CHANNELIZED STRATIFIED REGENERATOR WITH INTEGRATED HEAT EXCHANGERS SYSTEM AND METHOD

• US 20060179835A1
• Filed: 02/11/2005
• Published: 08/17/2006
• Est. Priority Date: 02/11/2005
• Status: Active Grant

• Current Assignee: Qnergy Inc.
• Original Assignee: Sterling Technologies LLC
• Inventors: Qiu, Songgang, Augenblick, John E.
• Granted Patent: US 7,137,251 B2
• Time in Patent Office: Days
• US Class Current: 60/521
• CPC Class Codes: F02G 1/057 Regenerators
• CPC Class Codes: F28D 17/02 using rigid bodies, e.g. of porous material

Abstract

A channelized stratified regenerator with integrated heat exchangers are disclosed using micromachining to precisely construct structural geometries, such as fins and axial stratification of material to be used in a Stirling cycle based system. In operation, a working fluid passes through the regenerator when traveling between two heat exchangers. In some implementations, the regenerator and the heat exchangers are formed as a single construction. In other implementations, the regenerator and heat exchangers are formed separately, but are constructed to integrate efficiently with one another.

Claims

1. A Stirling cycle based system for use with a heat source and a heat sink, the system comprising:

a housing shaped to at least partially enclose an internal space from an external space, the internal space having a central longitudinal axis, the external space containing the heat source and the heat sink;

a first heat exchanger no more than a first heat exchanger length along the central longitudinal axis, the first heat exchanger having a plurality of fins, each fin having a first end and a second end, the first end positioned closer to the central axis than the second end, the second end of each fin being thermally coupled to the housing, the fins spaced apart to form a plurality of channels therebetween, each channel of the plurality extending along the central axis for a majority of the first heat exchanger length, each channel configured to carry working fluid to transfer heat to the working fluid from the heat source through the housing;

a second heat exchanger extending no more than a second heat exchanger length along the central longitudinal axis, the second heat exchanger having a plurality of fins, each fin having a first end and a second end, the first end positioned closer to the central axis than the second end, the second end of each fin being thermally coupled to the housing, the fins spaced apart to form a plurality of channels therebetween, each channel of the plurality extending along the central axis for a majority of the second heat exchanger length, each channel configured to carry working fluid to transfer heat from the working fluid to the heat sink through the housing; and

a regenerator extending no more than a regenerator length along the central longitudinal axis, the regenerator having a plurality of fins spaced apart to form a plurality of channels therebetween, each channel of the plurality longitudinally extending along the central axis for a majority of the regenerator length, the regenerator positioned between the first heat exchanger and the second heat exchanger along the central axis to couple the channels of first heat exchanger with the channels of the regenerator and to couple the channels of the regenerator with the channels of the second heat exchanger.

8. The Stirling cycle based system of claim 1 wherein each fin of the second heat exchanger is shaped to at least partially twist around the central longitudinal axis.

9. The Stirling cycle based system of claim 1 wherein the channels of the regenerator are concentrically spaced from one another.

10. The Stirling cycle based system of claim 1 wherein the channels of the regenerator extend radially from the central longitudinal axis.

11. The Stirling cycle based system of claim 1 wherein the channels of the regenerator at least partially twist around the central longitudinal axis.

2. (canceled)

3. A Stirling cycle based system for use with a heat source and a heat sink, the system comprising:

a housing shaped to at least partially enclose an internal space from an external space, the internal space having a central axis, the external space containing the heat source and the heat sink;

a first heat exchanger having a plurality of fins, each fin having a first end and a second end, the first end positioned closer to the central axis than the second end, the second end of each fin being thermally coupled to the housing, the fins spaced apart to form channels, each channel configured to carry working fluid to transfer heat to the working fluid from the heat source through the housing;

a second heat exchanger having a plurality of fins, each fin having a first end and a second end, the first end positioned closer to the central axis than the second end and shaped to at least partially twist around the central axis, the second end of each fin being thermally coupled to the housing, the fins spaced apart to form channels, each channel configured to carry working fluid to transfer heat from the working fluid to the heat sink through the housing;

a regenerator having a plurality of fins spaced apart to from channels, the regenerator positioned between the first heat exchanger and the second heat exchanger along the central axis to couple the channels of first heat exchanger with the channels of the regenerator and to couple the channels of the regenerator with the channels of the second heat exchanger; and

a plurality of diffusers, at least one of the diffusers positioned between the first heat exchanger and the regenerator and having passageways positioned on the diffuser to direct flow of working fluid between the channels of the first heat exchanger and the channels of the regenerator and at least one of the diffusers positioned between the regenerator and the second heat exchanger and having passageways positioned on the diffuser to direct flow of working fluid between the channels of the regenerator and the channels of the second heat exchanger.

4. A Stirling cycle based system comprising:

a housing shaped to at least partially enclose an internal space from an external space;

a heat exchanger positioned in the internal space, the heat exchanger having fins, each fin being thermally coupled to the housing, the fins spaced apart to form channels, each channel configured to carry working fluid, the heat exchanger having a thermal conductivity;

a regenerator having a plurality of fins spaced apart to form channels, the regenerator having a thermal conductivity; and

an insulation component having a thermal conductivity smaller than the thermal conductivity of the heat exchanger and smaller than the thermal conductivity of the regenerator, the insulation component positioned between the heat exchanger and the regenerator, the insulation component having openings in alignment with the channels of the heat exchanger and the channels of the regenerator to allow for flow of working fluid between the heat exchanger and the regenerator.

5. For a Stirling cycle based system having a housing, a first heat exchanger to transfer heat from a heat source external to the housing to a working fluid internal to the housing, a second heat exchanger to transfer heat from the working fluid to a heat sink external to the housing, and a regenerator positioned to contact a portion of the working fluid as the working fluid moves between the first heat exchanger and the second heat exchanger, the method comprising:

forming the housing, the first heat exchanger, the second heat exchanger, and the regenerator from a plurality of material layers by micromachining to define the housing, the first heat exchanger, the second heat exchanger, and the regenerator by In part defining shape, size, and positioning of passages for the first heat exchanger, the second heat exchanger, and the regenerator to direct flow of working fluid through the passages.

6. The method of claim 5 wherein forming produces fins that define the passages.

7. The method of claim 5 wherein forming produces the housing, the first heat exchanger, the second heat exchanger, and the regenerator as a single structural unit.

12. A Stirling cycle based system for use with a heat source and a heat sink, the system comprising:

a heat exchanger having a length along a central axis and having a plurality of heat exchanger channels running along a majority of the length, each heat exchanger channel sized and positioned to carry working fluid containing heat received from the heat source;

a regenerator having a length along the central axis and having a plurality of regenerator channels running along a majority of the length, each regenerator channel sized and positioned to carry working fluid; and

a diffuser positioned between the heat exchanger and the regenerator, the diffuser having passageways positioned on the diffuser to direct flow of working fluid between the channels of the heat exchanger and the channels of the regenerator.

13. The system of claim 12 wherein the plurality of heat exchanger channels have a different width than the plurality of regenerator channels.

14. The system of claim 12 wherein the plurality of heat exchanger channels are of a different number than the plurality of regenerator channels.

15. The system of claim 12 wherein each of the plurality of heat exchanger channels has a different pitch than each of the plurality of regenerator channels.

16. The system of claim 12 wherein the diffuser has a lower thermal conductivity than the regenerator and has a lower thermal conductivity than the heat exchanger.

17. A Stirling cycle based system for use with a heat source and a heat sink, the system comprising:

a heat exchanger having a length along a central axis and having a plurality of heat exchanger channels running along a majority of the length, each channel sized and positioned to carry working fluid containing heat received from the heat source;

a regenerator having a length along the central axis and a plurality of channels running along a majority of the length, each channel sized and positioned to carry working fluid; and

means for diffusing to direct flow of working fluid between the channels of the heat exchanger and the channels of the regenerator.

18. A Stirling cycle based system for use with a heat source and a heat sink, the system comprising;

a heat exchanger having a length along a central axis and having a plurality of heat exchanger channels running along a majority of the length, each heat exchanger channel sized and positioned to carry working fluid containing heat received from the heat source; and

a regenerator having a length along the central axis and a plurality of regenerator channels running along a majority of the length, each regenerator channel sized and positioned to carry working fluid, at least one of the regenerator and the heat exchanger having channels with funneled ends toward the other of the heat exchanger and the regenerator.