| Breaking is a key issue for high-speed or heavy load in railway. Unless braking is solved, the safety of high-speed or heavy load will not be guaranteed even with high quality lines and super traction power. At present, disc and ingot shoe tread braking are mainly adopted in passenger cars. With the speed improvement of locomotive and high transition pace of internal combustion locomotive to electrical locomotive braking problems have becoming increasingly prominent.The chatter phenomenon always occurs in the condition of braking at low speed. It is a sort of high-frequency vibration belonging to low-sound-level friction noise which is very harmful .This vibration will strongly destroy the inside equipments of the car, parts of the bogie and brake system. It will deteriorate the stability of the vehicle, jeopardize the health of passengers. And the scream produced by chatter will aggravate the noise pollution of the railway line.The chatter is classified to the regenerate chatter, friction chatter and mode coupling chatter according to the chatter theory and vibration intensity the chatter of vehicle belongs to the later two forms. It shows that the negative slope curve of the friction coefficient and speed affects slightly to the chatter. So it is not the main reason. Primary study demonstrates that the locomotive chatter has close relationship with non-linear brake force and dynamical character of locomotive structure as well as their interaction. Due to incomplete mathematical model of chatter in large machines, dynamic behaviors caused by nonlinear factor in system have not been understood absolutely. It can not satisfy modern industrial design, so establishing dynamic friction chatter theory is urgent to disclosure nonlinear factor in system. This is very significant to improve the stability, safety and reliability of system. This research is based on the Theory of Oscillation Mode Coupling with Simulation soft.Firstly, this paper establishes a mathematics model of the chatter theoretically based on the Theory of Oscillation Mode Coupling. Secondly, the paper concludes the system parameters as chattering, important factors affecting chatter, with MATLAB/SIMULINK. 1 Overviewed research present state and perspective.2 Set forth mechanism of friction chatter, and found the negative slope in friction force-speed not to be the main cause of braking chatter generation.3 Analyzed and put forward reasonable disc and ingot shoe tread braking coupling mode.4 Obtained factors which are affect the dynamics of the brake system with simulation.5 Compared academic and simulation result, provided means to avoid chatter. |
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