Simulation study on noise reduction of electric vehicle tire with built-in sound-absorbing material

Tire cavity noise is becoming more prominent as the speed of electric vehicles is getting higher. This study aims to use a built-in sound-absorbing material to reduce tire cavity noise. First, the radial force was extracted by rolling analysis, and the tire cavity noise was obtained. Then, in order to investigate how the placement of sound-absorbing material affects the noise reduction, sound-absorbing material was applied to the inner side of tire’s side and tread position respectively. Finally, studies were done on the impact of sound-absorbing material’s density, flow resistance, porosity, and thickness on tire noise reduction. The best way to reduce noise with a 215/55R17 tire was to apply sound-absorbing material at side position. The density, porosity, flow resistance and thickness of the sound-absorbing material were 55 kg/m3, 0.95, 5000 Pa·s/m2 and 40 mm, respectively. The A-weighted sound pressure level decreased by 27.7 dB compared with that before the built-in sound-absorbing material. In response to the uncertainties on the reduction achieved by the sound-absorbing material, this study offers some recommendations for noise reduction of tire cavity. The studied effect is limited to the tire cavity, and the effect on the emitted sound energy has not been evaluated.