On the Wear Dependence of Low-Frequency and High-Frequency Brake Squeal 2018-01-1902
The dynamics of disc brakes and their NVH behavior in particular, have long been the focus of research. Measurements by Rhee et al. show that brake pad wear has a significant influence on the occurrence of low and high frequency squealing . It is suspected that low frequency squealing is more likely to occur when the wear difference between the inner and outer brake pads is high. If the two pads incur comparable wear, however, the prevalence of high frequency squealing increases.
In order to investigate this hypothesis, this paper focuses on a simplified model of a commercial brake system. First, the friction force between the inner pad and the disc is iteratively adjusted, while the force between the outer pad and the disc is held constant. In a second step, the inner pad’s wear is iteratively increased, while the wear on the outer pad remains unaffected. With the aid of the Complex Eigenvalue Analysis (CEA), the real part of the eigenvalue is used as a quantification measure in order to investigate the dependence between wear and high and low frequency squealing.
 Lee, S., Jeon, J., Kim, S., Kim, S. Rhee, S. et al. "A Study of Low-Frequency and High-Frequency Disc Brake Squeal," SAE Int. J. Passeng. Cars - Mech. Syst. 9(3):1235-1244, 2016, doi:10.4271/2016-01-1944.
Johannes Otto, Georg Ostermeyer, Seong Rhee