Dynamic Modeling and Vibration Analysis of Gearbox Bearings for a High-Speed Train With Polygonal Wheel

Gear transmission system (GTS) is an essential component of the traction system of high-speed trains (HSTs). Polygonal wear is a common wheel failure phenomenon during the operation of HSTs. The vibration behavior of bearings within GTSs excited by wheel polygonal wear (WPW) is not yet clear and rarely studied. The performance deterioration or failure of gear pair and bearings will affect train operation safety and even lead to serious accidents. Therefore, this article establishes a novel dynamics model of vehicle-track system with GTSs to master the dynamic behaviors of the bearings within gearbox. The wheelset flexible deformation is considered and performed using finite element method (FEM) and the modal superposition method. Importantly, the measured geometry of WPW is employed in the study, and the nonlinear contact and friction within bearings are considered. This novel modeling approach can predict the influence of wheelset elastic deformation and gear meshing excited by WPW on gearbox bearings. The established model is verified through comparative analysis with experimental data from HST field tests. On this basis, the vibration behavior of gearbox bearings is investigated with measured WPW at different running speeds. The findings underscore the imperative to meticulously account for elastic deformation of wheelsets caused by WPW across various speeds. Within specific velocity ranges, such deformations intensify the gear meshing and amplify the vibrations of the wheelsets. Consequently, these changes markedly influence the interactions and the vibrations of bearings within GTS.

I. Introduction

Gear transmission system (GTS) of a high-speed train (HST) delivers the torque generated by the motor to the driven wheelsets to generate tractive effort. Conversely, it also transmits the torque from the wheelset to the motor in a decelerating phase. GTSs are crucial to the running reliability and safety of HSTs. In operation, GTSs suffer the excitations from the driving motor and wheel-rail interfaces [1]. With the increasing running speed of HSTs in China, the excitations, including the driving motor and wheel-rail interface, become more severe [2], which affects the transmission stability and can lead failures of the transmissions, threatening operations, and running safety [3], [4]. Bearings are the weakest link within the GTS, and their dynamic behavior is extremely complex and difficult to monitor due to the enclosed structural environment in vehicle operation. Consequently, it is essential to investigate the dynamic behavior of bearings within GTS considering the excitations of driving motors, gear meshing, and wheel-rail interactions.