Patent ID: 7878457

Claim:
A flow control device comprising: vortex generators associated with a flow control surface of an aircraft over which fluid is designed to flow in a predetermined direction, each respective vortex generator having a pivot axis that forms an acute angle with respect to the predetermined direction and capable of being positioned in both of an extended state, in which the respective vortex generators function to create a swirling fluid flow, and a retracted state, in which the respective vortex generators are pivoted via the pivot axis so as to lie generally parallel to, and overlying and protruding from the flow control surface; and an actuator associated with each of the respective vortex generators, each actuator adapted to position the associated vortex generator reversibly between the extended and retracted states, wherein each of the respective vortex generators comprises a shape memory material, and wherein the actuator includes a heater configured to actuate the shape memory material from the retracted state to the extended state, wherein the vortex generators are spaced from a leading edge of the flow control surface.