Ivanov P. Yu., Dul’skii E. Yu., Khamnaeva A. A., Korsun A. A. Teoreticheskie issledovaniya osobennostei modelirovaniya protsessa friktsionnogo tormozheniya poezdov [Theoretical studies of features of train friction braking process modeling]. *Sovremennye tekhnologii. Sistemnyi analiz. Modelirovanie* [*Modern Technologies. System Analysis. Modeling*], 2020, No. 4 (68), pp. 150–158. – DOI: 10.26731/1813-9108.2020.4(68).150-158

10.26731/1813-9108.2020.4(68).150-158

This article studies statistical data that determine the relevance of increasing the braking efficiency of trains. It is concerned with the features of modeling the process of frictional braking of railway rolling stock. The authors conduct a brief review of international publications on the study of friction brakes of various types of transport. They consider the technique of determining the coefficient of friction of the brake shoe on the wheel for the railway rolling stock. The features of the method of determining the friction coefficient, which affect the accuracy of modeling frictional braking, are analyzed. A number of conclusions were made based on the analysis. It is assumed that the friction coefficient and braking force may change in a worn-out shoe due to an increase in the temperature in the contact zone with the wheel, because the shoe loses about 80 % of the original mass and 25 % of the heat exchange area with the environment. This significantly changes the energy balance and temperature in the friction zone. Thus, we can explain why trains with the same braking effort and other equal braking conditions in operation have different stopping distances. As a result of the study, it is concluded that the temperature of the shoes is taken into account in the formulas of the friction coefficient, but only for cases of braking in which the speed of movement is constantly decreasing, and the train tends to stop. It is not possible to use this coefficient with confidence to simulate long-term braking at a constant speed, since the temperature of the shoes will start to increase and, despite the constant value of the effort and speed, the coefficient of friction will begin to change significantly. The work indicates areas of prospective studies in the direction of development of the railway transport brake technology mentioned in the article.

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