Case study: Disc-brake squeal noise reduction through material selection and robust shape optimization

This work aims at numerically quantifying and minimizing disc-brake squeal noise occurrences, using a two-step process involving a material parameter study and shape optimization under uncertainties. Special attention is given to the minimization of computational cost. A simplified disc-brake model is constructed using the novel Isogeometric Analysis method which yields an original shape description well-suited to shape optimization. The prediction of squeal noise propensity is based on the fact that squeal noise is directly related to dynamical instability. A parametric study is carried out to select a material which minimizes noise. This material is then retained for the second noise reduction step which consists in optimizing the shape of the system, while maximizing robustness to manufacturing uncertainties. The conservative modeling strategy is a good compromise for squeal occurrence prediction while maintaining reasonable computational cost. The parameter study reduces noise potentiality by up to 10% and the shape optimization step yields a Pareto front of shapes which balance robustness and low noise propensity, with up to 16% noise reduction.