Vortical lift control over a highly swept wing

• US 6,138,955 A
• Filed: 12/23/1998
• Issued: 10/31/2000
• Est. Priority Date: 12/23/1998
• Status: Expired due to Fees

• Current Assignee: Board of Supervisors of Louisiana State University Agricultural & Mechanical College (Louisiana State University System)
• Original Assignee: Board of Supervisors of Louisiana State University Agricultural & Mechanical College (Louisiana State University System)
• Inventors: Gutmark, Ephraim J., Guillot, Stephen A.
• Primary Examiner(s): BAREFOOT, GALEN L
• Application Number:
  US09/220,211
• Time in Patent Office: 678 Days
• Field of Search: 244/204, 244/205, 244/198, 244/199, 244/130, 244/207
• US Class Current: 244/204.1
• CPC Class Codes: B64C 2230/04 by actively generating fluid flow
• CPC Class Codes: B64C 23/06 by generating vortices
• CPC Class Codes: B64C 39/10 All-wing aircraft
• CPC Class Codes: Y02T 50/10 Drag reduction

Abstract

Vortical lift over a highly swept wing can be controlled by stabilizing or strengthening the major vortex by a small continuous jet of air, or a pulsating jet, near the core of the vortex. This method relies on the natural inductive action of the vortex swirling flow to entrain the injected air into the core of the vortex. When the additional momentum from the blowing air becomes aligned with the vortex mean flow direction, the vortex is stabilized and vortex breakdown is delayed.

Claims

1. A controller to enhance or stabilize a vortex created by fluid flowing over a swept wing;

said controller comprising a source of pressurized fluid, and at least one aperture in the upper surface of the wing adapted to inject fluid from said source at least partially into the core of the vortex at a selected velocity and in a selected direction;

wherein the position, velocity, and direction of the injected fluid enhance or stabilize the vortex.

2. An aircraft comprising one or more swept wings comprising a controller as recited in claim 1.

3. A controller as recited in claim 1, wherein the fluid is a gas.

4. A controller as recited in claim 1, wherein the fluid is a liquid.

5. A controller as recited in claim 1, wherein the swept wing is characterized by a wing root of chord length C measured from the apex of the swept wing;

wherein the distance of said aperture from the apex, measured in a direction parallel to the wing root, is between about 0.15 C and about 1.0 C; and

wherein the distance of said aperture from the wing root, measured in a direction perpendicular to the wing root, is between about 0.55 S and about 0.80 S;

wherein S is the width of the swept wing measured in a line perpendicular to the wing root and passing through the aperture.

6. A controller as recited in claim 1, wherein the swept wing is characterized by a wing root of chord length C measured from the apex of the swept wing;

wherein the distance of said aperture from the apex, measured in a direction parallel to the wing root, is between about 0.25 C and about 1.0 C; and

wherein the distance of said aperture from the wing root, measured in a direction perpendicular to the wing root, is between about 0.60 S and about 0.75 S;

wherein S is the width of the swept wing measured in a line perpendicular to the wing root and passing through the aperture.

7. A controller as recited in claim 1, wherein the swept wing is characterized by a wing root of chord length C measured from the apex of the swept wing;

wherein the distance of said aperture from the apex, measured in a direction parallel to the wing root, is about 0.30 C; and

wherein the distance of said aperture from the wing root, measured in a direction perpendicular to the wing root, is about 0.66 S;

wherein S is the width of the swept wing measured in a line perpendicular to the wing root and passing through the aperture.

8. A controller as recited in claim 1, wherein the swept wing is characterized by a wing root of chord length C measured from the apex of the swept wing;

wherein the distance of said aperture from the apex, measured in a direction parallel to the wing root, is about 0.80 C; and

wherein the distance of said aperture from the wing root, measured in a direction perpendicular to the wing root, is about 0.66 S;

wherein S is the width of the swept wing measured in a line perpendicular to the wing root and passing through the aperture.

9. A controller as recited in claim 1, wherein said aperture is movable such that the direction of the injected fluid may be selected, that direction being characterized by a selected pitch angle and a selected azimuthal angle.

10. A controller as recited in claim 9, wherein the pitch angle of said aperture is between about 5°

and about 90°

as measured from the surface of the wing.

11. A controller as recited in claim 9, wherein the pitch angle of said aperture is between about 15°

and about 45°

as measured from the surface of the wing.

12. A controller as recited in claim 9, wherein the azimuthal angle of said aperture is between about 100°

and about 245°

as measured from a direction opposite to that of fluid flow.

13. A controller as recited in claim 9, wherein the azimuthal angle of said aperture is between about 135°

and about 180°

as measured from a direction opposite to that of fluid flow.

14. A controller as recited in claim 1, wherein said controller comprises two or more said apertures.

15. A controller as recited in claim 1, wherein said controller is adapted to inject a steady flow of fluid at least partially into the core of the vortex.

16. A controller as recited in claim 1, wherein said controller is adapted to inject a pulsed flow of fluid at least partially into the core of the vortex.

17. A controller as recited in claim 16, wherein said controller is adapted to time the frequency of the pulsations of the fluid flow to a frequency approximately equal or higher than the natural frequency of the destabilization of the vortex.

18. A controller as recited in claim 1, wherein the swept wing has a leading edge, and wherein said aperture is not along the leading edge of the swept wing.

19. A method to enhance or stabilize a vortex created by a fluid flowing over a swept wing;

said method comprising injecting a pressurized fluid through at least one aperture in the upper surface of the wing at least partially into the core of the vortex at a selected velocity and in a selected direction;

wherein the position, velocity, and direction of the injected fluid enhance or stabilize the vortex.

20. A method to enhance or stabilize vortical lift as recited in claim 19, wherein the swept wing is attached to an aircraft.

21. A method to enhance or stabilize vortical lift as recited in claim 19, wherein the fluid is a gas.

22. A method to enhance or stabilize vortical lift as recited in claim 19, wherein the fluid is a liquid.

23. A method to enhance or stabilize vortical lift as recited in claim 19, wherein the swept wing is characterized by a wing root of chord length C measured from the apex of the swept wing;

wherein the distance of said aperture from the apex, measured in a direction parallel to the wing root, is between about 0.15 C and about 1.0 C; and

wherein the distance of said aperture from the wing root, measured in a direction perpendicular to the wing root, is between about 0.55 S and about 0.80 S;

wherein S is the width of the swept wing measured in a line perpendicular to the wing root and passing through the aperture.

24. A method to enhance or stabilize vortical lift as recited in claim 19, wherein the swept wing is characterized by a wing root of chord length C measured from the apex of the swept wing;

wherein the distance of said aperture from the apex, measured in a direction parallel to the wing root, is between about 0.25 C and about 1.0 C; and

wherein the distance of said aperture from the wing root, measured in a direction perpendicular to the wing root, is between about 0.60 S and about 0.75 S;

wherein S is the width of the swept wing measured in a line perpendicular to the wing root and passing through the aperture.

25. A method to enhance or stabilize vortical lift as recited in claim 19, wherein the swept wing is characterized by a wing root of chord length C measured from the apex of the swept wing;

wherein the distance of said aperture from the apex, measured in a direction parallel to the wing root, is about 0.30 C; and

wherein the distance of said aperture from the wing root, measured in a direction perpendicular to the wing root, is about 0.66 S;

wherein S is the width of the swept wing measured in a line perpendicular to the wing root and passing through the aperture.

26. A method to enhance or stabilize vortical lift as recited in claim 19, wherein the swept wing is characterized by a wing root of chord length C measured from the apex of the swept wing;

wherein the distance of said aperture from the apex, measured in a direction parallel to the wing root, is about 0.80 C; and

wherein the distance of said aperture from the wing root, measured in a direction perpendicular to the wing root, is about 0.66 S;

wherein S is the width of the swept wing measured in a line perpendicular to the wing root and passing through the aperture.

27. A method to enhance or stabilize vortical lift as recited in claim 19, wherein the aperture is movable such that the direction of the injected fluid may be selected, the direction being characterized by a selected pitch angle and a selected azimuthal angle.

28. A method to enhance or stabilize vortical lift as recited in claim 27, wherein the pitch angle of said aperture is between about 5°

and about 90°

as measured from the surface of the wing.

29. A method to enhance or stabilize vortical lift as recited in claim 27, wherein the pitch angle of said aperture is between about 15°

and about 45°

as measured from the surface of the wing.

30. A method to enhance or stabilize vortical lift as recited in claim 27, wherein the azimuthal angle of said aperture is between about 100°

and about 245°

as measured from a direction opposite to that of the fluid flow.

31. A method to enhance or stabilize vortical lift as recited in claim 27, wherein the azimuthal angle of said aperture is between about 135°

and about 180°

as measured from a direction opposite to that of the fluid flow.

32. A method to enhance or stabilize vortical lift as recited in claim 19, said method comprising injecting a pressurized fluid through at least two apertures as recited.

33. A method to enhance or stabilize vortical lift as recited in claim 19, wherein said injecting comprises injecting a steady flow of fluid at least partially into the core of the vortex.

34. A method to enhance or stabilize vortical lift as recited in claim 19, wherein said injecting comprises injecting a pulsed flow of fluid at least partially into the core of the vortex.

35. A method to enhance or stabilize vortical lift as recited in claim 34, wherein said injecting comprises injecting pulsed fluid at a frequency approximately equal or higher than the natural frequency of the destabilization of the vortex.

36. A method to enhance or stabilize vortical lift as recited in claim 19, wherein the swept wing has a leading edge, and wherein the aperture is not along the leading edge of the swept wing.