Large-Eddy Simulation for vehicle aerodynamics in unsteady crosswind condition

摘要

For a study on unsteady vehicle aerodynamics and its evaluation method, two different large-eddy simulations of flow around a vehicle in unsteady yaw conditions are conducted and the results are compared. A numerical boundary model, which represents an oscillating crosswind, and ALE method, which simulates oscillating yaw motion of the vehicle, are applied in the simulation. The both results show unsteady aerodynamic forces acting on the vehicle. However, ranges and sequences of the fluctuations have some discrepancies. Regarding unsteady effects, these results indicate an significant difference between crosswind and yaw rotation in spite of the same oscillating yaw angle.