Numerical analysis of squeal instability

The name “brake squeal” groups a large set of high frequency sound emissions from brake systems, generated during the braking phase and characterized by a periodic or harmonic spectrum. This paper presents two different numerical approaches to identify the mechanism bringing to the dynamic instability, producing squeal noise. The first approach performs a finite element modal analysis on the brake system, to identify the eigenfrequencies of the components and to relate them to the squeal frequencies. The second one uses a specific finite element program, Plast3, appropriate for non-linear dynamic analysis in the time domain and particularly addressed to contact problems with friction between deformable bodies. The use of this program allows to verify the behavior of the components and to link results obtained from the time analysis and the modal one. The study presented is carried on a simple model, composed by a disc, a small pad and a beam supporting the pad, to simplify the behavior of its components