Study On The Form Reason Of Wheel Polygonization Based On Track Vibration

With the continuous development of China’s high-speed trains, wheel polygonization phenomena appears in some high-speed trains which resulting in abnormal vibration of the trains and affecting the normal operation of the trains, eventually causing huge economic losses. Now the form reason of wheel polygonization has not yet formed a unified conclusion. Therefore based on the track vibration, this paper analyzes the development of the mechanism of wheels polygonization; and establishes a rigid-flexible coupling high-speed vehicle system dynamics model. This model considers the wheelsets, frame and carbody flexibility in order to make the simulation more accurate. In this paper, the main work and the conclusions are as follows:1.According to the actual size of the high-speed train, a three-dimensional model is established, and the modal analysis is carried out to reduce the degree of the freedom; then using the commercial code SIMPACK developed the rigid-flexible dynamics model;2.The differences between the rigid dynamics model and the rigid-flexible model is studied, to provide a certain reference value for the engineering application of the rigid-flexible coupling dynamic model; and then the rationality and necessity of considering the flexibility of the structure is pointed out;3.According to the vertical vibration response of the track, the formation mechanism of the wheel polygonization is analysed; according to the principle of regenerative chatter of machine tool, the evolution mechanism of wheel polygonization is analyzed. By using the field measured wheel polygonization to simulate the influence of the wheel polygonization on the behavior of wheel/rail;4.Using the rigid-flexible dynamics model to simulate the influence of wheel polygonization order and amplitude on the system dynamics of vehicle; the results shows that the carbody ride index doesn’t apply to wheel ploygonization. Different order of the wheel polygonization will occur resonance with the wheeset’s first bending mode in corresponding velocity, which increase the vibration of the vehicle; even the phenomenon of jump will occur when the amplitude of wheel polygonization is large enough.