车桥系统气动特性的节段模型风洞试验研究

侧向风作用下的车桥耦合振动分析需要考虑相互气动影响的车辆和桥梁各自的气动参数。为考虑车辆和桥梁的相互气动影响,在常规桥梁节段模型三分力测试装置的基础上研制了一种三分力分离装置———交叉滑槽系统。该系统利用环形滑槽和直线滑槽交叉点位置的变化来调整车辆和桥梁间的相对几何关系,并能实现车桥系统的同轴转动,从而方便地进行不同攻角情况下气动力的测试。利用交叉滑槽系统通过节段模型风洞试验对车桥系统的气动特性进行了多工况对比研究,讨论了车桥系统的雷诺数效应,分析了车桥间的相互气动作用,比较了车辆在桥上位置的影响。试验结果表明,基于交叉滑槽系统的节段模型风洞试验测试是可行的;车桥间的相互气动作用对车辆和桥梁的气动力有较明显的影响。

Study on Aerodynamic Characteristics of the Vehicle-bridge System by the Section Model Wind Tunnel Test

Under cross wind action, vehicle-bridge coupling vibration analysis requires consideration of aerodynamic force parameters of vehicle and bridge deck. In order to take aerodynamic interaction between vehicle and bridge into account, a separation device is developed on the basis of the routine bridge section model measure device, here called the Crossed Slot System. In the device, geometrical relationship between vehicle and deck can be easily adjusted by change of cross points between linear slot and circular slot. In addition, vehicle and deck can be rotated around the same axis for the tests with various wind angles of incidence. Using the Crossed Slot System, the aerodynamic characteristics of the vehicle-bridge system are measured by the section model wind tunnel test. Base on the test results, effect of Reynolds number on the vehicle-brdige system, aerodynamic interaction between vehicle and bridge, influence of geometrical relationship between vehicle and deck are analyzed. The analysis shows that the section model wind tunnel test based on the Crossed Slot System is practicable for aerodynamic force measurement of the vehicle-bridge system, and the effect of aerodynamic interaction between vehicle and bridge on the aerodynamic force of the vehicle-bridge system is notable.