The test and analysis of car's brake noise

Abstract

With the development of the car industry and the rising of consumer's requirements for comfort, brake noise gradually becomes one of the important factors to appraise the comfort of vehicle. This paper, aiming at solving the noise problem of the passenger car, researches the mechanism of brake noise's generation and the ways to optimize it in order to reduce the noise. The brake noise is tested according to the road test standard. The frequency and intensity of the noise are recorded in the vehicle test. At the same time, the relation of speed and the noise's frequency is recorded. The brake noise is divided into Squeal noise and Groan noise based on the test results of the car. Squeal noise: It is important to collect more information in the dynamometer which used suspension assembly to analyze the character of noise. The noise mechanism is analyzed and the optimum direction is found through the computer CAE technique. Groan noise: Based on the calculation and analysis of the test results, the main influencing factors of the noise are found and the optimum scheme is designed. Finally the performance of brake noise is validated in the dynamometer and the vehicle test. Computer analysis and test results show that Squeal noise is caused by the resonance of the brake system. In this paper, brake noise is reduced by reducing the stiffness of the brake disc by an average of 5%, optimizing the inherent character of the brake system and improving the stability of the brake system. Based on the test and the analysis, the main cause of the Groan noise is that the structure of brake pad and brake disc's ventilation is designed with defects. Groan noise is related to the structure of brake pad and brake disc's ventilation. It is effective to reduce noise by optimizing brake pad's structure. © Springer-Verlag 2013.