NUMERICAL SIMULATION ON AERODYNAMIC CHARACTERISTICS OF VEHICLES AND BRIDGES UNDER CROSS WINDS WITH THE CONSIDERATION OF VEHICLE MOVING

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 1, 2 and 3), the interaction mechanism of the aerodynamic forces between vehicles and bridges were discussed.