Numerical Analysis of Mechanism of Aerodynamic Noise Reduction in Bogie Area by Rounding Corners of Bogie Cavity

Abstract

Aerodynamic noise radiated from high-speed trains in operation is attracting attention from an environmental point of view. Bogie areas are known to be the main sources of the aerodynamic noise. Rounding the four corners of the bogie cavity has been proposed as a measure to reduce bogie aerodynamic noise, and wind tunnel tests have confirmed its effectiveness. However, detailed flow fields around the bogie area have not been identified and the mechanism of noise reduction by such measures remains unclear. In this study, numerical analyses of the flow field in the vicinity of the bogie area were carried out to investigate the changes in the flow field caused by the proposed measure and to discuss the reduction mechanism.