Validation of closed-loop coupling disc brake model for squeal analysis

Disc brake squeal remains an elusive problem in the automotive industry and developing a model that will predict unstable squeal-noise dynamics with reasonable accuracy is in urgent need. In this paper, a two stage validation method of closed-loop coupling disc brake model for squeal analysis using complex eigenvalue analysis is presented. At component level, finite element (FE) models are verified through the comparison of FE calculation and modal test results. At the system level, optimization method is adopted. Experiment modal analysis of stationary disc brake system with brake line pressure and brake torques applied is conducted. Then an optimization process is initiated to minimize the differences between modal frequencies predicted by the stationary model and those from test. Thus model parameters more close to real situation are found. Unstable mode prediction results of validated model are compared with those from brake noise bench test. The validated model can predict most of the squeal frequencies and the real part represent the occurrences of squeal. The method presented in this paper is proven to be valid and effective.