Robust Stability Analysis of Brake Squeal Based on a Parametric Finite Element Model

Brake squeal is an instability phenomenon, which is severely dependent on many parameters. This study attempts to assess the effects of their variability on brake squeal behavior through FE computation. A detailed FE model of a commercial brake corner has been built up in order to predict its nominal squeal behavior. This analysis includes a non-linear preloading step to predict the system working-point and a complex eigenvalue analysis to assess its stability. A parametric study has been conducted in order to estimate the dependency with respect to the friction coefficient. The FE model has been parameterized to investigate the effect of variability. The process includes geometry simplifications to reduce CPU time, allowing far more configurations to be computed. Several parametric studies have been conducted to assess the effects of the friction coefficient, of the rotating direction, of the friction induced damping and of the hydraulic pressure. A numerical matrix test has been undertaken to synthesize the brake behavior in the wide variety of conditions it may encounter. Then, a full factorial design of experiments has been conducted with respect to the friction coefficient and the disc Young Modulus. This analysis shows biparametric coupling patterns and stability charts. Finally, it is possible to rank the parameters with respect to their influence and to assess the performance and the robustness of the system.