高速走行時における車両下部音の音源別寄与度

摘要

In order to reduce Shinkansen noise, it is important to develop appropriate countermeasures for pantograph noise and the noise generated from the lower part of cars. The noise generated from the lower part of cars mainly consists of aerodynamic noise and rolling noise. In this paper, an attempt is firstly made to estimate the contribution of rolling noise quantitatively. Next, the contribution of aerodynamic noise to the total noise generated from the lower part of cars is determined by a comparison of measured noise and analytically estimated rolling noise. It is concluded that, above 335km/h, the aerodynamic noise has a much greater contribution to the total noise generated from the lower part of cars than the rolling noise.%現車試験の測定結果と転勤音予測法を用いて，新幹線の車両下部音における転勤音と空力音の寄与度の推定を行った。その結果を以下に整理する。（1）315km/h以下で列車が走行する場合，1600Hz以下の　周波数域において空力音が発生するが，車両下部音に対して大きな影響を与える音源は転勤音である。