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In the article the most effective way to detect heat losses associated with loose-Stu walling. A method for use of aerodynamic and thermodynamic - cal research with the possibility of the use of rail transport.

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 subject of the study is the fuel utilization system of a diesel power plant as a diesel locomo-tive or other vehicle main lead, which is a complex technical system consisting of actual diesel in-ternal combustion engine, fuel lines and low pressure fuel processing and high pressure line includ-ing various elements of liquid fuels consumption dosing and control. The aim of our study was to analyze the system functioning, to determine the dynamic proper-ties and the nature of changes in the internal parameters of the system as a whole. To achieve the goal the system analysis methods were used. The processes of complex technical system operation were interpreted by means of the continuous linear stationary deterministic model of the list of others. For this particular model the body of mathematics developed on the basis of linear differential equations with constant coefficients is the most complete one. The chosen mathematical model was presented by us in the first stage in the form of a finite graph as a subgraph of obtained earlier generalized model which had both methodological and theoretical foundation. In accordance with the methodology of the systematic approach the graph model of the diesel power plant fuel utilization system operation was described in relation to major significant factors affecting the system parameters transformation dynamics. Given the complexity of the of fuel ignition and combustion mechanism located in the diesel engine cylinder, the use of the techniques of the modern automated control theory is adopted for numerical processes simulation with the system described in terms of the said theory. The criteria of efficiency, mechanical loads and thermal loads levels were chosen as the fuel utilization system internal state variables. Taking into account the Pareto principle the most important efficiency criterion components were chosen for the analysis; and the system of differential equations of the efficiency dynamics in the form of three balance equations was created. The factual description of the included equations allowed us to derive preliminary qualitative conclusions about the dynamic properties of the internal criteria: controllability, observability and stability of the fuel utilization system. The differential equations system parameters linearizing procedure and the introduction of small deviations allowed us to obtain the dynamic mathematical model of the fuel and air transfor-mation in the diesel engine heat cylinder. As the result of transformations we have obtained the equations presented in the form of the matrices, which allowed us to conclude that the process of the fuel and air transformation in the cylinder is controllable, the system is asymptotically stable, and the process is stochastic with the presence of perturbing parameters influenced by the engine's variable modes of operation. The further research areas have been suggested, and the practical results have been predicted: the creation of optimal (in terms of efficiency) control system with the technical solution in the form of the optimal controller (in relation to fuel consumption).

In this article outlined some results of dynamic tests of the gondola with biaxial bogies ZK1 type. Done the comparative calculations for the study the influence of carriages to the main dynamic performances.

The article discusses the control systems for mechanical vibrations on the basis of improved modernized nonlinear inverse dynamics algorithms and its use for vibratory stands of technical diagnostics to diagnose mechanical products of railway transport systems.

The necessity of searching for new methods to improve the dynamic rationalized properties of the traction drive, which does not create contradictions between the conclusions based on the results of numerical parametric analysis and the results of the analysis of nonparametric factors, is established. A modified base point method is proposed that takes into account the possible presence of areas of conservatism of a rational parameter and provides for a procedure for checking for conservatism. The search results using this method for a rational version of a traction drive with a support-frame suspension of an electric motor and a gear reducer coincide with the empirical choice of different manufacturers of locomotives.

At present, the “Afrosiyob” high-speed passenger train runs on the Tashkent - Samarkand, Samarkand - Karshi, Samarkand - Bukhara sections. In the near future, it is planned to launch freight trains on sections of the Bukhara-Misken route. On high-speed double - track sections Tashkent - Samarkand, Samarkand-Navаi, the movement of freight trains is combined with passenger trains. Which, in turn, negatively affects the throughput of stations and hauls. In connection with this, the actual issue is the movement of freight trains on these sections. Additional research is needed to increase the capacity of sections where freight and high-speed passenger trains run. The article considers options for the aerodynamic interaction of freight and high - speed passenger trains moving in one or the opposite direction. At the same time, the idea of the safe organization of freight trains during the movement of high-speed passenger trains was put forward. As a result of this study, the possibilities of carrying cargo trains in one direction or in the opposite direction are determined by ensuring the safety of movement on two-way parcels in which high-speed “Afrosiyob” high - speed electric trains travel. This makes it possible to develop recommendations for more effective use of the ability of parcels to conduct trains. When calculating the aerodynamic interaction, scientific ideas put forward by scientists from Europe, the USA, Russia and other countries were analyzed. Methods for solving the Navier - Stokes equations using existing programming models are described.

The actual process of interaction of pantograph with catenary associated with random processes. The main factors affecting the pantograph are vibrations of the rolling stock, aerodynamic, the instability of the dynamic properties of the pantograph and overhead catenary, etc. In view of the plurality of influencing the current collection of factors theoretically investigate the dynamical system "Pantograph - catenary" in full It is a complex task. A more rational to theoretical studies and sufficient for practical use is to consider deterministic processes. In the numerical simulation of the current collectors are the most common types of the following design schemes (models): lumped mass pantograph model; pantograph multibody schematics; pantograph multibody schematics in CAD-systems, which describe in detail the geometric dimensions and physical properties of each element of the pantograph. In the design of the pantographs is an integral part of the calculation of interaction of pantograph with contact suspension. Contact suspension counted in the calculations in the form of a concentrated mass interacting with the pantograph skid or a spatial system composed of resilient elements of finite length (catenary with distributed parameters). The second type of catenary model is used in the interaction with the first two types of models considered by the current collectors. Based on the features of each of the presented kinds of models, present the technique of the pantograph model selection, depending on the purpose of the simulation.

Purpose. Constructing a model for predicting a quantitative indicator of the pre-discharge state of the upper structure of the track based on a statistical analysis of the seasonal dynamics of this indicator. Forecasting involves identifying bottlenecks for timely corrective action. This approach allows you to refine the construction of algorithms of the functional risk assessment system on the infrastructure of Russian Railways for managing the technical condition of the railway track and safety and is considered as an element of digitalization of the risk assessment of traffic safety in the Railway Infrastructure Directorate. The development is carried out on the basis of accepted existing regulatory documents and classifiers of risk factors operating for the infrastructure management at Russian Railways. Methods. regression analysis, data validation, modeling based on regression analysis. Results. Dependence was identified and a forecast model of the dynamics of the number of deviations of the 2nd degree rail gauge geometry (GRK) was built based on the use of actual data from the automated system Path (APCS P) of Russian Railways. Testing of the approach was carried out on the basis of the Directorate of Infrastructure of the North Caucasus Railway. The identified dependence allows you to give a fairly accurate forecast of the state of traffic safety and the development of GRK deviations on the 2nd degree for use in practice, effective planning of material costs for planned preventive work and overhaul at linear enterprises, on a specific railway adopted for calculation and on the network of Russian Railways. Practical significance. The constructed model allows predicting the intensity of the risk factor on an objective basis of seasonal patterns, as well as the volume of control impacts on the current content of the upper track structure. The presence of such a forecast will make it possible to establish a relationship between the indicator of the dynamics of the number of deviations of the 2nd degree rail gauge geometry, including seasonal dynamics, and the risk factor, that is, the number of GRK deviations of the 3rd degree used in the risk assessment on the infrastructure. The result of this approach is the solution of a system of tasks that affect the values that reflect the level of risks, and as a result, effective management of financial flows for the maintenance of infrastructure, reduction and prevention of traffic safety incidents.

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.