高速列车司机室内气动噪声预测

为了降低司机室内的噪声,采用大涡模拟法计算了高速列车车头曲面的脉动压力,将脉动压力作为头车司机室有限元分析的激励载荷,通过谐响应分析求得司机室壁板的振动速度,将振动速度作为司机室声场边界元模型的激励条件,求出了司机室内的气动噪声在不同频率点的声压分布。计算结果表明:司机室内的声压级在52·3~58·8dB(A)之间变化,声压级较大点位于司机室前窗玻璃向车顶过渡处及纵向中截面型线附近,且在50~315Hz之间,声压幅值较大;司机室内的气动噪声主要是低频噪声,对纵向中截面型线采取更平滑的过渡形式,可降低司机室内的气动噪声。

Prediction of interior aerodynamic noise of high-speed train cab

In order to decrease the noise in train cab, the fluctuation pressures of head curved surface of high-speed train were calculated by using large eddy simulation method, which were exerted on the finite element model of train cab as excitement load, the vibration speeds of cab plates were obtained by using harmonic response analysis, and were taken as the excitement condition of acoustic boundary element model of train cab, and the interior aerodynamic noises at different frequencies were attained by using acoustic analysis. Computation result shows that the aerodynamic noises levels in cab change from 52.3 to 58.8 dB(A), at the transitional place from cab windowpane to train roof and near the largest outline of head longitudinal section, the noise press level (SPL) of field points are greater, the noises are dominant ranging from 50 to 315 Hz; the aerodynamic noises in cab are low frequency noises mainly, if the largest outline of head longitudinal section is smoother, the noises will be reduced. 8 figs, 11 refs.