高速列车车厢连接处脉动压力分析与控制

Analysis and control of the fluctuation pressure at inter-coach space of high-speed train

高速列车的表面湍流脉动压力和近场声压会影响车内的噪声。为了了解并降低车厢连接处的湍流脉动压力,制作了一个高速列车1:40缩比的两车编组模型,使用表面传声器和激光粒子测速仪得到车厢连接处的脉动压力和流场分布。通过试验发现,有受电弓时,车厢连接处前后测点的脉动能量分别为速度的5.07次方和5.19次方;无受电弓时,对应的脉动能量分别减少到速度的3.90次方和4.45次方。对于车厢连接处进行优化时,无论是否有受电弓,对车厢连接处进行全封闭处理均能够较好地降低其脉动压力、涡量和湍流强度。无受电弓时,在车厢连接处前端增加扰流球可使其前后方测点的湍流脉动总压力级分别降低0.6dB(A)和0.8dB(A)。有受电弓时,在车厢连接处前端增加扰流柱可使其后方测点的总湍流脉动压力级降低0.8dB(A)。

The surface turbulent fluctuation pressure and the near-field sound pressure of the high-speed train affect the interior noise. In order to understand and reduce the turbulent fluctuation pressure at inter-coach space, a two-coach connecting model for the 1:40 contraction ratio of high-speed train is made. The surface microphones and the laser particle velocimetry are used to obtain the fluctuation pressure and flow field distribution at inter-coach space. According to the experimental results, it is found that the fluctuation energies at the measuring points before and after the inter-coach space are respectively 5.07 power and 5.19 power of the speed for the train with pantograph, but for the train without any pantograph, they are reduced to 3.90 power and 4.45 power of the speed respectively. For the optimization at the inter-coach space, no matter with or without pantograph, the full closure of the inter-coach space can well reduce the turbulent fluctuation pressure, vorticity and turbulence intensity. Adding spoiler balls at the front end of the inter-coach space can reduce the total turbulent fluctuation pressure level at the front and rear measuring points by 0.6 dB (A) and 0.8 dB (A) respectively when there is no pantograph. But adding spoiler pillars at the front end of the inter-coach space can reduce the total turbulent fluctuation pressure level at the rear measuring point by 0.8 dB (A) when there is a pantograph.