Cooling assembly for electronics drawer using passive fluid loop and air-cooled cover

• US 6,967,841 B1
• Filed: 05/07/2004
• Issued: 11/22/2005
• Est. Priority Date: 05/07/2004
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Simons, Robert E., Ellsworth, Michael J. Jr., Chu, Richard C., Schmidt, Roger R.
• Primary Examiner(s): CHERVINSKY, BORIS LEO
• Application Number:
  US10/841,748
• Publication Number:
  US 20050248922A1
• Time in Patent Office: 564 Days
• Field of Search: 361/689, 361/690, 361695-700, 361715-721, 257/714, 257/715, 174/15.1, 174/15.2, 174/16.1, 174/16.3, 165/80.4, 165/104.17, 165/104.26
• US Class Current: 361/700
• CPC Class Codes: H05K 7/20727 within server blades for removing heat from heat source
• CPC Class Codes: H05K 7/20809 within server blades for removing heat from heat source

Abstract

A cooling apparatus for electronic drawers utilizing a passive fluid cooling loop in conjunction with an air cooled drawer cover. The air cooled cover provides an increased surface area from which to transfer heat to cooling air flowing through the drawer. The increased cooling surface uses available space within the drawer, which may be other than immediately adjacent to a high power device within the drawer. The passive fluid cooling loop provides heat transfer from the high power device to the air cooled cover assembly, allowing placement of the air cooled cover assembly other than immediately adjacent to the high power device. The cooling apparatus is easily disengaged from the electronics drawer, providing access to devices within the drawer.

Claims

1. A cooling apparatus comprising:

a high thermal conductivity electronics drawer cover;

a plurality of high thermal conductivity cooling fins in thermal contact with an underside of said cover;

a fluid cooling loop including;

a plurality of high heat transfer fluid channels in thermal contact with said cover underside, said channels located in proximity to said fins;

a flexible vapor conduit, a first end of said vapor conduit being in fluid flow communication with a first end of said channels;

a high heat transfer boiling chamber in fluid flow communication with a second end of said vapor conduit;

at least one flexible condensate return conduit in fluid flow communication with a second end of said fluid channels, said return conduit also in fluid flow communication with said boiling chamber; and

a mechanical biasing component in mechanical contact with said underside of said cover, and with an upper side of said boiling chamber.

2. The apparatus of claim 1, wherein said flexible vapor conduit is a metallic bellows, and said mechanical biasing component is also said metallic bellows.

3. The apparatus of claim 1, wherein said mechanical biasing component is a spring.

4. The apparatus of claim 1, further comprising a cooling fluid.

5. The apparatus of claim 4, wherein said cooling fluid is at a pressure below atmospheric pressure.

6. The apparatus of claim 5, wherein said cooling fluid boils at a temperature no higher than 60C.

7. The apparatus of claim 4, wherein said cooling fluid is selected from the group consisting of water, brine, refrigerant, and fluorocarbons.

8. The apparatus of claim 1, wherein said boiling chamber is constructed of a material selected from the group consisting of copper, aluminum, stainless steel, and nickel.

9. The apparatus of claim 1, said fluid flow channels further comprising:

an inlet plenum at said channel first end, said inlet plenum distributing fluid from said vapor conduit to said plurality of channels; and

an outlet plenum at said channel second end, said outlet plenum collecting fluid from said plurality of channels.

10. The apparatus of claim 1, wherein said flexible return conduit includes at least one inflexible portion and at least one flexible portion.

11. The apparatus of claim 1, wherein said channels and said fins are interdigitated.

12. A cooled electronic drawer apparatus comprising:

a drawer frame, said drawer frame including a bottom, side components, a front air inlet component, and a rear air outlet component;

an electronics board assembly connected to said drawer frame, said board assembly including a plurality of electronic components, said plurality of components including at least one high power component;

at least one air moving device connected to said drawer frame;

a cooling assembly disengagably connected to said drawer frame, said cooling assembly including;

a high thermal conductivity drawer cover;

a plurality of high thermal conductivity cooling fins in thermal contact with an underside of said cover;

a fluid cooling loop including;

a plurality of high heat transfer fluid channels in thermal contact with said cover underside, said channels located in proximity to said fins;

a flexible vapor conduit, a first end of said vapor conduit being in fluid flow communication with a first end of said channels;

a high heat transfer boiling chamber in fluid flow communication with a second end of said vapor conduit;

at least one flexible condensate return conduit in fluid flow communication with a second end of said fluid channels, said return conduit also in fluid flow communication with said boiling chamber; and

a mechanical biasing component in mechanical contact with said underside of said cover, and with an upper side of said boiling chamber, and

wherein said boiling chamber is in thermal contact with said at least one high power component when said cover is in a closed position.

13. The apparatus of claim 12, wherein said mechanical biasing component is compressed when said cover is in a closed position, said mechanical biasing component exerting a compressive force between said boiling chamber and said high power component.

14. The apparatus of claim 12, wherein said flexible vapor conduit is a metallic bellows, and said mechanical biasing component is also said metallic bellows.

15. The apparatus of claim 12, wherein said mechanical biasing component is a spring.

16. The apparatus of claim 12, wherein said electronics board assembly includes a plurality of high power components.

17. The apparatus of claim 12, further comprising a cooling fluid.

18. The apparatus of claim 12, wherein said cover is detachable from said drawer frame.

19. The apparatus of claim 18, wherein said cover is pivotally mounted to one of said frame components.

20. The apparatus of claim 12, wherein said cover is hingably mounted to one of said frame components.

21. A cooled electronic rack system comprising:

a rack frame;

at least one electronic drawer slidably mounted within said frame, said drawer including;

a drawer frame, said drawer frame including a bottom, side components, a front air inlet component, and a rear air outlet component;

an electronics board assembly connected to said drawer frame, said board assembly including a plurality of electronic components, said plurality of components including at least one high power component;

at least one air moving device connected to said drawer frame;

a cooling assembly disengagably connected to said drawer frame, said cooling assembly including;

a high thermal conductivity drawer cover;

a plurality of cooling fins in thermal contact with an underside of said cover;

a fluid cooling loop including;

a plurality of high heat transfer fluid channels in thermal contact with said cover underside, said channels located in proximity to said fins;

a flexible vapor conduit, a first end of said vapor conduit being in fluid flow communication with a first end of said channels;

a high heat transfer boiling chamber in fluid flow communication with a second end of said vapor conduit;

at least one flexible condensate return conduit in fluid flow communication with a second end of said fluid channels, said return conduit also in fluid flow communication with said boiling chamber;

a mechanical biasing component in mechanical contact with said underside of said cover, and with an upper side of said boiling chamber, and

wherein said boiling chamber is in thermal contact with said at least one high power component when said cover is in a closed position.

22. The system of claim 21, including a plurality of said electronic drawers.