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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 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.

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 ).

With the increase in the capacity of modern electric rolling stock providing freight and passenger transportation, the problem of transmitting large traction currents remains relevant, caused by the low load capacity of the pantograph, which can lead to overheating and annealing of the contact inserts with a subsequent decrease in their strength, peeling of graphite from the copper shell, and increased wear. The article considers the classification of various methods for increasing the load capacity of pantographs, the most promising of which is cooling their runners. The disadvantages of the known active and passive runner cooling systems include the need to use additional mechanisms and units to remove heat from the heated parts, which work effectively only when the electric rolling stock is moving or at a standstill. To eliminate this drawback, the authors proposed a technical solution for a pantograph runner equipped with heat pipes and capable of successfully operating in various operating modes of electric rolling stock. To test the operability of the proposed technical solution, its mathematical model was created in the SolidWorks software environment, which, using the FlowSimulation application, allows modeling the thermal processes occurring in the pantograph runner. When using heat pipes in the runner design, the heating temperature is distributed more evenly along its length, thereby improving the conditions for heat dissipation into the environment, which will allow higher load currents to pass through. The results of mathematical modeling of thermal processes in the pantograph runner in the SolidWorks software environment are confirmed by experimental studies on a specialized installation. The use of the proposed device facilitates a more uniform distribution of heat over the surface of the runner, reducing the heating of the contact inserts and increasing the load capacity of the pantograph and the reliability of its operation under conditions of high-speed, high-speed and heavy-haul train movement.

Currently, in the brake system of operated cars, there is a problem of lack of brake pressure on the wheel, which is necessary for the movement of the train at a set speed in accordance with the regulatory documentation. This is due to the tendency to increase the mass of trains and the maximum load of cars with a constant tare weight, which requires an extended range of pressure control in the brake cylinder by an air distributor or auto mode, depending on the load of the car. To solve this problem, calculations were made of the braking coefficient of cars equipped with air distributors № 483, which showed that the freight car was not equipped with brakes to run as part of a train at a set speed. In the course of engineering studies, it turned out that increasing the spring rate of loaded and medium modes can increase the adjusting range of the air distributor and partially solve the problem of lack of brake pressure. Thus, it is proposed to recalculate the stiffness of the adjusting spring. Calculations of the rigidity of regular and proposed springs were made. The braking coefficient has been recalculated, taking into account the increased spring constant. As a result, this coefficient has increased, which makes it possible to remove speed limits. The proposed method for upgrading the air distributor can be carried out on all types of repairs, which facilitates the implementation process.

The analysis of the influence of the organization of the formation of United freight trains on the throughput capacity of railway sections has been carried out. The results of electrical calculations of the 3.0 kV dc power supply system of 3 sections of the Sverdlovsk and South Ural railways are presented when controlling the speed of trains from 50 km / h to 100 km / h with various locomotives while passing two single and one connected cargo trains using the system of contactless automatic voltage regulation in the contact network, allowing to assess the throughput capacity of the three sections. In the course of the calculations, the developed refinement method was applied using the correction current factors KIxx and KIst. Proved the need for their use in electrical calculations.

In article process of expeditious calculation of capacity and intertrain intervals is considered within the concept of coordinate management of train service. The technique directed to the solution of problems of search of reliable intertrain intervals in real time, calculation of the postemergency set operation and estimation of reliability of traction power supply system, based on use of the device of artificial neural networks and modern means of interval regulation of the movement of railway transport is offered.

Some aspects of soil testing are discussed this article to determine the stamp bearing capacity of piles. The techniques of plating tests has been proposed with anchoring of the shell or casing piles future. This method allows you to evaluate the resistance of piles on its end and side surfaces.

Recently, during overhaul of the railway track using modern materials such as geotextiles and penoplex. In turn, they make significant changes to the structure of the ballast, t. To. Are almost insulators. OSTU experimentally it has been ascertained that the contact resistance in the case of using a new type of cloth can be raised to 45 - 150 Om*km. Obviously, this leads to a significant increase in the capacity of the rail relative to a distant ground and can cause injury to personnel operating the traction members network. To determine the capacity of the rail at any point area must take into account the redistribution of power in the elements of the rail network, ie. E. In the rail and the transition resistance «rail - the land». The rail network is characterized by longitudinal rails Zp kilometricheskim resistance, transition resistance «rail - land» rp-s, and the characteristic impedance ZB kilometricheskim spreading factor γ rail network. Analysis of the results lead to the following conclusions: 1) contact resistance «rail-to-earth» has a significant impact on the value of the potentials arising on the elements of reverse current flow circuit; 2) the growth of the resistance «rail-to-earth», associated with seasonal fluctuations in soil resistivity, as well as in recent times, with the capital reconstruction of the roadbed, resulting in a significantly longer (up to several tens of kilometers) area, for which the potential can reach hazardous the value of human life; 3) in the circuit mode on a rail (m. E. When a metal short circuit) almost always rail network will occur potentials exceeding admissible values for several kilometers in both directions from the point of fault, which leads to removal of the dangerous potential at all metal construction connected with the rail and therefore requires a review of the principles of grounding structures.

The article considers methods for optimizing traffic flow management in large agglomerations by using clustering, routing and principles of queuing theory. The main study is devoted to the redistribution of resources by introducing a priority system in request processing. The influence of urgency, density and throughput of cargo flow on the system operation is analyzed and optimization algorithms are proposed to reduce waiting time, reduce costs and improve the efficiency of transport processes. The research methodology includes the use of a multi-channel queuing model to assess the impact of priority distribution of requests on the system throughput. Mathematical modeling, linear programming methods and NPV calculation for assessing economic efficiency are used to analyze the redistribution of resources. The results of the study show that the priority service system reduces the waiting time for urgent requests, but under high load it can increase the waiting time for less priority clients. The developed resource redistribution algorithm adapts the system to changes in flow intensity. The use of the proposed methods made it possible to reduce the average waiting time for priority requests by 1.5-2 times and reduce operating costs. The practical significance of the study lies in increasing the efficiency of transport processes due to the dynamic redistribution of resources. The implementation of the proposed methods can be used in logistics, courier services and transport companies to optimize the processing of requests, improve customer service and reduce costs.

In article the problem of determination of length of turn of structures, the total loading capacity of the transport which isn't provided with freight, quantity of freight of the transport knot which is in a timepoint in a warehouse on the basis of definition of distribution of a random variable of the freight expecting loading or unloading, and also the free capacity of vehicles taking into account restrictions on the capacity of warehouses is considered. During the solution of a task the following assumptions are accepted: capacity of cargo handling devices of transport knot isn't limited; time of the translation of giving of cars for the pogruzoch-but-unloading front and back isn't considered. The structure is understood as conditional structure which loading capacity is equal to the total loading capacity of some party of real structures, and the moment of its arrival - to the arrival moment on transport knot of the last of them. The received results can be used for determination of optimum values of warehouse capacities and a technological stock of freight of transport knot at the set goods turnover.

Paper is devoted to the development of an improved algorithm for calculating the traction power supply system for further practical implementation in order to improve the accuracy of calculations of the traction power supply system by combining traction and electrical calculations with considering the current train situation. The relevance of the task is due to the need to improve the accuracy of calculations of throughput and carrying capacity under the conditions of power supply devices with considering the criteria for energy efficiency of the transportation process. The available solutions to this problem in the form of ready-made software systems and algorithms are considered. A numerical experiment was carried out for the DC section in the program "Complex of calculations for traction power supply", which showed that the relative error that determines the convergence of traction and electrical calculations is from 1.6 % to 5.1 %. The main reason for the discrepancy is the insufficiently correct calculation of the voltage at the current collector of the electric rolling stock. An improved algorithm for calculating the traction power supply system is proposed. The distinguishing feature of this algorithm is the implementation of a clarifying full traction calculation before compiling instant schemes and instant electric and traction calculations. As a result of the research, a general algorithm for joint traction and electrical calculations with considering the parameters of railway sections and the current training situation has been developed,. A conclusion about the advantages of the proposed algorithm and promising directions for further research is made.

Modern requirements for the organization of the transportation process depend on technological and infrastructural aspects. Traditional approaches to regulating car flows, including using methods to minimize empty runs of rolling stock, lead to the loss of profitable options for JSC Russian Railways to interact with customers in terms of organizing exports and imports with subsequent sale of these goods (products) in Russia. The technology of transporting coal in «Open Top» containers with back loading with imported cargo has advantages arising from foreign and domestic experience in implementing such transportation. This article focuses on the economic aspects of the technology under consideration, including reflecting the specifics and prospects for the development of container transportation of coal. A comparative analysis of economic indicators for several options for transporting coal is performed. For customers of railway transport and JSC Russian Railways, the feasibility of organizing freight transportation in «Open Top» containers with the formation of closed routes with back loading with imported cargo to an intermediate station is substantiated. It is noted that the savings of the closed ring route of coal and anhydrous calcium chloride in containers reach from 30% to 65% compared to the use of universal gondola cars. Given the current conditions of congestion of the railway infrastructure, the use of «Open Top» containers for the transportation of various goods is a key advantage of ring routes. This is important to consider when developing export-import relations with friendly countries.

The article presents the results of the studied soils on physical and thermophysical characteristics in the territory of the city of Omsk. The lack of such data can lead to erroneous calculations in the design of ground probes using low-potential energy of the earth. A method for determining the minimum distance between wells is proposed, which allows to eliminate soil freezing and increase the efficiency of heat transformers.

Within the framework of the article, a study was made of the workplace of wheelchair washers for the purpose of determining the main occupational diseases and the causes of their occurrence. The theory of constructing rational modes of work and rest for working in the off-season in the open air is considered. The equation of integral index of cooling conditions is given. The risks associated with working in the cold are listed, as well as basic protection measures for workers, such as personal protective equipment and recommendations for restroom equipment. Within the framework of the article, the technological stages of manual washing of passenger carriages and a number of harmful production factors at the workplace of wheelchair washers are considered. In the process of analyzing the working conditions of the profession in question, a number of prof. diseases such as acute intoxication, dermatitis and dermatosis. The results of the conducted tests for the evaluation of the toxicity index and operational tests of samples of the detergent «Trans-Eco» with the aim of improving the working conditions of the passenger car wipers are presented.