A Study of Drum Brake Squeal Using Complex Eigenvalue Analysis

摘要

Brake squeal having the range, about 1 kHz to 18 kHz, is generated when complex modes of brake components are coupled with the friction forces between drum and friction material. Due to the increasing warranty cost, though brake makers have been investigating the cause of squeal noise, there is no exact solution till now. In this paper drum brake squeal noise is predicted by complex eigenvalue analysis with finite element analysis. To predict the squeal phenomenon each finite element model of brake components has been organized and contact stiffness condition has been investigated. The analysis shows the mode coupling among drum, backing plate and lined shoes for each predicted squeal frequency. This result was compared to that of noise dynamometer test and a good agreement was found between analysis and test. Also using DOE(design of experiment), the effectiveness of each control factor was analyzed and finally optimized model for drum brake system was proposed. The optimized system has a good correlation through noise dynamometer test.