Integration of microscopic simulation of frictional contacts and macroscopic system dynamics into models of brake squeal.

• Applicant: Professor Dr.-Ing. Utz von Wagner
• Subject Area: Mechanics
• Term: from 2014 to 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 253211334

Friction induced vibrations of brake systems resulting in brake squeal are still a major problem for the automotive industry. Brake squeal is one of the most mentioned problems in customer surveys. The usual development process of brake systems includes time consuming experiments and most of the calculations are done with finite element models having many degrees of freedom. The noise simulations have not reached the state of a predictive tool in the development process. In most cases a noise problem observed in experiments is only reproduced in an adjusted simulation afterwards. To improve the predictive character of these simulations the following interrelated investigations are planned:Development of a calculation procedure for friction forces applicable to heterogeneous materials. The procedure is base of the method of dimension reduction.Due to the dimension reduction in the context of calculation of the friction forces it is possible to combine these calculations in a dynamics simulation of the complete system (hybrid model). The development and testing of hybrid models is one of main innovations of the present investigation.Further development (based on the results of first proposal) of a nonlinear brake model und investigation of its bifurcation behavior using methods of invariant manifolds.Investigations of active and passive counter measures to influence the self-excitation in the context of nonlinear phenomena. This includes the analysis of the influence of parameters, parameter-excitations and shims.

• DFG Programme: Research Grants