Dynamic Stall Control via Airfoil Thickness Variation

In this work, a series of numerical experiments are conducted to investigate the effects of control routes in the dynamic stall control via active thickness variation, thereby to clarify the dominant control parameters for optimal thickness variation route. To achieve these goals, the effects of possible control parameters on the stall angle and maximum lift coefficients are thoroughly examined. The results indicate that dynamic stall characteristics have a strong dependency on the thickness variation route of down stroke phase as well as on that of upstroke phase. To be specific, the stall angle is more dependent on control route of upstroke phase, whereas maximum normal force is sensitive to that of the down stroke phase. It is also found that dynamic stall characteristics are dominated by the two major parameters, the thickness and thickness variation. However, on the contrary to thickness, the thickness variation rate has negative effects once the separation occurs.