风屏障在中国帽型突变风与列车风耦合作用下的气动响应

Aerodynamic Response of Wind Barrier under Coupling Effect of Chinese-Hat Sudden Wind and Train Wind

建立了风屏障在突变风与列车风耦合作用下的三维仿真模型,分别研究了透风率为30%的风屏障在横风、突变风及车致脉动风耦合作用的气动响应,分析了其表面的气动压力分布特征及原因.结果表明,风屏障受到横风与车致脉动风耦合作用时,车致脉动风产生的压力对风屏障起主要作用,横风作用减小了风屏障所受头波的正压峰值,增大了其尾波的负压峰值.当风屏障在受到突变风(风速平均值13.8 m/s)与车致脉动风耦合作用时,风屏障所受的压力比横风(风速13.8 m/s)作用下大得多,情况复杂也得多,风屏障所受的头波正压峰值扩大了9.7倍,尾波负压峰值扩大了2.4倍,气动压力变化率增大了2.5倍,持续作用时间增大了2.4倍.

The three-dimensional numerical model of the wind barrier under the coupling effect of sudden wind and train wind was established, and the aerodynamic response of the wind barrier with a ventilation rate of 30% under the coupling effect of constant wind, sudden wind and pulsating wind caused by the vehicle was studied respectively. The distribution characteristics and causes of aerodynamic pressure on its surface were analyzed. The results show that the pressure on the wind barrier generated by the vehicle-induced pulsating wind plays a major role when the wind barrier is coupled by constant cross wind and vehicle-induced pulsating wind. The constant cross wind reduces the peak positive pressure of the head wave and increases the peak negative pressure of the tail wave. When the wind barrier is coupled by the sudden wind(with the mean wind speed 13.8 m/s) and the train wind, the pressure on the wind barrier is much bigger and more complicated than in the constant cross wind(with the speed 13.8 m/s). The peak positive pressure of the head wave and the peak negative pressure of the tail wave increase by 9.7 times, the change rate of aerodynamic pressure increase by 2.5 times, and the duration of action by 2.4 times.