Effect of web hole on vibration noise radiation characteristics of railway wheel

Taking the common wheel of metro train in China as an example, 3D finite element models of none web hole, 4 web holes, 6 web holes and 8 web holes of wheel were developed using FEM software ANSYS. On the basis of wheel modal analyses by Block Lanzos method, the frequency response of wheel vibration was analyzed using modal superposition method. A boundary element model of wheel was presented by boundary element method software LMS Virtual. Lab Acoustics, and then the frequency response result of wheel surface vibration was input as velocity boundary condition, the radiation characteristics of wheel vibration noise were analyzed by direct boundary element method. The numerical results indicate that wheel web hole is beneficial to reduce the radiation efficiency of wheel vibration noise in 20~800 Hz, and the more number of web hole, the lower radiation efficiency of wheel vibration noise in the low and middle frequency, but higher radiation efficiency of wheel vibration noise in 800~2000 Hz. Meantime, the more number of web hole, the lower radiation power of wheel vibration noise in 250~450 Hz. In high frequencies above 1 000 Hz, wheel web hole can change the main frequency of radiation power of wheel vibration noise. The acoustic radiation field of wheel vibration noise is not a simply monopole acoustic field, and wheel web hole has a significant influence on the directivity of acoustic radiation field of wheel vibration noise.