Large-eddy simulations of wind shear from passing vehicles under a freeway overpass

Large-eddy simulations of a vehicle ( an Ahmed body) moving under a freeway overpass at a distance of 0.75 w (vehicle’s width) from the bridge poles have been performed. Simulations outcomes include transient contours of mean velocity, turbulent kinetic energy, vorticity, and pressure around the vehicle, between the vehicle and the bridge poles, and at the bridge poles at different time steps. Results indicate the vehicle’s base pressure changes with time due to the impact of the poles' constraints on the vehicle's drag. On the bridge poles, the location of the stagnation point changes with the passing of the vehicle, and the poles experience a transient load, with the peak load associated with the passage of the vehicle's leading edge. The transient wind generated between the poles is mostly due to the vehicle’s front and decreases with the passing of the vehicle. The pressure at this location oscillates between a peak positive and a peak negative, generating a force potential for possible electric power generation. This data indicates the potential of capturing vehicle-generated wind energy for electric power generation, which could help California meet its clean energy goals and mitigate the negative impacts of climate change.