中文摘要：

车辆和桥梁气动力参数的准确识别是风一车．桥系统耦合振动研究的前提，目前大多数研究中通常忽略了车辆和桥梁间的相对运动。由于采用风洞试验测量手段研究此类问题存在一定困难，因此该文基于CFD数值仿真平台采用动网格技术模拟计算了横风作用下考虑车辆运动的车辆和桥梁气动特性，分析研究了风场的紊流特性、车辆的运动速度以及车桥的相互气动干扰对车辆和桥梁气动特性的影响。计算结果表明：车辆和桥梁的气动力特性受车辆的运动速度和车桥问的相互作用影响较大，风场的紊流特性对车辆和桥梁的气动力也有一定影响。最后通过对比分析单车、桥和车．桥耦合的流场压力和速度云图，探讨了车辆和桥梁气动力的相互作用机理。

英文摘要：

The exact identification of the aerodynamic characteristics of vehicles and bridges is the premise for the coupling vibration analysis of a wind-vehicle-bridge system. At present, the relative motion between vehicles and bridges was ignored in most researches. It is difficult for wind tunnel tests to simulate the moving of a vehicle and to measure the aerodynamic forces of vehicles and bridges under cross winds respectively. The aerodynamic characteristics of vehicles and bridges under cross winds with the consideration of vehicles moving are investigated by using the dynamic mesh method of computational fluid dynamics （CFD） in this paper. The dependence of aerodynamic forces on vehicle speeds was determined and the interaction of aerodynamic forces between vehicles and bridges and the influence of the turbulence were investigated. The results showed that the vehicle speed and the interaction of aerodynamic forces between the vehicle and bridge had great influence on the aerodynamic characteristics of vehicles and bridges. The turbulence also had some influence on the aerodynamic characteristics of vehicles and bridges. In the end, comparing and analyzing the pressure and velocity contour of the three cases （cases l, 2 and 3）, the interaction mechanism of the aerodynamic forces between vehicles and bridges were discussed.