Underwater ducted turbine

• US 7,471,009 B2
• Filed: 09/16/2002
• Issued: 12/30/2008
• Est. Priority Date: 09/17/2001
• Status: Expired due to Fees

• Current Assignee: Clean Current Limited Partnership
• Original Assignee: Clean Current Power Systems Incorporated
• Inventors: Grillos, Emmanuel, Allison, Stephen
• Primary Examiner(s): GONZALEZ, JULIO CESAR
• Application Number:
  US10/489,642
• Publication Number:
  US 20050285407A1
• Time in Patent Office: 2,297 Days
• Field of Search: 290/42,43,54,53,55 415/7 60/496,497
• US Class Current: 290/54
• CPC Class Codes: F03B 13/083 The generator rotor being mounted as turbine rotor rim
• CPC Class Codes: F03B 13/10 Submerged units incorporating electric generators or motors
• CPC Class Codes: F03B 13/264 using the horizontal flow of water resulting from tide movement
• CPC Class Codes: F03B 17/061 with rotation axis substantially in flow direction
• CPC Class Codes: F03B 3/128 Mounting, demounting
• CPC Class Codes: F05B 2210/16 Air or water being indistinctly used as working fluid, i.e. the machine can work equally with air or water without any modification
• CPC Class Codes: F05B 2210/404 bidirectional, i.e. in opposite, alternating directions
• CPC Class Codes: F05B 2220/7066 via a direct connection, i.e. a gearless transmission
• CPC Class Codes: F05B 2220/7068 equipped with permanent magnets
• CPC Class Codes: F05B 2240/133 with a convergent-divergent guiding structure, e.g. a Venturi conduit
• CPC Class Codes: F05B 2240/93 on a structure floating on a liquid surface
• CPC Class Codes: F05B 2240/97 on a submerged structure
• CPC Class Codes: F05B 2260/63 Preventing clogging or obstruction of flow paths by dirt, dust, or foreign particles
• CPC Class Codes: Y02E 10/20 Hydro energy
• CPC Class Codes: Y02E 10/30 Energy from the sea, e.g. using wave energy or salinity gradient

Abstract

An apparatus is disclosed for a turbine for generating electrical power from water or air flow comprising at least one rotor disk having a plurality of hydrofoil blades, a guide vanes, a cylindrical housing, and a generator means. A rim generator comprising a magnet race rotor rim and fixed stator coils in the housing is used. The apparatus is fitted with a screen to stop the ingress of debris and marine life, and a skirt augmenter device to reduce the Betz effect. The apparatus is preferably for sub-sea deployment and driven by tidal currents, but may be powered by river current or wave driven air or by wind. The apparatus may be deployed on at least one telescoping pole, tethered to the sea-bed and kept buoyant by buoyant concrete in the housing, inserted in a dam, under a barge or in a tidal power array.

Claims

1. A hydro turbine generator for generating electrical power from water flow, said apparatus comprising a hub substantially parallel to a water flow and at least one generator and characterized by:

(a) at least one rotor disk comprising a plurality of hydrofoil blades rotatably attached to said hub and extending radially from said hub;

(b) a generally cylindrical housing defining a duct, said duct being proximate to the tips of said blades and attached to said hub by a plurality of curved guide vanes extending radially between said hub and said duct, such that said curved guide vanes are operable to change the direction of said water flow.

2. The apparatus according to claim 1 wherein said blades are symmetric in cross section.

3. The apparatus according to claim 2 wherein said blades have two flat faces which are disposed perpendicular to said water flow.

4. The apparatus according to claim 1 wherein there is a first rotor disk and a second rotor disk, said first rotor disk being upstream and rotating in a first direction to the water flow and said second rotor disk being downstream and counter-rotating in relation to said first rotor disk in a second direction to the water flow.

5. The apparatus according to claim 4 wherein said first direction is counter clockwise from the direction of the water flow, and said second direction is clockwise from said water flow direction.

6. The apparatus according to claim 4 wherein said first direction is clockwise from the direction of water flow, and said second direction is counter-clockwise from said water flow direction.

7. The apparatus according to claim 4 wherein when said water flow changes direction, said second rotor disk becomes the upstream disk, and continues to rotate in the same direction, while said first rotor disk becomes the downstream disk, and continues to counter-rotate in relation to said in the same direction upstream disk.

8. The apparatus according to claim 1 wherein said guide vanes are disposed at one or both ends of said hub.

9. The apparatus according to claim 1 wherein said guide vanes are substantially rectangular and comprise a curve such that said curve changes said water flow direction such that it strikes said hydrofoil blades at an acute angle to create lift and therefore rotation of said rotor disks.

10. The apparatus according to claim 1, wherein said vanes are fixed in place.

11. The apparatus according to claim 1, wherein said vanes are adjustable.

12. The apparatus according to claim 1 wherein said guide vanes are rotatably adjustable relative to said hub and said duct.

13. The apparatus according to claim 7 wherein when said water flow changes direction, said guide vanes rotate such that the curve of said guide vanes are reversed, thereby directing said water flow at a preferred angle.

14. The apparatus according to claim 7 wherein when said water flow changes direction, said curved guide vanes rotate such that said vanes directing said water flow on to said upstream rotor disk are reversed, thereby directing said water flow out of the new downstream rotor disk parallel to the axis of said hub, and said vanes disposed at the downstream end of said hub directing said water flow out of said turbine generator are now reversed to a position for directing said water flow at an acute angle onto said former downstream rotor disk.

15. The apparatus according to claim 12 wherein said vanes are rotated by means of a mechanical coupling to a skirt which flips from one end of said duct to the other as said water flow changes direction.

16. The apparatus according to claim 1 wherein said generator is a rim generator.

17. The apparatus according to claim 1 wherein said generator is comprised of magnets disposed at the tips of said blades and solenoids disposed in the interior wall of said duct.

18. The apparatus according to claim 1 wherein said generator is comprised of permanent magnets in a rim of said rotor disk and stator coils are disposed in the interior wall of said duct.

19. The apparatus according to claim 1 wherein said generator is one of a dual or single axial flux generator or a dual or single radial flux generator.

20. The apparatus according to claim 1 wherein said generator is flooded with ambient water.

21. The apparatus according to claim 1 wherein said rotor disks and generators are adapted to be removed as a modular unit, such that maintenance and replacement is easily facilitated.

22. The apparatus according to claim 1 further comprising a reversible skirt disposed about the midline of the outer surface of said duct and extending past one open end of said duct in the direction of said water flow.

23. The apparatus according to claim 22 wherein said skirt is adapted to lift and flip when said water flow reverses such that said skirt will always extend from said midline of said duct towards the downstream end of said hydro turbine.

24. The apparatus according to claim 22 wherein said skirt is comprised of a flexible material.

25. The apparatus of claim 22 wherein said skirt is comprised of articulated panels.

26. The apparatus according to claim 1 further comprising a screen disposed about the open ends of said duct such that debris and live creatures are deflected by said screen.

27. The apparatus according to claim 26 wherein said screen consists of metal bars.

28. The apparatus according to claim 26 wherein said bars extend forward from said duct ends to a point in front of the center of said duct ends.

29. The apparatus according to claim 26 wherein said screen consists of slats angled tangentially to said water flow such that debris and live creatures are deflected around said turbine.

30. An apparatus according to claim 1 wherein at least one turbine generator is mounted on at least one sub-marine telescoping pylon adapted to selectively lower or raise said turbine generator above a water surface and to selected sub-marine depths such that power generation is optimized.

31. The apparatus according to claim 1 wherein said hydro turbine generator is bi-directional and can accept said water flow from either of two open ends and generate power.

32. The apparatus according to claim 1 wherein said duct has a converging inner surface such that a venturi effect is created.

33. The apparatus according to claim 4 wherein said rotor disks are coaxial and counter-rotating.

34. The apparatus according to claim 33 wherein there are 2 to 10 cascading pairs of coaxial counter-rotating turbine generators.

35. The apparatus according to claim 13 wherein said vanes are rotated by means of a mechanical coupling to a skirt which flips from one end of said duct to the other as said water flow direction changes.

36. The apparatus according to claim 14 wherein said vanes are rotated by means of a mechanical coupling to a skirt which flips from one end of said duct to the other as said water flow direction changes.

37. The apparatus according to claim 23 wherein said skirt is comprised of a flexible material.

38. The apparatus of claim 23 wherein said skirt is comprised of articulated panels.

39. The apparatus according to claim 1 further comprising a bypass hole defined by said hub such that said water flow passes longitudinally through said hub.