Tyre cavity noise: porous materials as a countermeasure

Tyre cavity resonance can significantly affect vehicle interior noise at frequencies around 200 Hz. The insertion of a sound absorbing liner inside a tyre is known to be an efficient countermeasure and tyre manufacturers are already producing tyres implementing this solution. The present work, through analytical and numerical models, supported by experimental tests, proposes a methodology for predicting the damping performance of a lined tyre. The geometry of the lining and the properties of the sound absorbing material are taken into account and predictions are made concerning the effect of specific combinations of volume and properties of the liner. For fixed material characteristics, the volume of the lining treatment strongly influences the attenuation of the cavity resonance. Moreover, the simulations performed suggest that for fixed volume and material properties, better cavity resonance attenuation can be obtained by adopting discontinuous layout.