Estimation methods for aerodynamic noise generated from the bogie section of Shinkansen trains by using wind tunnel test

Abstract

A method has been developed for predicting the aerodynamic noise from the bogie of a high-speed train using a two-dimensional microphone array in a low-noise wind tunnel. First, the mean velocity distribution of flow was simulated precisely in the low-noise wind tunnel. Next, aerodynamic noise generated by the bogie, hereinafter referred to as aerodynamic bogie noise, was estimated from the noise source distribution measured with the two-dimensional microphone array. Finally, based on the experimental results, the predicted noise generated from the lower part of the car (i.e. the total of the aerodynamic noise estimated through the proposed method and the rolling and machinery noise estimated in a previous study) was compared with the measurement data obtained near the track in the field test. It was found that the predicted sound pressure level showed good agreement with those measured in the field test. This suggests that the proposed method is appropriate to estimate the aerodynamic bogie noise quantitatively. It was also shown that the contribution of the aerodynamic bogie noise to the total noise generated from the lower part of the car is greater than that of rolling and machinery noise, especially below 500 Hz.