Evaporator For Use In A Heat Transfer System

• US 20070131388A1
• Filed: 12/09/2005
• Published: 06/14/2007
• Est. Priority Date: 12/09/2005
• Status: Active Grant

• Current Assignee: Northrop Grumman Systems Corporation (Northrop Grumman Corporation)
• Original Assignee: Swales & Associates, Inc.
• Inventors: Baker, Jeff, Khrustalev, Dmitry, Cologer, Pete, Stouffer, Charles, Feenan, Dave, Garzon, Jessica, Beres, Matthew
• Granted Patent: US 7,661,464 B2
• Time in Patent Office: Days
• US Class Current: 165/104.260
• CPC Class Codes: F28D 15/0266 with separate evaporating and condensing chambers connected by at least one conduit; Loop-type heat pipes; with multiple or common evaporating or condensing chambers F28D15/043 takes precedence
• CPC Class Codes: F28D 15/043 forming loops, e.g. capillary pumped loops

Abstract

An evaporator includes a cylindrical barrier wall, and a cap that fits at an end of the cylindrical barrier wall. The cylindrical barrier wall defines a central axial opening and an outer cylindrical surface. The cap includes an outer surface that is external to the central axial opening and an inner surface that abuts the central axial opening. A portion of the outer cylindrical surface is configured to define a liquid port extending through the outer cylindrical surface of the cylindrical barrier wall.

Claims

1. An evaporator comprising:

a cylindrical barrier wall defining a central axial opening and an outer cylindrical surface;

a cap that fits at an end of the cylindrical barrier wall, the cap including an outer surface that is external to the central axial opening and an inner surface that abuts the central axial opening; and

a portion of the outer cylindrical surface configured to define a liquid port extending through the outer cylindrical surface of the cylindrical barrier wall.

2. The evaporator of claim 1 further comprising a cylindrical wick that fits within the central axial opening, wherein the liquid port extends into the cylindrical wick.

3. The evaporator of claim 1 further comprising a sleeve that is attached to liquid port of the cylindrical barrier wall.

4. The evaporator of claim 3 wherein the sleeve is welded to the cylindrical barrier wall at the outer cylindrical surface.

5. The evaporator of claim 1 further comprising:

a cylindrical wick that fits within the central axial opening, wherein the liquid port extends into the cylindrical wick;

an outer sleeve defining a sleeve axis; and

a tube within the outer sleeve and extending along the sleeve axis;

wherein;

a first region of the tube is attached to the outer sleeve and a second region of the tube is attached to the cylindrical wick; and

the outer sleeve is attached to liquid port of the cylindrical barrier wall.

6. The evaporator of claim 5 wherein the second region of the tube is sealed to the cylindrical wick in such manner that a gap between the tube at the second region and the cylindrical wick is smaller than a radius of the pores within the cylindrical wick.

7. The evaporator of claim 5 wherein:

the tube is made of a first metal at the first region and the tube is made of a second metal at the second region;

the first region of the tube is welded to the outer sleeve; and

the second region of the tube is welded to the cylindrical wick.

8. The evaporator of claim 1 further comprising a heat-receiving saddle that covers at least part of the outer cylindrical surface of the cylindrical barrier wall.

10. The evaporator of claim 1 further comprising a cylindrical wick that fits within the central axial opening and that defines a central axial channel, wherein the liquid port extends into the cylindrical wick and into the central axial channel.

20. The evaporator of claim 1 further comprising a vapor port extending through the outer cylindrical surface of the cylindrical barrier wall.

25. The evaporator of claim 8 wherein the heat-receiving saddle is made of a material having a coefficient of thermal expansion of about 2 times the magnitude of the coefficient of thermal expansion of the heat source applied to the evaporator.

9. (canceled)

11-19. -19. (canceled)

21-24. -24. (canceled)

26-36. -36. (canceled)

37. A method of transferring heat, the method comprising:

flowing liquid through a liquid flow channel that is defined within a wick;

flowing the liquid from the liquid flow channel through the wick;

evaporating at least some of the liquid at a vapor removal channel that is defined at an interface between the wick and a cylindrical barrier wall; and

inputting heat energy onto an exterior heat-absorbing surface of a cylindrical barrier wall, wherein the exterior heat-absorbing surface extends the full length of the cylindrical barrier wall.

38-42. -42. (canceled)

43. A heat transfer system comprising:

a condenser; and

an evaporator network including two or more evaporators fluidly connected to each other and including at least one evaporator that is coupled to a liquid line that is coupled to the condenser and at least one evaporator that is coupled to a vapor line that is fluidly coupled to the condenser, wherein each evaporator in the network comprises;

a cylindrical barrier wall defining a central axial opening and an outer cylindrical surface;

a cylindrical wick that fits within the central axial opening;

a cap that fits at an end of the cylindrical barrier wall, the cap including an outer surface that is external to the central axial opening and an inner surface that abuts the central axial opening; and

a liquid port extending through the outer cylindrical surface of the cylindrical barrier wall and into the cylindrical wick.

44. The heat transfer system of claim 43 further comprising a pumping system coupled to the condenser and the evaporator.

45. The heat transfer system of claim 44 wherein the pumping system includes a mechanical pump within the liquid line.

46. The heat transfer system of claim 44 wherein the pumping system includes a passive secondary heat transfer loop including a secondary evaporator.

47. The heat transfer system of claim 43 wherein the two or more evaporators are connected in series such that the working fluid is able to flow into and out of each evaporator through its liquid port.

48. The heat transfer system of claim 47 wherein the evaporators liquid flows from one evaporator to the next evaporator.

49. The heat transfer system of claim 47 further comprising a reservoir, wherein the liquid coming out of the last evaporator in the series flows through a separate line into either the condenser or the fluid reservoir.

50. The heat transfer system of claim 47 wherein each evaporator in the network includes a vapor port, with each vapor port being joined together to form a single vapor line that couples to the condenser.

51. The heat transfer system of claim 43 wherein the liquid mass flow rate into each evaporator exceeds the vapor mass flow rate coming of each evaporator such that the liquid mass flow rate coming of each evaporator is greater than zero.

52. The heat transfer system of claim 43 further comprising a fluid reservoir that is hydraulically linked to the condenser.

53-55. -55. (canceled)