Fast Prediction of Disc Brake Squeal Uncertainty Based on Perturbation Concept

It is a worldwide technical difficulty to predict brake squeal uncertainty and its propagation regularity due to key parameters’ randomcity. However, as a widely used stochastic finite element method, Monte Carlo Method costs a large amount of time in calculation. It is very important to establish a fast prediction method for brake squeal uncertainty due to key parameters. In this paper, perturbation concept was applied for disc brake squeal uncertainty prediction. Firstly, a simplified, parameterized finite element model of disc brake was established for complex eigenvalues calculation. Then sensitivity analysis of real parts and frequencies of complex eigenvalues to influence parameters was carried out based on the finite element model. A series of second order perturbation polynomial formulas were fitted from the sensitivity analysis results, which were used for calculation of uncertain complex eigenvalues. The comparison between the results of Monte Carlo method and those of Perturbation method was done from the viewpoints of samples values, statistical values, probability density histograms and probability density curves. The comparison results show that the relative error of perturbation method to Monte Carlo method is less than 5%, and the calculation time is reduced to less than 5%, too. This indicates that the established uncertainty prediction method based on perturbation ideal is a satisfied object oriented brake squeal uncertainty method, which has higher precision and higher efficiency.