Abstract: The standard wheel of model CRH3 high-speed train was taken as the study subject. The radiation noise of a single wheel under a vertical unit force excitation was calculated by acoustic Boundary Element Method (BEM). Then a new damped wheel with web-mounted noise shielding was introduced. The sound characteristics of both wheels were analyzed contrastively. Detailed boundary conditions were taken into consideration in studying the wheelsets rolling noise distribution on the coach surface. First, Multi-body Dynamics (MBD) was adopted to extract the wheel-rail interaction forces at the speed of 350 km/h. Then, a vibro-acoustic coupling model with four wheelsets was established. The results show that sound field of a single wheel reveals an evident directivity with petaloid variation by angle and continuous decrease by distance; and the wheel tread and web contribute the most rolling noise. Compared with the standard wheel the acoustic power of the damped wheel decreases significantly, especially at the peak frequency. The sound field of four wheelsets, which mainly distributes at the end of the coach and maintains the basic directivity, is formed under a composite overlap and interference effect between multiple wheel noise sources. Finally, a sound pressure spectrum comparison at an observation point indicates that the peak value of the standard wheel noise is mostly below 110 dB, while the total sound pressure level of the damped wheelsets is reduced by 15 dB, therefore, the noise reduction effect of the wheelsets is quite satisfactory.

Key words: damped wheel, wheelsets, rolling noise, acoustic boundary element method, multi-body dynamics