Application of elastomeric vortex generators

• US 20110008174A1
• Filed: 07/08/2010
• Published: 01/13/2011
• Est. Priority Date: 07/10/2009
• Status: Active Grant

• Current Assignee: Peter Ireland
• Original Assignee: Peter Ireland
• Inventors: Ireland, Peter
• Granted Patent: US 8,870,124 B2
• Time in Patent Office: Days
• US Class Current: 416/223.R
• CPC Class Codes: B64C 2003/147 comprising trailing edges of particular shape
• CPC Class Codes: B64C 23/06 by generating vortices
• CPC Class Codes: B64C 23/065 at the wing tips
• CPC Class Codes: Y02T 50/10 Drag reduction

Abstract

A method of improving aerodynamic performance of foils by the application of conformal, elastomeric vortex generators. The novel use of elastomers allows the application of various forms of vortex generators to sections that have been problematic from engineering and cost considerations. A novel and efficient vortex generator profile is identified, which develops an additional co rotating vortex at low energy expenditure. The mechanisms allow for the application of transverse vortex generators, or Gurney Flaps/Lift Enhancement Tabs/Divergent Trailing Edges, to propellers, rotorblades, and to wings/flaps/control trailing edges. Cove Tabs are additionally described using an elastomeric transverse vortex generator to achieve performance improvements of a high lift device.

Claims

1. An application of elastomeric vortex generators for improving flow on a foil or series of foils, thereby improving lift, drag, angle of attack capability or lift to drag ratios, comprising:

means for providing an element for forming vortices, and a base surface for attachment to a foil or aero/ hydrodynamic surface.

2. The application of elastomeric vortex generators in accordance with claim 1, wherein said means for providing an element for forming vortices, and a base surface for attachment to a foil or aero/hydrodynamic surface comprises a bondable, conformal elastomeric extrusion or section.

3. An application of elastomeric vortex generators for improving flow on a foil or series of foils, thereby improving lift, drag, angle of attack capability or lift to drag ratios, comprising:

a bondable, conformal elastomeric extrusion or section, for providing an element for forming vortices, and a base surface for attachment to a foil or aero/hydrodynamic surface.

4. The application of elastomeric vortex generators as recited in claim 3, further comprising:

a profile in a u form, or alternatively an f profile, or alternatively an inverted t profile, or alternatively an l profile blade section, bondable, conformable, fabricated from an extrusion, mounted at an angle to the freestream flow of between 15 and 25 degrees, location on the surface of the section within 20% of the chord of the wing, flap or surface applied thereon elastomeric blade vortex generator, for developing vortices to re-energise the boundary layer, or to adjust existing flow to improve lift, drag or lift/drag ratios.

5. The application of elastomeric vortex generators as recited in claim 3, further comprising:

an aligned transversely to freestream, parallel to trailing edge, positioned on the lower (high pressure) surface, between 2 and zero time the height of the tab forward of the trailing edge of the wing, or flap, or flap cove, of a height of less than 2% of chord, bondable, conformable, extrusion section of a box, rectangle, or ramp elastomeric gurney tab, for generating an off body recirculation field that then jets the upper flow from the main wing down the face of the flap, reattaching flow on the flap and increasing total lift and reducing drag.

6. The application of elastomeric vortex generators as recited in claim 3, further comprising:

a conformal, bondable u form double blade, for efficiently developing vortices.

7. The application of elastomeric vortex generators as recited in claim 3, further comprising:

a conformal, bondable f form vortex generator, for efficiently developing vortices.

8. The application of elastomeric vortex generators as recited in claim 3, further comprising:

an apex aft facing, v or ogival planform, sub boundary level height, conformal, fabricated from an extruded elastomer section, positioned within 25% of the forward chord of a foil, or section elastomeric ramp form vortex generator, for generating counter rotating streamwise vortices, or as mirror half planform for developing a single vortice, subsequently partitioned to said elastomeric extrusion or section.

9. The application of elastomeric vortex generators as recited in claim 3, further comprising:

a low profile wedge or ogival section, or f, t or u section extrusion, bondable, elastomeric, aligned with aft face at, or forward by not more than 2 times the tab height from the lower trailing edge of the foil section, acts as low tab height lift enhancement tab at low velocities elastomeric divergent trailing edge-lift tab, for developing a transverse vortex proximate to the trailing edge which induces an increase in the wake exit angle and local velocity at the upper trailing edge, resulting in increased aft aerodynamic loading and a reduction in leading edge suction, thereby reducing upper surface velocities while maintaining total lift, and therefore reducing drag and increasing the critical mach number of the foil.

10. The application of elastomeric vortex generators as recited in claim 4, further comprising:

an aligned transversely to freestream, parallel to trailing edge, positioned on the lower (high pressure) surface, between 2 and zero time the height of the tab forward of the trailing edge of the wing, or flap, or flap cove, of a height of less than 2% of chord, bondable, conformable, extrusion section of a box, rectangle, or ramp elastomeric gurney tab, for generating an off body recirculation field that then jets the upper flow from the main wing down the face of the flap, reattaching flow on the flap and increasing total lift and reducing drag.

11. The application of elastomeric vortex generators as recited in claim 4, further comprising:

a low profile wedge or ogival section, or f, t or u section extrusion, bondable, elastomeric, aligned with aft face at, or forward by not more than 2 times the tab height from the lower trailing edge of the foil section, acts as low tab height lift enhancement tab at low velocities elastomeric divergent trailing edge-lift tab, for developing a transverse vortex proximate to the trailing edge which induces an increase in the wake exit angle and local velocity at the upper trailing edge, resulting in increased aft aerodynamic loading and a reduction in leading edge suction, thereby reducing upper surface velocities while maintaining total lift, and therefore reducing drag and increasing the critical mach number of the foil.

12. The application of elastomeric vortex generators as recited in claim 5, further comprising:

a low profile wedge or ogival section, or f, t or u section extrusion, bondable, elastomeric, aligned with aft face at, or forward by not more than 2 times the tab height from the lower trailing edge of the foil section, acts as low tab height lift enhancement tab at low velocities elastomeric divergent trailing edge-lift tab, for developing a transverse vortex proximate to the trailing edge which induces an increase in the wake exit angle and local velocity at the upper trailing edge, resulting in increased aft aerodynamic loading and a reduction in leading edge suction, thereby reducing upper surface velocities while maintaining total lift, and therefore reducing drag and increasing the critical mach number of the foil.

13. The application of elastomeric vortex generators as recited in claim 6, further comprising:

a low profile wedge or ogival section, or f, t or u section extrusion, bondable, elastomeric, aligned with aft face at, or forward by not more than 2 times the tab height from the lower trailing edge of the foil section, acts as low tab height lift enhancement tab at low velocities elastomeric divergent trailing edge-lift tab, for developing a transverse vortex proximate to the trailing edge which induces an increase in the wake exit angle and local velocity at the upper trailing edge, resulting in increased aft aerodynamic loading and a reduction in leading edge suction, thereby reducing upper surface velocities while maintaining total lift, and therefore reducing drag and increasing the critical mach number of the foil.

14. The application of elastomeric vortex generators as recited in claim 7, further comprising:

a low profile wedge or ogival section, or f, t or u section extrusion, bondable, elastomeric, aligned with aft face at, or forward by not more than 2 times the tab height from the lower trailing edge of the foil section, acts as low tab height lift enhancement tab at low velocities elastomeric divergent trailing edge-lift tab, for developing a transverse vortex proximate to the trailing edge which induces an increase in the wake exit angle and local velocity at the upper trailing edge, resulting in increased aft aerodynamic loading and a reduction in leading edge suction, thereby reducing upper surface velocities while maintaining total lift, and therefore reducing drag and increasing the critical mach number of the foil.

15. The application of elastomeric vortex generators as recited in claim 8, further comprising:

a low profile wedge or ogival section, or f, t or u section extrusion, bondable, elastomeric, aligned with aft face at, or forward by not more than 2 times the tab height from the lower trailing edge of the foil section, acts as low tab height lift enhancement tab at low velocities elastomeric divergent trailing edge-lift tab, for developing a transverse vortex proximate to the trailing edge which induces an increase in the wake exit angle and local velocity at the upper trailing edge, resulting in increased aft aerodynamic loading and a reduction in leading edge suction, thereby reducing upper surface velocities while maintaining total lift, and therefore reducing drag and increasing the critical mach number of the foil.

16. The application of elastomeric vortex generators as recited in claim 10, further comprising:

a conformal, bondable u form double blade, for efficiently developing vortices.

17. The application of elastomeric vortex generators as recited in claim 10, further comprising:

a conformal, bondable f form vortex generator, for efficiently developing vortices.

18. The application of elastomeric vortex generators as recited in claim 10, further comprising:

a low profile wedge or ogival section, or f, t or u section extrusion, bondable, elastomeric, aligned with aft face at, or forward by not more than 2 times the tab height from the lower trailing edge of the foil section, acts as low tab height lift enhancement tab at low velocities elastomeric divergent trailing edge-lift tab, for developing a transverse vortex proximate to the trailing edge which induces an increase in the wake exit angle and local velocity at the upper trailing edge, resulting in increased aft aerodynamic loading and a reduction in leading edge suction, thereby reducing upper surface velocities while maintaining total lift, and therefore reducing drag and increasing the critical mach number of the foil.

19. An application of elastomeric vortex generators for improving flow on a foil or series of foils, thereby improving lift, drag, angle of attack capability or lift to drag ratios, comprising:

a bondable, conformal elastomeric extrusion or section, for providing an element for forming vortices, and a base surface for attachment to a foil or aero/hydrodynamic surface;

a profile in a u form, or alternatively an f profile, or alternatively an inverted t profile, or alternatively an l profile blade section, bondable, conformable, fabricated from an extrusion, mounted at an angle to the freestream flow of between 15 and 25 degrees, location on the surface of the section within 20% of the chord of the wing, flap or surface applied thereon elastomeric blade vortex generator, for developing vortices to re-energise the boundary layer, or to adjust existing flow to improve lift, drag or lift/drag ratios;

an aligned transversely to freestream, parallel to trailing edge, positioned on the lower (high pressure) surface, between 2 and zero time the height of the tab forward of the trailing edge of the wing, or flap, or flap cove, of a height of less than 2% of chord, bondable, conformable, extrusion section of a box, rectangle, or ramp elastomeric gurney tab, for generating an off body recirculation field that then jets the upper flow from the main wing down the face of the flap, reattaching flow on the flap and increasing total lift and reducing drag;

a conformal, bondable u form double blade, for efficiently developing vortices;

a conformal, bondable f form vortex generator, for efficiently developing vortices;

an apex aft facing, v or ogival planform, sub boundary level height, conformal, fabricated from an extruded elastomer section, positioned within 25% of the forward chord of a foil, or section elastomeric ramp form vortex generator, for generating counter rotating streamwise vortices, or as mirror half planform for developing a single vortice, subsequently partitioned to said elastomeric extrusion or section; and

a low profile wedge or ogival section, or f, t or u section extrusion, bondable, elastomeric, aligned with aft face at, or forward by not more than 2 times the tab height from the lower trailing edge of the foil section, acts as low tab height lift enhancement tab at low velocities elastomeric divergent trailing edge-lift tab, for developing a transverse vortex proximate to the trailing edge which induces an increase in the wake exit angle and local velocity at the upper trailing edge, resulting in increased aft aerodynamic loading and a reduction in leading edge suction, thereby reducing upper surface velocities while maintaining total lift, and therefore reducing drag and increasing the critical mach number of the foil.