Crosswind effect studies on road vehicle passing by bridge tower using computational fluid dynamics

When a road vehicle moving on a bridge deck is passing by a bridge tower, the vehicle will be shielded briefly from the crosswind by the bridge tower. This study aimed to apply computational fluid dynamics to explore this special engineering problem for the first time. A stationary vehicle immerged in the wake of a bridge tower was first simulated and compared with wind tunnel test results. By using the dynamic mesh method, the moving of the vehicle passing by a bridge tower was then simulated. The results show that the computed aerodynamic coefficients of the stationary vehicle are generally larger than wind tunnel results. The side force and yawing moment coefficients of the moving vehicle are lower than those of the stationary vehicle. The results also show that the suddenly changing time of aerodynamic forces caused by the tower may be shorter than the average driver reaction time.