Wind turbine having airfoils for blocking and directing wind and rotors with or without a central gap

• US 20040219019A1
• Filed: 04/23/2004
• Published: 11/04/2004
• Est. Priority Date: 04/30/2003
• Status: Active Grant

• Current Assignee: Terra MOYA Aqua Incorporated
• Original Assignee: Ronald J. Taylor, Scott J. Taylor
• Inventors: Taylor, Scott J., Taylor, Ronald J.
• Granted Patent: US 6,966,747 B2
• Time in Patent Office: Days
• US Class Current: 416/132B
• CPC Class Codes: F03D 13/20 Arrangements for mounting or supporting wind motors; Masts or towers for wind motors
• CPC Class Codes: F03D 3/0409 surrounding the rotor F03D3/0427 takes precedence
• CPC Class Codes: F03D 3/0427 with converging inlets, i.e. the guiding means intercepting an area greater than the effective rotor area F03D3/0463, F03D3/049 take precedence
• CPC Class Codes: F05B 2240/213 of the Savonius type
• CPC Class Codes: Y02E 10/728 Onshore wind turbines
• CPC Class Codes: Y02E 10/74 Wind turbines with rotation axis perpendicular to the wind direction
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product
• CPC Class Codes: Y10S 415/908 Axial flow runner
• CPC Class Codes: Y10S 416/04 Fluid current motor and generator
• CPC Class Codes: Y10S 416/09 Savonius

Abstract

A wind turbine device of increased efficiency is comprised of a set of fixed airfoils that direct wind into a rotor having a plurality of blades. The fixed airfoils may extend to the ground to increase the amount of wind directed into the rotor and may be manufactured from concrete. The rotor blades have a vented portion near the axis of rotation that has been found to increase efficiency for certain blade geometries. For other blade geometries, increased efficiency is observed with no gap at the axis of rotation. The rotor may also be manufactured from composite materials to increase strength while decreasing the moment of inertia for the rotor.

Claims

1. A crossflow wind turbine that generates mechanical energy from wind comprising:

a rotor having a plurality of rotor blades that are symmetrically disposed around an axis, said rotor blades disposed in said rotor so that a gap is formed between leading edges of said rotor blades;

a rotor space formed in a volume that is swept out by said rotor blades, said rotor space having a drive portion in which said rotors are driven by said wind and a return portion in which said rotors return to said drive portion;

a plurality of airfoils that direct wind into said drive portion and direct wind away from said return portion to cause said rotor to turn and generate said mechanical energy.

2. The crossflow turbine of claim 1 wherein said rotor blades are disposed in said rotor so that said leading edges are spaced apart from and overlap said axis of said rotor to form said gap.

3. The crossflow turbine of claim 1 wherein said rotor blades are disposed in said rotor so that said leading edges are spaced apart from and are substantially even with said axis to form said gap.

4. The crossflow turbine of claim 2 wherein said rotor blades are disposed in said rotor so that said wind flows across said rotor blades in said drive portion, through said gap, and into said return portion of said rotor space.

5. The crossflow turbine of claim 3 wherein said rotor blades are disposed in said rotor so that said wind flows across said rotor blades in said drive portion, through said gap, and into said return portion of said rotor space.

6. The crossflow turbine of claim 1 wherein said axis is vertical and said airfoils extend at least partially over a base so that said base and said airfoils capture wind along lower portions of said crossflow turbine and direct winds from said lower portion of said crossflow turbine.

7. The crossflow turbine of claim 1 wherein said airfoils are placed symmetrically around said rotor to provide an omnidirectional crossflow turbine.

8. The crossflow turbine of claim 1 wherein said airfoils are placed non-symmetrically around said rotor to provide a substantially bidirectional crossflow turbine.

9. A method of generating mechanical energy from wind comprising:

providing a crossflow wind turbine having airfoils and a rotor that sweeps out a rotor space, said rotor space having a drive portion and a return portion;

symmetrically placing a plurality of rotor blades in said rotor that form a gap between leading edges of said rotor blades;

placing said airfoils around said rotor to substantially direct said wind into said drive portion of said rotor space so that said wind drives said rotor blades in said drive portion, and to substantially block said wind from entering said return portion of said rotor space so that said rotor blades return to said drive portion to generate said mechanical energy.

10. The method of claim 9 wherein said step of symmetrically placing a plurality of rotor blades in said rotor further comprises:

placing said plurality of rotor blades in said rotor so that said leading edges are spaced apart from and overlap an axis of rotation of said rotor to form said gap.

11. The method of claim 9 wherein said step of symmetrically placing a plurality of rotor blades in said rotor further comprises:

placing said plurality of rotor blades in said rotor so that said leading edges are spaced apart from and are substantially even with an axis of rotation of said rotor to form said gap.

12. The method of claim 9 wherein said step of placing said airfoils around said rotor further comprises:

placing at least one airfoil in a position to block said wind from entering said second portion whenever said wind flows substantially from at least one predetermined direction, and placing at least one other airfoil in a position to direct said wind into said first portion whenever said wind is flowing substantially from said at least one predetermined direction.

13. The method of claim 9 wherein:

providing a crossflow turbine comprises providing a vertical crossflow turbine; and

,

placing said airfoils comprises placing said airfoils so that said airfoils at least partially extend over a base to form an airfoil so that said utility enclosure and said airfoils direct wind from lower portions of said crossflow turbine into said crossflow turbine.

14. The method of claim 9 wherein placing said airfoils around said rotors further comprises placing said airfoils symmetrically around said rotor to provide an omnidirectional crossflow turbine.

15. The method of claim 9 wherein placing said airfoils around said rotors further comprises placing said airfoils non-symmetrically around said rotor to provide a substantially bidirectional crossflow turbine.

16. The crossflow turbine of claim 9 wherein symmetrically placing said plurality of rotor blades in said rotor that form a gap comprises symmetrically placing said plurality of rotor blades in said rotor to form a gap so that said wind flows across said rotor blades in said drive portion, through said gap, and into said return portion of said rotor space.

17. A crossflow wind turbine that generates mechanical energy from wind comprising:

a rotor having a plurality of rotor blades that are symmetrically disposed around an axis, said rotor blades disposed in said rotor so that a gap is not formed between leading edges of said rotor blades;

a rotor space formed in a volume that is swept out by said rotor blades, said rotor space having a drive portion in which said rotors are driven by said wind and a return portion in which said rotors return to said drive portion;

a plurality of airfoils that direct wind into said drive portion and direct wind away from said return portion to cause said rotor to turn and generate said mechanical energy.

18. The crossflow turbine of claim 17 wherein said axis is vertical and said airfoils extend at least partially over a base so that said base and said airfoils capture wind along lower portions of said crossflow turbine and direct winds from said lower portion of said crossflow turbine.

19. The crossflow turbine of claim 17 wherein said airfoils are placed non-symmetrically around said rotor to provide a substantially bidirectional crossflow turbine.

20. The crossflow turbine of claim 17 wherein said airfoils are placed non-symmetrically around said rotor to provide a substantially bidirectional crossflow turbine.

21. A method of generating mechanical energy from wind comprising:

providing a crossflow wind turbine having airfoils and a rotor that sweeps out a rotor space, said rotor space having a drive portion and a return portion;

symmetrically placing a plurality of rotor blades in said rotor that do not form a gap between leading edges of said rotor blades;

placing said airfoils around said rotor to substantially direct said wind into said drive portion of said rotor space so that said wind drives said rotor blades in said drive portion, and to substantially block said wind from entering said return portion of said rotor space so that said rotor blades return to said drive portion to generate said mechanical energy.

22. The method of claim 21 wherein:

providing a crossflow turbine comprises providing a vertical crossflow turbine; and

,

placing said airfoils comprises placing said airfoils so that said airfoils at least partially extend over a base to form a ground airfoil so that said utility enclosure and said airfoils direct wind from lower portions of said crossflow turbine into said crossflow turbine.

23. The method of claim 21 wherein placing said airfoils around said rotors further comprises placing said airfoils symmetrically around said rotor to provide a substantially omnidirectional crossflow turbine.

24. The method of claim 21 wherein placing said airfoils around said rotors further comprises placing said airfoils non-symmetrically around said rotor to provide a substantially bidirectional crossflow turbine.