Friction and vibration behaviours of high-speed train brake system excited by wheel flats

To study the interface friction and vibration behaviours of brake systems with wheel flat, a rigid-flexible vehicle dynamics model and a finite element model of brake system are developed. These two models are validated using experimental test data. Additionally, an analysis formula of brake system excited by wheel flat is proposed to reveal the tribological behaviours. The results indicate that the wheel flat directly induces the elastic vibration of brake disc and further affects the disc contact, resulting in a significant increase in the contact force, contact stress, friction force and vibration acceleration between the brake interfaces. Furthermore, the proposed model can be used to investigate the related tribological behaviour of brake systems under other complex wheel-rail excitations.