Investigation of sound radiation by automotive tyres vibrating at low resonant frequencies

In this work, the experimental study was conducted to identify the resonant frequencies and modal shapes of an automotive tyre. Further work was undertaken to determine the sound radiation characteristics of the tyre excited at these resonant frequencies. The obtained experimental results can be used for better understanding of the structural resonant behaviour of the tyre and of its sound radiation. A simple theoretical model was developed to describe sound radiation by tyre vibration modes. The model uses combinations of acoustic monopoles to represent a tyre vibrating over the first four modes of vibration. A good agreement was achieved between the normalised acoustic pressure plots predicted by the model and those measured in the anechoic chamber.