Investigation of Driving Point and Transfer Mobilities of Simple Tread Blocks on a Tyre

An important issue when modeling noise generation from rolling tyres using the orthotropic plate tyre model [1] is to find accurate Green’s functions for the responses of the tyre. These Green’s functions are used to solve the tyre/road contact problem of the rolling tyre in the time domain. For tyres with tread blocks, it is important to consider the influence of the tread blocks on the response. It has previous been suggested that the tread blocks could be modeled as mass-spring systems [2]. Measurements of mobilies on a tyre with simple and regular tread blocks shows that this approach is unnecessary when modelling the response in radial direction of the tyre in the frequency range between 0 and 2500 Hz. Instead the tyre may be modeled, using a plate tyre model, as a soft plate with slightly higher local deformation. The tread pattern may be modeled in the tyre/road contact model as a macro roughness, where points at the blocks may be in contact with the road while forces at points in the groves are set to zero.