Abstract
Rolling noises have become an important problem of narrow-gauge railway vehicles. The noises are composed of rail noise and wheel one. By the study about the wheel noise that we performed till now, We found that the noise radiated from wheel was not only the wheel web but also the other parts. Therefore, we carry out a more detail 3D-modal analysis experimentally for a purpose of inspecting the mode shapes obtained from FEM analysis and calculated the sound power separately from each part of the narrow-gauge wheels by using 3D-BEM analysis. Furthermore, we performed modify of the wheel geometry to examine an acoustic effect. As a result, we found that the wheel which added to the thickness of the rim has the lowest sound level compared with other wheels.