Experimental Investigation on Aerodynamic Performanceof Serrated Gurney Flap

Force and PIV local flow measurements were conducted in a low speed wind tunnel to study the effectiveness of serrated Gurney flap at different deflections. The results showed that the serrated Gurney flap could significantly increase the lift coefficients and the ratio of lift to drag of the airfoil with high lift coefficients. For a given serrated Gurney flap, there was an optimum deflection, At which, the lift-drag ratio of the airfoil can increased not only at high lift coefficient but also at the low to middle angle of attack. It was also found that near-stream wise vortices shed from the serrated edges can make the flow attach to the upper surface near the trailing edge and can delay flow separation.