Simulation of Flow around a Generic Pickup Truck with RSM Model 2008-01-0324

Computational fluid dynamics (CFD) was used to simulate the flow field over a pickup truck. The simulation was based on a transient state formulation and the focus of the simulation was to assess the capabilities of the current RSM (Reynolds Stresses Model) in CFD tools for vehicle aerodynamic development for pickup trucks. Detailed comparisons were made between the CFD simulations and the existing experiments for a generic pickup truck. It was found that the flow structures obtained from the CFD calculations are very similar to the corresponding measured mean flows. Furthermore, the surface pressure distributions are captured reasonably well by the CFD analysis. Comparison for computational results was carried out for both linear Pressure Strain model (Launder, Reece and Rodi, 1978) and Quadratic Pressure Strain model (Speziale, Sarkar and Gatski, 1991). The CFD results of Linear and Quadratic RSM are very close to the test data. The CFD analysis of the two RSM models gives similar results for aerodynamic drag, lift and pressure coefficients. This suggests that RSM model can be used to aid the aerodynamic development of pickup trucks and that quadratic model does not do better than linear model as to the distributions of pressure and average velocity.