Voloshchuk V. Modeling of thermal state and power receptivity of vehicle drum brakes and determination of their rational structural parameters

The object of research - generation, accumulation and dissipation of heat in friction pairs drum-shoe brakes cargo vehicle under braking at the time and method of their reasonable design parameters. The purpose is to study the regularities of temperature field, the number generated, accumulated heat and scattering in time at different sites in friction braking drum-shoe brakes of the vehicle in conjunction with the definition of reasonable design parameters. To achieve this goal is necessary to solve such problems: improved mathematical model of the friction pair-block brake drum; to evaluate qualitatively and quantitatively the components of thermal balance of the drum brake linings and friction laws; to improve method of calculation of structural parameters of the brake drum of the vehicle; to analyze the adequacy of the thermal model of friction pair-block brake drum on the results of experimental research; suggest improved design of friction knots drum-block brake of the vehicle. Research methods are the theory of heat conduction and heat transfer processes, the theoretical thermal dynamics method combined with iteration time to build thermal models, planning the experiment to determine the surface temperature of brake, mathematical statistics and regression analysis for data processing, geometric programming to determine reasonable design parameters. Scientific novelty: a systematic approach has been improved with the use of iteration in the study of fast thermal processes that occur on different modes of inhibition; Further development of methods to assess the thermal dynamics of heat flow in friction units of drum-shoe brakes of the vehicle; Determined new relationships between design, physical and regime parameters of friction knots of drum-shoe brakes on the basis of the research using the geometric programming; Further development of conceptual solutions for reduction and alignment of loading in friction units of drum-shoe brakes of the vehicle. The results of theoretical and experimental studies should be used in project organizations and design bureaus automobile factories in improving existing and designing new types of friction knots of drum-shoe brakes. The main results of drum-shoe brakes used in association "Avtobus" (Lviv).