GENERATING ENERGY FROM FLUID EXPANSION

• US 20110289922A1
• Filed: 05/28/2010
• Published: 12/01/2011
• Est. Priority Date: 05/28/2010
• Status: Active Grant

• Current Assignee: Clean Energy HRS LLC
• Original Assignee: Calnetix Incorporated (General Electric Company)
• Inventors: Huber, David J., Myers, Scott R.
• Granted Patent: US 8,739,538 B2
• Time in Patent Office: Days
• US Class Current: 60/651
• CPC Class Codes: F01D 1/023 the working-fluid being divided into several separate flows F01D3/02 takes precedence; several separate fluid flows being united in a single flow; the machine or engine having provision for two or more different possible fluid flow paths
• CPC Class Codes: F01D 15/10 Adaptations for driving, or combinations with, electric generators
• CPC Class Codes: F01D 3/02 characterised by having one fluid flow in one axial direction and another fluid flow in the opposite direction
• CPC Class Codes: F01K 25/10 the vapours being cold, e.g. ammonia, carbon dioxide, ether
• CPC Class Codes: F05D 2220/31 in steam turbines
• CPC Class Codes: F05D 2240/51 Magnetic

Abstract

An apparatus includes an electric generator having a stator and a rotor. A first turbine wheel is coupled to a first end of the rotor to rotate at the same speed as the rotor. A second turbine wheel is coupled to a second end of the rotor opposite the first end, and configured to rotate at the same speed as the rotor. The first and second turbine wheels may rotate in response to expansion of a working fluid flowing from an inlet side to an outlet side of the turbine wheels.

Claims

1. An apparatus comprising:

an electric generator having a stator and a rotor;

a first turbine wheel coupled to a first end of the rotor to rotate at the same speed as the rotor and configured to receive working fluid into an inlet side of the first turbine wheel and output working fluid from an outlet side of the first turbine wheel and rotate in response to expansion of working fluid flowing from the inlet side to the outlet side of the first turbine wheel; and

a second turbine wheel coupled to a second end of the rotor, opposite the first end of the rotor, to rotate at the same speed as the rotor and configured to receive working fluid into an inlet side of the second turbine wheel and output working fluid from an outlet side of the second turbine wheel and rotate in response to expansion of working fluid flowing from the inlet side to the outlet side of the second turbine wheel.

2. The apparatus of claim 1 wherein the first turbine wheel is configured to receive working fluid radially into the inlet side of the first turbine wheel and output working fluid axially from the outlet side of the first turbine wheel.

3. The apparatus of claim 2 wherein the second turbine wheel is configured to receive working fluid radially into an inlet side of the second turbine wheel and output working fluid axially from the outlet side of the second turbine wheel.

4. The apparatus of claim 1 wherein the first turbine wheel is configured to direct working fluid from the outlet side of the first turbine wheel through the electric generator.

5. The apparatus of claim 4 wherein the second turbine wheel is configured to direct working fluid from the outlet side of the second turbine wheel through the electric generator.

6. The apparatus of claim 4 wherein the inlet side of the second turbine wheel is proximate the electric generator, and the second turbine wheel is configured to receive the at least part of the working fluid from an outlet of the electric generator to the inlet side of the second turbine wheel.

7. The apparatus of claim 1 wherein the electric generator is arranged proximate the inlet side of the first turbine wheel.

8. The apparatus of claim 7 wherein the electric generator is arranged proximate the inlet side of the second turbine wheel.

9. The apparatus of claim 1 wherein the second turbine wheel is configured to receive working fluid into the inlet side of the second turbine wheel from the outlet side of the first turbine wheel.

10. The apparatus of claim 1 wherein the rotor is directly coupled to the first turbine wheel.

11. The apparatus of claim 1 wherein the rotor and the turbine wheel are coupled to rotate together without a gear box.

12. The apparatus of claim 1 wherein the apparatus further comprises at least one magnetic bearing supporting the rotor relative to the stator.

13. The apparatus of claim 1 wherein the apparatus is configured so that the first turbine wheel receives the same working fluid as the second turbine wheel.

14. A generator system for use in a Rankine cycle, comprising:

a liquid reservoir for a working fluid of the Rankine cycle;

a pump device coupled to the liquid reservoir to receive the working fluid from the liquid reservoir;

an evaporator heat exchanger coupled to the pump device to receive the working fluid from the pump and apply heat to the working fluid;

a turbine generator apparatus coupled to the evaporator heat exchanger to receive the working fluid from the evaporator heat exchanger and configured to generate electrical energy in response to expansion of the working fluid, the turbine generator apparatus comprising;

an electric generator having a stator and a rotor,

a first turbine wheel coupled to a first end of the rotor to rotate at the same speed as the rotor and configured to receive a working fluid into an inlet side of the first turbine wheel and output the working fluid from an outlet side of the first turbine wheel and rotate in response to expansion of the working fluid flowing from the inlet side to the outlet side of the first turbine wheel, and

a second turbine wheel coupled to a second end of the rotor, opposite the first end of the rotor, to rotate at the same speed as the rotor; and

a condenser heat exchanger coupled to the turbine generator apparatus to receive the working fluid from the turbine generator apparatus and extract heat from the working fluid.

15. The system of claim 14 wherein the first turbine wheel is configured to receive the working fluid radially into the inlet side of the first turbine wheel and output the working fluid axially from the outlet side of the first turbine wheel.

16. The apparatus of claim 14 wherein the first turbine wheel is configured to direct at least part of the working fluid from the outlet side of the first turbine wheel through the electric generator.

17. The system of claim 14 wherein the electric generator is arranged proximate the inlet side of the first turbine wheel.

18. The system of claim 14 wherein the rotor is directly coupled to the first turbine wheel.

19. The system of claim 14 wherein the Rankine cycle is an organic Rankine cycle.

20. The system of claim 14 wherein the second turbine wheel is configured to receive the working fluid into an inlet side of the second turbine wheel and output the working fluid from an outlet side of the second turbine wheel and rotate in response to expansion of the working fluid flowing from the inlet side to the outlet side of the second turbine wheel.

21. A method of circulating a working fluid through a working cycle, comprising:

vaporizing the working fluid;

receiving at least a part of the vaporous working fluid into an inlet side of a first turbine wheel and an inlet side of a second turbine wheel;

rotating the first and second turbine wheels in response to expansion of the working fluid through the turbine wheels, and in turn rotating a rotor of a generator at the same speed as the first and second turbine wheels;

outputting the working fluid from an outlet side of the first turbine wheel and an outlet side of the second turbine wheel; and

condensing the working fluid to a liquid.

22. The method of claim 21 wherein receiving the vaporous working fluid into an inlet of the first turbine wheel comprises receiving the vaporous working fluid into a radial inlet of the first turbine wheel and outputting the working fluid from an outlet side of the first turbine wheel comprises outputting the working fluid axially from the outlet side of the first turbine wheel.

23. The method of claim 21 wherein rotating the rotor comprises rotating a shaft common to the first turbine wheel and the rotor.

24. The method of claim 23 wherein the shaft is connected to the second turbine wheel.

25. The method of claim 23 wherein the first and second turbine wheels are affixed directly to the rotor.

26. The method of claim 21 wherein the working cycle is an organic Rankine working cycle.