Computational Investigation into Disc pads Pressure Distribution and Thermomechanical Coupling Characteristics of Brake Pads in Disc Brake

Abstract:

Finite element model (FEM) of three dimensional transient thermo mechanical coupling dynamics was established for a ventilated disc brake, in which two rigid surfaces were used to simulate the normal force applications on both piston side and finger caliper side, with different shapes according to their respective structures. Based on this model, the contact pressure between the disc and the two pads, the thermo mechanical coupling characteristics of two pads were calculated under a certain emergency braking condition. The analysis results show that load transfer effect caused by friction force leads to the excursions of the pressure distribution center in the direction of entering friction area. However, the time varying contact pressure distributions on both sides are different, which are affected by brake structures, dynamical normal forces and friction forces, and the disc thermal distortion. The complicated temperature distribution of brake pads is caused by the varying frictional heat, the circular temperature gradients of the disc and the radial contact pressure gradients. The linings generate mainly pressure stress whose distribution is similar to that of contact pressure. The lining deformation patterns and their changes are strongly influenced by disc thermal distortion.