LES of the Flow around Ahmed Body with Active Flow Control

Abstract

Three different activation strategies for active flow control around an Ahmed body are investigated using large eddy simulations. Both the separation region on the slanted surface and the cone-like trailing vortices were influenced using different actuation strategies. However, only one of the flow regions was influenced at a time. The actuation of the separation slant region was done using either constant blowing or periodic blowing and suction through the spanwise slot near the edge between the slant and the top of the body. Another actuation strategy used blowing of constant jets into the cone-like vortices with the objective to weaken them. The latter strategy was found to produce an increased drag in agreement with previous experimental data. Only the actuation strategy using constant blowing along the spanwise slot was found to decrease the overall drag on the body.