Patent ID: 7537182

Claim:
A method of controlling the shear layer of an airflow, comprising the steps of: providing an airfoil having (i) a main body defining a leading edge with first separation control devices (SCDs) distributed along at least a portion of the leading edge, and (ii) a flap hingedly coupled to the main body at a flap shoulder and defining a trailing edge of the airfoil with second separation control devices (SCDs) distributed along at least a portion of the flap shoulder that is aligned with said portion of the leading edge with respect to the direction of the airflow; deflecting the flap into the airflow; simultaneously introducing periodic disturbances into the airflow moving over the airfoil at both the leading edge and at the flap shoulder using the first SCDs and second SCDs, respectively, wherein said periodic disturbances introduced at the leading edge have substantially the same amplitude all along said portion of the leading edge, said periodic disturbances having a dimensionless frequency F + that satisfies the relationship 0.3≦F + ≦3, said periodic disturbances generating vortices in the airflow wherein the vortices generated at the leading edge interact with the vortices generated at the flap shoulder; and adjusting a phase difference between said periodic disturbances simultaneously introduced into the airflow at both the leading edge and at the flap shoulder to vary lift on the airfoil.