Optimization design of hybird laminar flow control airfoil using Directly Manipulated Free-form Deformation technique

This paper described a methodology for airfoil optimization with hybrid laminar flow control, and the DFFD (Directly Manipulated Free-form Deformation) technique was used to improve the controllability and decrease the number of design variables. Compared with natural laminar flow, the application of suction over the first 10% ∶ 20% of the chord could delay the transition efficiently. The optimized foils enhanced the aerodynamic performance at design point. Meanwhile, the effects under different suction coefficient and off-design conditions were presented.