A Simulation-Based Parameter Study of Car Tyre Rolling Losses and Sound Generation
Paper in proceeding, 2012
Due to legislative changes within the EU there is an increased demand for improvements in car tyre rolling resistance and noise generation. Apart from measurement data, however, information about the relationship between rolling resistance and rolling noise generation is scarce. It is the goal of this study to investigate the fundamental physical processes connecting both areas. Additionally, it is evaluated whether a simultaneous reduction of both rolling resistance and rolling noise is possible or if this is contradicting requirement. A previously presented model for simulating the structural dynamics and rolling resistance of a rolling car tyre is extended to allow rolling noise calculation. The approach is based on a waveguide finite element model of the tyre. Tyre/road contact forces are obtained using a non-linear 3D contact model. The velocity field on the tyre surface is used to determine the radiated sound pressure based on a boundary element method. In a parameter study it is evaluated how much dissipation and sound radiation are affected by material properties, tyre construction and road surfaces. Due to the characteristics of the modelling approach, detailed information about dissipation and sound generation in different frequency regions, wave orders or parts of the tyre is available. The results show that rolling resistance and radiation are mainly low wave order, low frequency phenomena which are, at least partly, controlled by the same set of modes. This suggests that by modifying specific tyre properties reductions in both sound radiation and rolling resistance can be achieved.