Control of Separation Flow on Flap by Moving Surface Method

The moving surface method based on Quette Flow-type momentum addition was proposed as a new flow separation control method in order to suppress the flow separation over a flap at high attack angles and make lift enhancement. The effectiveness of the proposed method as well as the mechanism for suppressing the separation was studied by numerical simulations and experimental measurements in this study. The numerical results show that the moving surface works well to suppress the flap flow separation, so that lift coefficient can be increased significantly. In addition, the moving surface decreases pressure not only in the original separated flow region, but also in the leading edge region. Furthermore, the experimental result agrees with the numerical one in the case of a lower Mach number, which can validate the numerical results. Thus, the moving surface method proposed here is a promising method for controlling the flow separation over the flap.