COMPLIANT WALLED COMBUSTION DEVICES FOR PRODUCING MECHANICAL AND ELECTRICAL ENERGY

• US 20080093849A1
• Filed: 06/14/2007
• Published: 04/24/2008
• Est. Priority Date: 05/26/2004
• Status: Active Grant

• Current Assignee: SRI International, Inc.
• Original Assignee: SRI International, Inc.
• Inventors: Prahlad, Harsha, Stanford, Scott, Heim, Jonathan, Oh, Seajin, Pelrine, Ronald, Kornbluh, Roy
• Granted Patent: US 7,485,978 B2
• Time in Patent Office: Days
• US Class Current: 290/1.00A
• CPC Class Codes: F02B 75/36 Engines with parts of combustion- or working-chamber walls resiliently yielding under pressure

Abstract

Combustion devices described herein comprise a compliant combustion chamber wall or segment. The compliant segment deforms during combustion in the combustion chamber. Some devices may include a compliant wall configured to stretch responsive to pressure generated by combustion of a fuel in the combustion chamber. A coupling portion translates deformation of the compliant segment or wall into mechanical output. One or more ports are configured to inlet an oxygen source and fuel into the combustion chamber and to outlet exhaust gases from the combustion chamber.

Claims

1. A method for producing mechanical energy and electrical energy from a fuel, the method comprising:

providing a fuel and an oxygen source into a combustion chamber;

combusting the fuel in the combustion chamber;

stretching a compliant segment of a wall using pressure generated in the combustion;

translating mechanical energy produced in the combustion to a mechanical output that does work; and

generating electrical energy using mechanical energy produced in the combustion.

2. The method of claim 1 further comprising applying an electric field to a generator that is configured to generate the electrical energy using mechanical energy produced in the combustion.

3. The method of claim 2 wherein the electrical field is applied before the compliant portion contracts from a stretched position.

4. The method of claim 3 wherein the electrical field slows contraction of the compliant segment from the stretched position.

5. The method of claim 2 wherein the generator is also configured to operate as an actuator.

6. The method of claim 5 further comprising applying the electrical field to the actuator before combustion is complete and the electric field increases the mechanical output.

7. The method of claim 2 further comprising applying the electrical field to the actuator at top dead center of the combustion to oppose contraction forces produced in the stretch.

8. The method of claim 2 further comprising sensing position of the stretching compliant segment using the generator.

9. The method of claim 2 wherein the generator attaches to the compliant segment.

10. The method of claim 1 further comprising constraining an outer portion of the compliant segment.

11. The method of claim 1 further comprising igniting the fuel using electrical energy produced by the generator.

12. A combustion cycle for producing mechanical energy and electrical energy from a fuel, the cycle comprising:

providing a fuel and an oxygen source into a combustion chamber;

combusting the fuel in the combustion chamber;

stretching a compliant segment of a wall using pressure generated in the combustion;

translating mechanical energy produced in the combustion to a mechanical output that does work; and

generating electrical energy using elastic return of the stretched compliant segment.

13. The combustion cycle of claim 12 further comprising at least partially exhausting combustion products using elastic return of the stretched compliant segment.

14. The combustion cycle of claim 12 further comprising applying an electric field to a generator that is configured to generate the electrical energy using mechanical energy produced in the combustion.

15. The combustion cycle of claim 14 wherein the electrical field is applied before the compliant portion contracts from a stretched position.

16. The combustion cycle of claim 15 wherein the electrical field slows contraction of the compliant segment from the stretched position.

17. The combustion cycle of claim 12 wherein the generator is also configured to operate as an actuator and the electric field increases the mechanical output.

18. The combustion cycle of claim 17 further comprising applying the electrical field to the actuator before combustion is complete.

19. The combustion cycle of claim 14 further comprising applying the electrical field to the actuator at top dead center of the combustion to oppose contraction forces produced in the stretch.

20. The combustion cycle of claim 12 further comprising igniting the fuel using a portion of the electrical energy.