Thermal Structure Coupled Simulation And Life Prediction For A Disc Brake

The brake is a core component of automotive brake systems, which plays an important role for the safety performance of the automobiles. The disc brakes are widely used, so it has great significance to make deep study on the disc brakes. When braking, it is a typical thermal-structural coupling process and has a major impact on the thermal fatigue and the vibration of the brakes, which has a very important guiding significance in the design process of the brakes.In this article, it summarized the research status of the thermal-structural coupling of the disc brake and it also concluded the heat transfer of the rubbing surface. On the base of the law of the frictional heat generated between the disc brake and arrester as also as the distribution of heat flux, it established the finite element model. It imitated the braking process using the nonlinearity finite element software. In the theoretical calculation, it took the brake pressure, the frictional factor, material expansion coefficient and the boundary conditions of the heat convection into account.By means of the simulating and analyzing the themal-structural coupling process of the brakes, it obtained the transient temperature field, the contact pressure and the regularity of distribution of the themal stress field between the brake and the arrester when braking. In emergency conditions, the temperature field was distributed to non-symmetry axis. There is a large temperature difference on the radial direction and low temperature difference on the axle direction. With the brake process, the temperature field gradually became axial symmetry direction. Under the combined action between the friction heat and the heat convection, the maximum temperature of the contact surface appeared at the friction radius and became lower along the two sides. The heat stress is much larger than the mechanical stress and the maximum stress is at the friction radius.In this article, on the basis of the temperature field, the stress field and the contact pressure of the disc brake, it forecasted the thermal fatigue life of the disc brake with the Manson-Coffin and analyzed the factor which had influence on the brakes.