HEAT TRANSFER SYSTEM

• US 20120131932A1
• Filed: 02/06/2012
• Published: 05/31/2012
• Est. Priority Date: 06/30/2000
• Status: Active Grant

• Current Assignee: Alliant Techsystems Incorporated (Northrop Grumman Corporation)
• Original Assignee: Alliant Techsystems Incorporated (Northrop Grumman Corporation)
• Inventors: Kroliczek, Edward J., Nikitkin, Michael, Wolf, David A. Sr.
• Granted Patent: US 9,631,874 B2
• Time in Patent Office: Days
• US Class Current: 62/6
• CPC Class Codes: F28D 15/043 forming loops, e.g. capillary pumped loops
• CPC Class Codes: Y10T 29/49353 Heat pipe device making

Abstract

A thermodynamic system includes a cyclical heat exchange system and a heat transfer system coupled to the cyclical heat exchange system to cool a portion of the cyclical heat exchange system. The heat transfer system includes an evaporator including a wall configured to be coupled to a portion of the cyclical heat exchange system and a primary wick coupled to the wall and a condenser coupled to the evaporator to form a closed loop that houses a working fluid.

Claims

1. A thermodynamic system, comprising:

a heat transfer system, comprising;

an evaporator, comprising;

a heated wall;

a primary wick coupled to the heated wall;

a liquid barrier wall, wherein the primary wick is positioned between the heated wall and the liquid barrier wall and wherein the heated wall and the liquid barrier wall are configured to contain a working fluid between adjacent sides of the heated wall and the liquid barrier wall;

a vapor removal channel located at an interface between the primary wick and the heated wall, the vapor removal channel extending to a vapor outlet;

a liquid flow channel located between the liquid barrier wall and the primary wick, the liquid flow channel for receiving liquid from a liquid inlet; and

a condenser coupled to the evaporator to form a closed loop that houses a working fluid.

2. The thermodynamic of claim 1, wherein the condenser comprises a vapor inlet and a liquid outlet and the evaporator comprises a liquid inlet and a vapor outlet.

3. The thermodynamic of claim 2, further comprising:

a vapor line providing fluid communication between the vapor outlet of the evaporator and the vapor inlet of the condenser; and

a liquid return line providing fluid communication between the liquid outlet of the condenser and the liquid inlet of the evaporator.

4. The thermodynamic of claim 1, wherein the heat transfer system is configured to move the working fluid through the heat transfer system passively.

5. The thermodynamic of claim 3, further comprising an additional evaporator coupled to the vapor line.

6. The thermodynamic of claim 4, wherein the heat transfer system is configured to move the working fluid through the heat transfer system without the use of an external pump.

7. The thermodynamic of claim 5, wherein the wick is configured to move the working fluid through the heat transfer system.

8. The thermodynamic of claim 3, wherein the heat transfer system is configured to change the working fluid between a liquid and a vapor as the working fluid passes through at least one of the evaporator, the condenser, the vapor line, and the liquid return line.

9. The thermodynamic of claim 1, further comprising fins coupled to the condenser.

10. The thermodynamic of claim 1, wherein the primary wick, the heated wall, and the liquid barrier wall of the evaporator are annular.

11. The thermodynamic of claim 1, further comprising a cryocooler thermally coupled to the condenser.

12. The thermodynamic of claim 1, wherein the primary wick, the heated wall, and the liquid barrier wall of the evaporator are substantially coplanar.

13. The thermodynamic system of claim 1, further comprising:

a cyclical heat exchange system; and

wherein the heat transfer system is thermally coupled by the heated wall to the cyclical heat exchange system to cool a portion of the cyclical heat exchange system.

14. The thermodynamic system of claim 13, wherein the evaporator is integral with the cyclical heat exchange system.

15. The thermodynamic system of claim 13, wherein the cyclical heat exchange system includes a Stirling heat exchange system.

16. The thermodynamic system of claim 13, wherein the cyclical heat exchange system includes a refrigeration system.

17. The thermodynamic system of claim 13, wherein the heat transfer system is coupled to one of a hot side of the cyclical heat exchange system and a cold side of the cyclical heat exchange system.

18. An evaporator for a heat transfer system, the evaporator comprising:

a heated wall;

a liquid barrier wall adjacent the heated wall, the liquid barrier wall and the heated wall being configured to contain working fluid between adjacent sides of the heated wall and the liquid barrier wall;

a primary wick positioned between the adjacent sides of the heated wall and the liquid barrier wall;

a vapor removal channel that is located at an interface between the primary wick and the adjacent side of the heated wall; and

a liquid flow channel located between the adjacent side of the liquid barrier wall and the primary wick.

19. The evaporator of claim 18, wherein the primary wick, the heated wall, and the liquid barrier wall are substantially coplanar.

20. The evaporator of claim 18, wherein the primary wick has a thermal conductivity that is low enough to at least substantially prevent the formation of vapor bubbles in the liquid flow channel caused by leakage of heat from the heated wall, through the primary wick, toward the liquid barrier wall.

21. The evaporator of claim 18, wherein the heated wall is defined so as to accommodate the vapor removal channel.

22. The evaporator of claim 18, wherein the interface between the primary wick and the adjacent side of the heated wall is defined so as to accommodate the vapor removal channel.

23. The evaporator of claim 18, wherein a cross section of the vapor removal channel is sufficient to maintain a pressure difference between the vapor removal channel and the liquid flow channel across the primary wick.

24. The evaporator of claim 18, wherein the heated wall is in intimate contact with the primary wick.

25. The evaporator of claim 18, wherein a thickness of the heated wall is selected to ensure at least substantially complete vaporization at the interface between the primary wick and the heated wall.

26. The evaporator of claim 18, wherein the liquid flow channel is operably coupled to supply the primary wick with liquid from a liquid inlet.

27. The evaporator of claim 26, wherein the liquid flow channel is configured to supply the primary wick with enough liquid to offset liquid vaporized at the interface between the primary wick and the heated wall and liquid vaporized at the liquid barrier wall.

28. The evaporator of claim 18, wherein the secondary wick comprises an opening wherein at least one vapor bubble formed within the vapor vent channel may be swept through the secondary wick and through the liquid flow channel.

29. The evaporator of claim 18, wherein the vapor vent channel is operably coupled to deliver vapor that has vaporized within the primary wick away from the primary wick.

30. The evaporator of claim 18, wherein the primary wick, the heated wall, and the liquid barrier wall are annular and coaxial such that the heated wall is inside the primary wick and the primary wick is inside the liquid barrier wall.