An investigation into unsteady base bleed for drag reduction in bluff two-box SUVs

This paper discusses a preliminary investigation into the use of base bleed on a production SUV using CFD analysis. The paper shows the methods used in creating the computational model and conducting the analysis, and present the findings to date. The paper shows that the reduction in drag increases as the mass flow rate of air is increased when the flow is deflected at the outlet. By controlling the turbulent wake to the rear of the vehicle, it is shown in the paper that mass flow rates of under 2kg/s can reduce drag coefficient by 8.2% with an outlet on the side of the vehicle, and that a mass flow rate of under 1.5kg/s can reduce the drag coefficient by 10.7% for an outlet on the upper section of the rear of the vehicle. The paper also discusses the feasibility of base bleed being applied to a production vehicle.