Airfoil with augmented lift
An airfoil having a leading-edge and a trailing edge as well as a suction side and a pressure side is provided. The suction side including an injector slot towards the leading-edge. There may be at least one additional slot towards the trailing edge. The airfoil may be configured for an aircraft. A method of operating an aircraft using such airfoil is also provided.
1 . An airfoil configured for an aircraft, comprising:
a leading edge;
a trailing edge;
a suction side having an injector slot towards the leading edge;
at least one additional slot towards the trailing edge;
a pressure side;
a leading edge part with a leading edge chord line;
a trailing edge part with a trailing chord line;
an injector flap configured to operate on the suction side and to open, close, and/or regulate the opening of the injector slot; and
a plurality of internal structures arranged in a span direction of the airfoil for supporting the injector flap, said internal structures having multiple airflow openings for ensuring airflow in the airfoil;
wherein the leading edge part and the trailing edge part together form the airfoil depending on their relative position,
wherein the injector flap is hinged by a hinge arrangement towards a trailing edge of the injector flap,
wherein the leading edge part and the trailing edge part are configured and arranged relative to each other so as to form the at least one additional slot with an opening in the leading edge body of the airfoil, and
wherein the trailing edge part is configured to open, close and/or regulate the opening of the at least one additional slot, by rotating such that the trailing edge is moved towards the pressure side, wherein the additional slot opening in the leading edge body opens for supplying additional airflow from the leading edge part to the trailing edge of the airfoil.
2 . The airfoil according to claim 1 , wherein the additional slot is disposed along the suction side of the airfoil between the leading edge part and the trailing edge part and wherein the additional slot is opened and closed by dividing the airfoil at the intended slot position and hinging the trailing edge part towards the airfoil on the pressure side, such that the additional slot on the suction side is exposed when the trailing edge part is moved downwards towards the pressure side.
3 . The airfoil according to claim 1 , further comprising at least one additional flap configured to operate to open, close, or regulate the opening of the at least one additional slot.
4 . The airfoil according to claim 1 , wherein the injector slot and at least one additional slot is in communication with flow generating means feeding a flow to the respective injection slot and at least one additional slot.
5 . The airfoil according to claim 1 , wherein the injector slot is configured with injector slot flow generating means feeding an injector flow at an injector flow speed, and wherein the at least one additional slot is configured with additional slot flow generating means feeding an additional flow at an additional flow speed different or independent of the injector flow speed.
6 . A method of operating an aircraft the method comprising:
providing an airfoil having a leading edge, a trailing edge, a suction side having an injector slot towards the leading edge, at least one additional slot towards the trailing edge, the at least one additional slot having an opening in the leading edge body of the airfoil, a pressure side, a leading edge part, a trailing edge part, a plurality of internal structures arranged in a span direction of the airfoil for supporting the injector flap, said internal structures having multiple airflow openings for ensuring airflow in the airfoil, and an injector flap configured to operate on the suction side and to open, close, and/or regulate the opening of the injector slot, wherein the leading edge part and the trailing edge part together form the airfoil depending on their relative position, wherein the injector flap is hinged by a hinge arrangement towards a trailing edge of the injector flap, wherein the leading edge part and the trailing edge part are configured and arranged relative to each other so as to form the at least one additional slot, wherein the trailing edge part is configured to open, close, and/or regulate the opening of the at least one additional slot, by rotating such that the trailing edge is moved towards the pressure side, wherein the additional slot opening in the leading edge body opens to supply additional airflow from the leading edge part to the trailing edge of the airfoil; and
generating slot flow to the respective injector slot and at least one additional slot.
7 . The method of claim 6 , further comprising:
obtaining free air flow around the airfoil;
adjusting angle of attack of the airfoil; and
maintaining a substantially laminar suction side flow from the injector slot and towards the trailing edge.
8 . The method of claim 6 , further comprising:
closing the injector slot and the at least one additional slot; and
operating the aircraft in flight with the chord lines of the trailing edge part and of the leading-edge part aligned.
9 . A flight computer configured to perform the acts of claim 6 .
10 . An aircraft configured with at least one airfoil according to claim 1 and a flight computer.