Tyre/road interaction noise—Numerical noise prediction of a patterned tyre on a rough road surface

The noise which results from the interaction of pneumatic tyres with a rough road surface is a significant contributor to an increasing local environmental problem. Above a steady forward vehicle speed of 40 km/h this is the dominant noise source of a modern car in good working condition, and is a significant contributor to the overall radiated noise during acceleration.In order to determine the noise produced by a patterned tyre rolling on a rough road surface, the vibration characteristics of the tyre must be known. A method has been presented by O’Boy and Dowling [Tyre/road interaction noise: a 3d viscoelastic multilayer model of a tyre belt, Journal of Sound and Vibration, volume 322, issues 4–5, 22 May 2009, pages 829–850] which provides these vibration characteristics for a tyre belt composed of multiple viscoelastic layers, each layer having a different thickness and material properties. In this paper, we use this model of the tyre belt to determine the parameters of an equivalent simple bending plate model which can be adapted to yield the response of a tyre which includes sidewalls.A method is then described which uses this response to determine the acceleration of the tyre surface as it rolls over a rough road. These accelerations are then used to predict the far-field radiated noise for a patterned tyre on two rough road surfaces. Comparisons with experimental data are provided at each stage.