Pliant mechanisms for extracting power from moving fluid

• US 7,839,007 B2
• Filed: 09/29/2009
• Issued: 11/23/2010
• Est. Priority Date: 05/01/2007
• Status: Active Grant

• Current Assignee: Pliant Energy Systems LLC
• Original Assignee: Pliant Energy Systems LLC
• Inventors: Filardo, Benjamin Pietro
• Primary Examiner(s): Ponomarenko; Nicholas
• Application Number:
  US12/569,762
• Publication Number:
  US 20100084871A1
• Time in Patent Office: 420 Days
• Field of Search: 290/43, 290/44, 290/53, 290/54, 290/55, 310/330, 310/367
• US Class Current: 290/43
• CPC Class Codes: F03B 17/06 using liquid flow with predominantly kinetic energy conversion, e.g. of swinging-flap type , "run-of-river", "ultra-low head" F03B13/264 takes precedence
• CPC Class Codes: F05B 2240/311 flexible or elastic
• CPC Class Codes: H02N 2/185 using fluid streams
• 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

Flexible and elastic mechanisms for extracting power from a moving fluid. Sheet-like material is deformed during fabrication through an applied force so as to create undulations in said material, whose stresses are maintained through restraining components, thereby maintaining the occurrence of said deformations in the material. When placed in moving fluid, the resulting pressure differentials cause the positions of the undulations within the material to travel along said material in the same direction as the moving fluid. Power is extracted in one of two principle ways. The first is via a mechanical coupling of the sheet-like material to a rotating mechanism, which turns an electro-magnetic dynamo or other output device. The second is via the utilization of a flexible material which exhibits an electrical response to mechanical strain, whereby the strains caused by the travel of undulations along the material create an electrical current which is extracted via two or more electrodes.

Claims

1. A power extraction apparatus for extracting power from a flowing fluid, comprising:

a base member fixed relative to the flowing fluid;

a flexible article connected to the base member that is disposed in contact with the flowing fluid, having at least one contact surface permanently configured with a persistently maintained deformation projecting transverse to a longitudinal axis of the flexible article, the longitudinal axis being oriented substantially parallel to a primary flow direction of the flowing fluid, wherein the at least one persistently maintained deformation is maintained regardless of the flowing fluid and dynamically undulates in response to forces imposed by the flowing fluid; and

an undulating motion power extraction component coupled to undulations of the at least one persistent deformation to extract power therefrom.

2. The apparatus of claim 1, wherein the at least one persistent deformation extends longitudinally along the longitudinal axis of the flexible article.

3. The apparatus of claim 1, further comprising:

at least one deformation retaining component connected to the flexible article, wherein the at least one persistent deformation is maintained by the at least one deformation retaining component.

4. The apparatus of claim 3, wherein the flexible article comprises a ribbon, the deformation retaining component comprises a crenated strip having a straight edge and an undulating edge, and

wherein the ribbon is connected along one edge to the undulating edge of the crenated strip.

5. The apparatus of claim 4, wherein the deformation retaining component further comprises:

a support member connected to the straight edge of the crenated strip, wherein the support member exhibits at least one of rigidity and tensility.

6. The apparatus of claim 4, further comprising a second crenated strip having a second straight edge and a second undulating edge and connected to a second edge of the ribbon along the second undulating edge.

7. The apparatus of claim 1, wherein the flexible article comprises a first tube, and the at least one persistent deformation comprises a first persistent bulge in a cross-section of the first tube.

8. The apparatus of claim 7, further comprising

at least one deformation retaining component connected to the first tube, wherein the first persistent bulge is maintained by the at least one deformation retaining component.

9. The apparatus of claim 7, further comprising a second tube situated substantially concentric with the first tube and having at least one second persistent deformation comprising a second persistent bulge in a cross-section of the second tube.

10. The apparatus of claim 9, wherein the first tube and the second tube are each attached to a support frame.

11. The apparatus of claim 9, wherein undulations of the first persistent bulge in the first tube are substantially in phase with undulations of the second persistent bulge in the second tube.

12. The apparatus of claim 9, wherein undulations of the first persistent bulge in the first tube are substantially out of phase with undulations of the second persistent bulge in the second tube.

13. The apparatus of claim 7, further comprising:

a second tube connected along its side with a side of the first tube and having at least one second persistent deformation comprising a second persistent bulge in a cross-section of the second tube.

14. The apparatus of claim 1, wherein the undulating motion power extraction component is an electrical power extraction component.

15. The apparatus of claim 14, wherein the flexible article comprises electroactive material, and wherein the electrical power extraction component comprises electrodes electrically coupled to the electroactive material to withdraw the electrical power from the undulations of the electroactive material.

16. The apparatus of claim 15, wherein the electrodes extract electrical power associated with strains of the electroactive material caused by excitation of the undulations.

17. The apparatus of claim 16, wherein the electroactive material comprises electroactive polymers.

18. The apparatus of claim 1, wherein the undulating motion power extraction component is a mechanical power extraction component.

19. The apparatus of claim 18, wherein the mechanical power extraction component comprises an electromechanical generator mechanically coupled to the flexible article to convert the mechanical power associated with the undulations to electrical power.

20. The apparatus of claim 18, wherein the mechanical power extraction component comprises a ratcheted axle coupled to undulations of the at least one persistent deformation.

21. The apparatus of claim 18, wherein the mechanical power extraction component is a pump.

22. A system for extracting power from a flowing fluid, comprising:

means for converting motion of the flowing fluid into undulations of at least one persistently maintained deformation of a contact surface of a flexible article disposed in contact with the flowing fluid, wherein the at least one persistently maintained deformation is maintained regardless of the flowing fluid; and

means for extracting power from the undulations of the at least one persistent deformation.

23. A method for extracting power from a flowing fluid, comprising:

forming at least one persistently maintained deformation in a flexible article;

coupling the at least one persistently maintained deformation to at least one undulating motion power extraction component;

disposing the flexible article in a flowing fluid such that the at least persistently maintained deformation has a projection transverse to a primary flow direction of the flowing fluid; and

extracting power from undulations of the at least one persistent deformation caused by the flowing fluid using the at least one undulating motion power extraction component.

24. A method of forming an apparatus for extracting power from a flowing fluid, comprising:

forming a deformation in a flexible article, wherein the deformation is excitable by a flowing fluid in contact with the flexible article to undulate in response to forces imposed by the flowing fluid;

securing the deformation with a first deformation retaining component to create a persistently maintained deformation ; and

coupling an undulating motion power extraction component to the flexible article, wherein the undulating motion power extraction component is configured to extract power from dynamic undulations of the persistently maintained deformation.