An experimental study on the brake squeal noise

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 an extensive set of measurements performed on a laboratory disc brake designed to provide a reliable tool for the study of the squeal noise. The experiments show the dependence of the squeal frequency on many parameters, such as normal load, wear of the pads, and relative velocity, providing a good basis for the development of a consistent model of the squeal phenomenon. The laboratory disc brake is designed and manufactured to evaluate the behavior of a real automotive brake. A reduced order model of the experimental set-up is developed The results show a very good agreement with the corresponding experiments and suggest a physical description of the squeal mechanism.