Patent ID: 8251319
Filing Date: 2012-08-28
Classification: B64C,Y02T

Abstract:
1. An airfoil in the form of a wing, provided with a system for controlling the boundary layer of a laminar flow wing having a flap and a flap hinge line, to reduce profile drag during flap deflection, the system comprising: a first blower including a first plurality of holes along the length of the lower surface of the wing to blow air through the first plurality of holes only during positive flap deflection from a lower surface of the wing to trip flow from laminar to turbulent during such positive flap deflection; a suction device to apply a suction force at the lower surface of the wing to preserve laminar flow past the flap hinge line only during negative flap deflection; and a second blower including a second plurality of holes defined along the length of the lower surface of the flap to blow air from a lower surface of the flap to trip flow from laminar to turbulent before the trailing edge of the flap to reduce separation bubble formation during negative flap deflection.