Numerical Simulation of Hydrodynamic Noise of a Tire Driving on a Wet Road

When a tire drives on a wet road, the driving noise shows greater loudness and higher frequency than that on a dry road. The tire-road contact status and the crucial hydroplaning speed are strongly related to the driving noise on a wet road, but their relationships are only investigated by field observations. The hydrodynamic noise characteristics of a radial tire on a wet road were investigated based on the acoustic mechanism. The coupled Eulerian–Lagrangian (CEL) method was utilized for building the computational domain. The acoustic source was analyzed using the RNG k-ε turbulence model in conjunction with Large Eddy Simulation (LES), and the acoustic properties were simulated using the acoustic finite element method (FEM) combined with the automatically matched layer (AML) method. Numerical results showed the following: (1) For the tire with longitudinal patterns, the hydrodynamic pressure on the tire was proportional to the thickness of the water film and the speed, while the aerodynamic pressure was minorly affected by the water film. (2) The external radiation sound field of hydrodynamic noise was bidirectional and dipole. (3) The frequency curves of the hydrodynamic noises on a wet road with different thicknesses of water film, which peaked at the frequency of above 1,200 Hz, varied almost in the same way.