Investigation of a novel active flow control technology on the chronology of the dynamic stall of oscillating airfoils at low Reynolds number

Abstract

A numerical investigation is performed to determine the impact of an active flow control technology called the Co-Flow Jet (CFJ) on the chronology of the dynamic stall of oscillating airfoils at low Reynolds numbers. The models were validated by two experimental cases of oscillating airfoils. The modified baseline airfoil was examined at three jet momentum coefficients (Cμ = 0.16, 0.25, and 0.36). The results demonstrated that, when compared to the baseline airfoil, during the oscillation upstroke, CFJ causes a delay in the dynamic stall onset and vortices’ convection. Moreover, during the oscillation cycle’s downstroke, CFJ causes the flow to reattach earlier. that the flow reattached at angle 14.86° down stroke at all studied values of Cμ, while the flow was reattached at angle 9° in the case of the baseline airfoil. The CFJ airfoil produced a significant improvement in lift coefficient and a reduction in drag coefficient.