Vibration analysis of the axle bearings considering the combined errors for a high-speed train

Axle bearings are critical elements of high-speed trains. Although the quality and precision of axle bearings have been significantly improved, the manufacturing errors, such as the roundness and waviness errors, cannot be eliminated during their manufacturing processes. The axle bearings with the roundness and waviness errors have great influences on vibration performances of the high-speed trains. To obtain an in-depth understanding of the vibrations caused by the axle bearing with the combined errors considering both the roundness and waviness errors. This work conducts an improved analytical model for a high-speed train considering the axle bearings with the combined errors, which cannot be formulated by the previous train model considering single roundness or waviness errors. The combined errors are defined to include both the roundness and waviness errors. A new multiple cosine function is presented to model the combined errors. The time-depended force excitations produced by the combined errors are also considered in the dynamic model. A track irregularities model is utilized to formulate the road spectrum displacement excitations from the rail and roadbed. The influences of the error amplitude and order on the vibrations of high-speed train are analyzed. The results for the single roundness error model, single waviness error model, and combined errors model are compared to represent the superiority of proposed model. It depicts that this work can provide a more reasonable analytical method for understanding the vibrations of high-speed train considering the axle bearings with the combined manufacturing errors compared to the reported single error models.