The Generation and Evolution of High-Order Wheel Polygonal Wear from the Effects of Wheelset Rotation

Polygonal wear affects driving safety and drastically shortens a wheel’s life. This work establishes a wheel–rail coupled system’s rotor dynamics model and a wheel polygonal wear model, taking into account the wheelset’s flexibility, the effect of the wheelset rotation, and the initial wheel polygon. The energy approach is applied to study the stability of the self-excited vibration of a wheel–rail coupled system. The wheel polygonal wear generation and evolution mechanism is revealed, along with the impact of vehicle and rail characteristics on a wheel’s high-order polygon. The findings demonstrate that wheel polygonal wear must occur in order for the wheel–rail system to experience self-excited vibration, which is brought on by a feedback mechanism dominated by creepage velocity. Additionally, the Hopf bifurcation characteristic is displayed by the wheel–rail system’s self-excited vibration. Wheel polygonal wear is characterized by “fixed frequency and integer division”, and the wheelset flexibility largely determines the fixed frequency of high-order polygonal wear, which is mostly unaffected by the suspension characteristics of the vehicle. By decreasing the tire load, increasing the wheelset’s damping, and choosing a variable running speed, the progression of polygonal wear on wheels can be prevented. Future investigations on the suppression of wheel polygonal wear evolution can be guided by the results.