桥面典型车辆气动特性及车辆间挡风效应的数值模拟研究

强风不仅是大跨度桥梁设计的控制性因素，同时也会影响到桥上车辆运行的安全，车辆气动特性是研究车辆行驶安全性的前提。基于计算流体动力学（CFD）仿真平台，模拟计算了汽车工业研究协会（MIRA）小车和重型卡车典型车辆在横风作用下的气动特性，分析研究了典型车辆分别位于桥面上不同车道位置时车辆气动力系数随风偏角的变化情况；进一步模拟计算了重型卡车与小车之间的挡风效应，研究了车辆间相对位置对车辆挡风效应的影响。计算结果表明：不同车型以及不同的桥梁车道位置对车辆气动力均有不同程度的影响；重型卡车对MIRA小车有明显的挡风效应，MIRA小车气动力随着车辆间相对位置变化显著，重型卡车气动力也有一定改变。

NUMERICAL SIMULATION ON AERODYNAMIC CHARACTERISTICS OF TYPICAL VEHICLES ON BRIDGES AND THE WINDSHIELD EFFECTS BETWEEN VEHICLES

Strong wind is not only the control factor for the design of long-span bridges but also a significant factor affecting the driving safety of vehicles on the bridge. The aerodynamic characteristic of vehicles is the premise for studying the driving safety of vehicles. The aerodynamic parameters of motor industry research association (MIRA) cars and heavy trucks under cross wind were calculated based on the computational fluid dynamics (CFD) simulation platform in this paper. The variation of the aerodynamic coefficient of vehicles with the wind yaw angle is studied when typical vehicles are located in different lanes on a bridge. The wind sheltering effects between heavy trucks and MIRA cars were also studied. The influence of the relative positions of vehicles on the wind sheltering effects was studied. The results show that the types of vehicles or their locations on different lanes of the bridge have different degrees of influence on the aerodynamics of the vehicles. Heavy trucks have obvious wind sheltering effect on MIRA cars. The aerodynamics of MIRA cars change significantly with the variation of the relative locations of vehicles and the aerodynamics of heavy trucks do not change so much.