The Impact of Wheelset Eccentricity on High-Order Polygonal Wear Based on the Theory of Frictional Self-Excited Vibration.

According to investigation, the wheelset generally appears in a mass eccentric condition. Therefore, the finite element model of a wheelset-track system with mass eccentricity was established in this study to investigate the dynamic response characteristics based on the frictional self-excited vibration theory. The research results show that, when the frictional self-excited vibration of the wheelset-track system occurs, the unstable vibration characteristics of the wheelset-track system corresponding to different dynamic imbalance values are almost the same. That is, the magnitude of the dynamic imbalance value has little influence on the frictional self-excited vibration of the wheelset-track system. Simultaneously, from the perspective of the excitation frequency f of the wheel polygonal wear, it shows a trend of increasing frequency with an increase in the running speed. Ultimately, as the phase difference in mass eccentricity grows, pronounced instability becomes evident within the mid- to high-frequency ranges once friction-induced self-excitation arises in the wheelset-track system. This condition readily promotes high-order polygonal wear on the wheel surfaces.