Experimental and Numerical Modelling of Friction Induced Noise in Disc Brakes

<div class="htmlview paragraph">Friction-induced vibration is a serious problem in many industrial applications containing systems with rotating and/or sliding parts. Brake noise is a typical example. The critical element in the noise generation process is the combination of friction-induced loads with the dynamics of the braking system. In the present paper, a detailed experimental and numerical study of a specific low-frequency brake squeal problem is made on a simplified brake noise test rig.</div> <div class="htmlview paragraph">First, the signal and spatial characteristics of the noise were analyzed by spectral and acoustic holography techniques. A parametric study of influence factors as brake pressure, rotation speed, etc. was made. Operational deformation analysis during squeal confirms the dominant modal behavior of the components, implying the critical role of the assembly structural dynamics.</div> <div class="htmlview paragraph">Consequently, a detailed structural dynamics study (experimental modal analysis as well as finite element analysis) was made of the various brake system components. Furthermore, a multibody simulation model was developed for the assembly during braking, including a novel approach to model the contact between the moving and static components.</div> <div class="htmlview paragraph">The simulation models allowed to explain the various observations of the experimental studies and provided new insights in the squeal generation mechanism and the importance of the various influence factors.</div>