High conductivity ceramic foam cold plate

• US 8,162,035 B2
• Filed: 04/24/2008
• Issued: 04/24/2012
• Est. Priority Date: 04/20/2006
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Behrens, William Webster, Tucker, Andrew Richard
• Primary Examiner(s): WALBERG, TERESA J
• Application Number:
  US12/108,940
• Publication Number:
  US 20080196869A1
• Time in Patent Office: 1,461 Days
• Field of Search: 165/80.4, 165/80.5, 361/699
• US Class Current: 165/80.4
• CPC Class Codes: B64D 2013/0614 with subsystems for cooling avionics
• CPC Class Codes: F28F 13/003 by using permeable mass, perforated or porous materials F28F13/18 takes precedence
• CPC Class Codes: F28F 21/04 of ceramic; of concrete; of natural stone
• CPC Class Codes: F28F 3/12 Elements constructed in the shape of a hollow panel, e.g. with channels F28D1/02, F28D1/03 take precedence
• CPC Class Codes: H05K 7/20254 Cold plates transferring heat from heat source to coolant
• CPC Class Codes: H05K 7/20509 Multiple-component heat spreaders; Multi-component heat-conducting support plates; Multi-component non-closed heat-conducting structures

Abstract

A cold plate and method for cooling using the cold plate are disclosed. The cold plate includes a housing having hyperporous, microchannel ceramic foam strips disposed therewithin. A plurality of plugs formed from a high thermal conductivity material are disposed into the ceramic foam strips. Heat is transferred in an extremely efficient manner by leveraging the high thermal conductivity of the plugs to transfer the energy deep into a high internal surface area ceramic foam, which in turn transfers the heat to a coolant via convection. Channels between the foam strips form coolant inlet and outlet plenums, which results in minimal coolant pressure drop through the cold plate. In one example, an exemplary cold plate may provide cooling to one or two printed circuit boards. In another example, a cold plate may be disposed within a heat exchanger housing to provide cooling to a fluid.

Claims

1. A cold plate comprising:

a housing defining at inlet port and an outlet port; and

a plurality of foam strips disposed in the housing, each of the foam strips comprising a ceramic foam having a pore size of no more than about 50 micrometers and a porosity of at least about 80 percent and a plurality of thermally conductive plugs disposed in the ceramic foam, the plurality of foam strips configured within the housing such that a coolant provided to the cold plate flows through a width of the foam strips.

2. The cold plate of claim 1, wherein the pore size is about 35 micrometers and the porosity is about 90 percent.

3. The cold plate of claim 1, wherein the ceramic foam comprises silica, aluminum oxide, and aluminoborosilicate fibers.

4. The cold plate of claim 1, wherein the conductive plugs are formed from a material selected from the group comprising boron nitride, aluminum nitride, and alumina.

5. The cold plate of claim 1, further comprising a plurality of plenums disposed within the housing between the foam strips.

6. The cold plate of claim 1, wherein the conductive plugs extend through the foam strips and are in thermal communication with the top and bottom cover plates of the cold plate housing.

7. A method of cooling, the method comprising:

flowing a coolant into a housing;

flowing the coolant across widths of a plurality of foam strips disposed within the housing, the foam strips comprising a ceramic foam having a pore size of no more than about 50 micrometers and a porosity of at least about 80 percent and a plurality of conductive plugs; and

discharging the coolant from the housing.

8. The method of claim 7, further comprising providing the coolant to the plurality of foam strips via a plurality of plenums.

9. The method of claim 7, wherein the ceramic foam comprises silica, aluminum oxide, and aluminoborosilicate fibers.

10. The method of claim 7, wherein the conductive plugs are formed from a material selected from the group comprising boron nitride, aluminum nitride, and alumina.

11. The method of claim 7, further comprising a plurality of plenums disposed within the housing between the foam strips.

12. The method of claim 7, wherein the conductive plugs extend through the foam strips and are in thermal communication with the top and bottom cover plates of the cold plate housing.

13. The method of claim 7, further comprising thermally contacting an electronic component with the housing.

14. The method of claim 7, wherein the coolant is air.

15. The method of claim 7, further comprising cooling a fluid by contacting the fluid with the housing.

16. A circuit board assembly comprising:

at least one circuit board having a first surface and a second surface, the circuit board having at least one printed circuit mounted on the first surface of the circuit board; and

a cold plate comprising a housing having a top and a top and bottom cover plates, the bottom cover plate in thermal communication with the second surface of the at least one circuit board;

wherein the cold plate further comprises a plurality of foam strips disposed in the housing, each of the foam strips comprising a ceramic foam having a pore size of no more than about 50 micrometers and a porosity of at least about 80 percent and a plurality of conductive plugs, the plurality of foam strips configured within the housing such that a coolant provided to the cold plate flows through a width of the foam strips.

17. The circuit board assembly of claim 16, further comprising a second circuit board including a first surface and a second surface, the second circuit board having at least one printed circuit board mounted on the first surface, the top cover plate in thermal communication with the second surface of the second circuit board.

18. The circuit board assembly of claim 16, wherein the ceramic foam has a pore size of about 35 micrometers and the porosity is about 90 percent.

19. The circuit board assembly of claim 16, wherein the ceramic foam comprises silica, aluminum oxide, and aluminoborosilicate fibers.

20. The circuit board assembly of claim 16, wherein the conductive plugs are formed from a material selected from the group comprising boron nitride, aluminum nitride, and alumina.

22. The heat exchanger of claim 20, wherein:

the cold plate housing further includes a second cold plate inlet port for the second fluid and a second cold plate outlet port for the second fluid; and

the cold plate further includes a second plurality of foam strips containing thermally conductive plugs, the first and second pluralities of such foam strips being arranged within the housing such that the second fluid from the first cold plate inlet is flowable through widths of the foam strips in the first plurality of foam strips and the second fluid from the second cold plate inlet is flowable through widths of the foam strips in the second plurality of foam strips.

21. A heat exchanger comprising:

a heat exchanger housing having at least one heat exchanger inlet port for a first fluid and at least one heat exchanger outlet port for the first fluid; and

at least one cold plate disposed within the heat exchanger housing intermediate the heat exchanger inlet port and the heat exchanger outlet port, such that the first fluid is flowable in thermal communication with the cold plate;

wherein the cold plate comprises;

a cold plate housing defining at least a first cold plate inlet port for a second fluid and at least a first cold plate outlet port for the second fluid; and

a plurality of foam strips disposed in the cold plate housing, each of the foam strips comprising a ceramic foam having pore size of no more than about 50 micrometers and a porosity of at least about 80 percent and a plurality of conductive plugs disposed in the ceramic foam, the plurality of foam strips configured within the housing such that a coolant provided to the cold plate flows through a width of the foam strips.

23. The heat exchanger of claim 21, wherein the pore size is about 35 micrometers and the porosity is about 90 percent.

24. The heat exchanger of claim 21, wherein the ceramic foam comprises silica, aluminum oxide, and aluminoborosilicate fibers.

25. The heat exchanger of claim 21, wherein the plugs are formed from a material selected from the group comprising boron nitride, aluminum nitride, and alumina.

26. The heat exchanger of claim 21, further comprising a plurality of plenums disposed within the housing.

27. The heat exchanger of claim 21, wherein the conductive plugs extend through the foam strips and are in thermal communication with the top and bottom cover plates of the cold plate housing.