Mechanism research and structure optimization of brake noise based on contact overlap degree

Brake noise can endanger the psychological and physiological health of passengers, as well as cause noise pollution. Therefore, it is important to suppress the noise from the design stage of the braking system. Based on the establishment of a complex modal finite element model of the brake and verification of the validity of the model through bench test, the mechanism of “contact overlap degree” is proposed, that is, the influence of the brake disc-block friction contact overlap degree on the brake noise. In order to better simulate the real situation during brake friction contact, a face-spring distributed contact model of the brake is developed and the key influencing factors of contact overlap degree are selected. Based on the asymmetry and unevenness of contact overlap degree distribution, the structural optimization schemes of brake backplane and friction lining are proposed respectively, and the complex modal analysis is re-performed. The analysis results show that the noise incidence is reduced after structural optimization, which verifies the effectiveness of the above two structural optimization schemes in reducing brake noise. </jats:p

Thermal Stress Coupling Analysis of Ventilated Disc Brake Based on Moving Heat Source

There is a thermomechanical coupling phenomenon in the braking process of vehicle disc brakes. Since the solution time of the direct coupling method is long and it is hard to converge, it is not suitable for analyzing heavy-load braking conditions with long braking time. Meanwhile, the sequential coupling method based on fixed heat source cannot achieve the rotation of friction heat source of the brake disc or accurately simulate the change of temperature. Therefore, Abaqus user subroutine is invoked to achieve the heat source rotation. The results of the simulated temperature field are compared with the results of the complete thermodynamic coupling method, the sequential coupling method based on fixed heat source and dyno test. The comparison shows that the new method combines the advantages of the first two methods and has a better engineering value

Impact Analysis of Brake Pad Backplate Structure and Friction Lining Material on Disc-Brake Noise

This study proposes a three-layer brake pad design, on which a six-DOF dynamic model of brake disc-brake pad is established, and the factors affecting the system instability are analyzed. The analysis shows that the change of mass and stiffness of the brake pad will affect the stability of the system. From the linear complex eigenvalue analysis, the unstable vibration modes of the brake system are predicted, and the effectiveness of the complex mode analysis model is verified by the brake system bench test. Brake pads with different structural shapes are designed, and their influence on the stability of the brake system is analyzed. The results show that the design of the three-layer structure and the slotting design of the brake pad can effectively reduce the occurrence of the brake squeal, especially that of the high-frequency squeal noise