California is moving toward a 100% clean energy future, and expanded wind energy will be a major component of the state’s future energy portfolio. Innovations in wind energy resources will move California closer to achieving its goal. To gain a better understanding of transient pressure and the wind shear generated at the bridge poles from passing vehicles, this study performed large-eddy simulations of a vehicle (also called an Ahmed body) moving under a freeway overpass at a distance of 0.75 w (width) from the bridge poles. Results include transient contours of mean velocity, turbulent kinetic energy, vorticity, and pressure around the vehicle and at the bridge poles at different time steps. Additionally, results indicate the vehicle’s base pressure changes with time, indicating 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.

Publication Date


Publication Type



Planning and Policy, Sustainable Transportation and Land Use, Transportation Engineering

Digital Object Identifier


MTI Project



Large-eddy simulation, Turbulent shear, Aerodynamics, Vehicle's drag, Fluid-structure interaction


Environmental Engineering | Transportation | Transportation Engineering