A modelling methodology of the axle box bearing-vehicle coupled system dynamics

Abstract

The axle box bearing serves as a critical rotational component for high-speed trains. Thus, it is of great significance to obtain accurate loading conditions for axle box bearings for its reliability design. In this study, a bearing-vehicle coupled system dynamic model, consisting of an equivalent bearing model characterized by the time-varying stiffness in the bearing, a nonlinear high-speed train dynamic model, and a slab track model, is developed. The validity of the proposed coupled dynamic model is demonstrated by comparing the simulated results with those obtained in a field test and the literature, respectively. Subsequently, the influence of long- and short-wavelength irregularities on the dynamic responses of bearings is investigated using the proposed coupled model in terms of dynamic loads of the axle box bearing. The results obtained by the proposed model are further compared with those calculated using a traditional vehicle dynamic model that represents the bearing as a revolute joint, so as to illustrate the advantages of the proposed model. The results suggest that the loading responses of the bearing calculated by the two models exhibit differences, which are simultaneously related to the structural damping of the bearing and the mode frequency change of the system.

KEYWORDS:

• Axle box bearing
• bearing-vehicle coupled system dynamic model
• time-varying stiffness of axle box bearing
• loading conditions
• high-speed train

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The present work has been supported by the National Science Foundation for Young Scientists of China (No. 52202464), National Science Foundation of China (No. U21A20168), China Association of Science and Technology Young Talent Support Project (No. 2019QNRC001), and Sichuan Science Foundation (No. 2022NSFSC0469).