Asynchronous Longitudinal Vibration of the Wheelset System

Abstract

The longitudinal flutter of the wheelset system has caused abnormal wear of the wheel-rail and stripping of the tread surface, resulting in complex dynamic problems of the locomotive. And asynchronous longitudinal vibration of the wheelset could bring about different wear problems of the left and right wheels when the wheelset system was in some non-ideal working conditions. The longitudinal vibration model of the wheelset considering the effect of bending moment is established to obtain the equivalent force, which can carry out the vibration response simulation analysis of the left and right wheels , meanwhile, the irrational influencing factors are discussed. The results show that the system is stable when the creep rates of the left and right wheels are lower than the critical creep rate, otherwise, it will produce self-excited vibration. The analysis of the influencing factors of self-excited vibration indicate that the larger displacement of the center of mass of the wheelset will lead to the larger dynamic load in the system, increasing the vibration amplitude of the wheel on the offset side. And the vibration amplitude and velocity of the one with smaller primary longitudinal stiffness will increase, while the other one wheel will decrease. However, the wheel eccentric load is almost no effect on the longitudinal vibration amplitude.