顺向斜风作用下桥面运动车辆气动特性试验研究

顺向斜风对行车安全的影响不容忽略，为考查顺向斜风对运动车辆气动特性的影响，采用移动车辆模型风洞试验装置，针对缩尺比为1/20的车辆和桥梁模型，测试了顺向斜风作用下运动车辆的气动特性，讨论了风速、风向和风屏障等因素对移动车辆气动特性的影响. 结果表明:移动车辆的五分力系数在不同风速时吻合较好；侧向阻力系数、升力系数和点头力矩系数随着合成风偏角的增大而减小；风偏角较小时，风向角对车辆的升力系数有较明显的影响；风屏障使车辆的气动力系数接近0，且明显地改变了车辆气动力系数随风偏角的变化规律；设置风屏障后，车辆阻力系数的变化率受风偏角、车速和风速等条件的影响. 

Wind Tunnel Tests on Aerodynamic Characteristics of Moving Vehicles on Bridge Decks under Skew Tail-Wind

The effect of skew tail-wind on driving safety cannot be ignored. To investigate the effect of skew tail-wind, the aerodynamic characteristics of the vehicle under the action of skew tail-wind were tested by using a wind tunnel test device of the moving vehicle model, aiming at the vehicle and bridge models with the scale ratio of 1/20. The effects of wind speed, wind direction and wind barrier on the aerodynamic characteristic of moving vehicle were discussed. The results show that the five-component coefficients of moving vehicle well agree with different wind speeds. The lateral drag coefficient, lift coefficient and nodding moment coefficient decrease with the increase of the yaw angle. The skew tail-wind has a significantly effect on the lift coefficients when the yaw angle is small. The wind barrier makes the aerodynamic characteristics of the vehicle close to 0, but it obviously transforms the change law of the aerodynamic coefficient of the vehicle with the yaw angle. After the wind barrier is installed, the change rate of drag coefficient of vehicle is affected by the yaw angle, vehicle speed and wind speed.