Computational analysis of active flow control to reduce aerodynamics drag on a van model

Method of active flow control can be applied to reduce aerodynamic drag of the vehicle. It provides the possibility to modify locally the flow, to remove or delay the separation position or to reduce the development of the recirculation zone at the back as well as the separated swirling structures around the vehicle. In this study, a passenger van is modeled with a modified form of Ahmed's body by changing the orientation of the flow from its original form (modified/reversed Ahmed Body). This model is equipped with suction and blowing on the rear side to comprehensively examine the pressure field modifications that occur in order to modify the near wall flow toward reducing the aerodynamics drag. The computational simulation used is k-epsilon flow turbulence model. In this configuration, the front part of body was inclined at an angle of 35° with respect to the horizontal. The geometry is placed in a 3D-rectangular numerical domain with length, width and height equal to 8l, 2l and 2l, respectively. The suction and blowing velocities are set to 1 m/s, 5 m/s, 10 m/s and 15 m/s, respectively. The results show that aerodynamic drag reductions close to 15.83 % for suction and 14.38 % for blowing have been obtained.