S. Nacivet

Study of the nonlinear stationary dynamic of single and multi-instabilities for disk brake squeal

The focus of this paper is to show and discuss the nonlinear dynamical behaviours of brake system subjected to friction-induced vibration that can be generated due to the co-existence of multi-unstable modes. A finite element model with friction coupling is used to analyse the stability of the brake system and the stationary nonlinear oscillations for squeal noise prediction. The mechanism of squeal instability considers a mode coupling phenomenon that is classically referred to as coalescence.

Superelement Reduction of Industrial Finite Element Brake System for a Constrained Harmonic Balance Method

Brake squeal is a ubiquitous disturbance in automotive systems. Facing the complexity and the cost of experimental tests, simulations of brake squeal have become essential as well as to provide a predictive numerical method. Two major approaches exist in the numerical analysis of this phenomenon, the transient analysis and the complex eigenvalue analysis. In this study, the Constrained Harmonic Balance Method is applied on an industrial finite element system in order to estimate the nonlinear stationary responses due to friction induced vibration. This paper aims at explaining how a finite element system was adapted to the CHBM and at analyzing the results. First of all, the method used to reduce a finite element brake system is examined and the contact issue is particularly emphasized. Then, a brief summary of the CHBM is made. Finally, limit cycles are obtained close to the Hopf bifurcation.Copyright

A New Surrogate Modeling Method Associating Generalized Polynomial Chaos Expansion and Kriging for Mechanical Systems Subjected to Friction-Induced Vibration

This study focuses on a hybrid surrogate modelling technique in order to predict parameter-dependent mode coupling instabilities for uncertain mechanical systems subjected to friction-induced vibration. For this purpose, the most common strategy consists in associating a Monte Carlo procedure and/or a scanning technique together with the Complex Eigenvalue Analysis (CEA). This numerical strategy is computationally too prohibitive, particularly in an industrial context such as in the brake systems. To overcome this drawback, a novel approach is proposed. It consists in the combination of the generalized polynomial chaos (GPC) together with the kriging based meta-models. The association of both methods gives rise to a hybrid meta-model allowing taking into account two sets of uncertain parameters in the prediction of mode coupling instabilities. Moreover, it permits avoiding the use of the prohibitive MC and scanning methods. Thereby, this study analyses the feasibility of the proposed meta-model and its potential to be an efficient predictor of squeal propensity under parameter uncertainty.