possible purchase of new technological equipment. Simulation modeling of the functioning of the considered sub-process of bogie bolster repair was carried out on the basis of the methods of the queuing theory. The construction of simulation models and their assessment of the above indicators were carried out in the Arena RockWell Software environment. When developing simulation models for each of the possible options for reengineering a subprocess, the discipline of its organization and maintenance was taken into account. In the article, for each of the reengineering options, the calculated quantitative estimates of the listed indicators are presented, obtained using the corresponding developed simulation models. The use of these assessments reduces the risks in the development and subsequent implementation of organizational and technical solutions associated with the modernization of the considered technological sub-process of repair of the bolster of a gondola car bogie.