The contribution of air-pumping to tyre/road noise

Paper in proceeding, 2013

It is generally accepted that there are at least two tyre/road noise generation mechanisms commonly referred to as tyre vibrations and air-pumping. While the modelling of tyre vibrations is rather mature, the modelling of air-pumping is still on a basic stage and unsatisfactory in many aspects. Applying the fact that tyre vibrations and air-pumping have different vehicle speed dependency allows for identifying the contribution from each mechanism in field measurements of tyre/road noise. This paper presents an analysis of controlled pass-by measurements and simulations with the tyre/road simulation model at Chalmers. Results show that air-pumping is a major contributor to tyre/road noise. The question arises which physical mechanisms are behind the air-pumping noise observed in measurements and simulations. The analysis indicates that tyre vibrations in the contact may lead to air-pumping noise. This suggestion deviates from generation mechanisms usually assumed in the air-pumping context.