Aerodynamic Investigations of Vehicles under High Side Wind Conditions on Bridges
2022-01-1094
03/29/2022
- Content
- Vehicles with large side areas like busses or trucks are typically quite sensitive to side winds. This becomes especially important on bridges where the wind speeds are higher compared to the ground level and the vehicles are more exposed. The aerodynamics forces and moments created by the winds can severely affect the stability of the vehicle and even lead to possible rollover in extreme weather scenarios. Moreover, in the presence of bridge structures these forces can change relatively abruptly resulting in unstable vehicle behavior. This paper studies how aerodynamics loads change under different wind yaw conditions for various vehicles. The investigations include both Computational Fluid Dynamics (CFD) simulations and wind tunnel experiments using generic scaled models. The results from these two methods are compared and analyzed. Additionally, the effects of individual and combined bridge structures, e.g. the deck, pylons and wind barriers, are explored with a special focus on the vehicle passing the pylon wake. Several different modelling approaches are used for this investigation including steady-state Reynolds Averaged Navier Stokes (RANS) and unsteady simulations using overset mesh methodology. The computations are performed for 30, 60 and 90 degree wind yaw conditions. The results also include aerodynamic force coefficients for different wind shield heights, designs and porosity levels. Simulation and experimental results showed very similar trends with minor differences due to missing moving ground in the wind tunnel. The simulations showed that the bridge structures have high influence on the aerodynamic forces acting on the vehicles. The data obtained for various vehicles is currently being used for vehicle dynamics investigations to look into handling stability and driver behavior.
- Citation
- Vdovin, A., "Aerodynamic Investigations of Vehicles under High Side Wind Conditions on Bridges," SAE Technical Paper 2022-01-1094, 2022, .