EFFICIENTLY COOL DATA CENTERS AND ELECTRONIC ENCLOSURES USING LOOP HEAT PIPES

• US 20080259566A1
• Filed: 04/15/2008
• Published: 10/23/2008
• Est. Priority Date: 04/16/2007
• Status: Active Grant

• Current Assignee: Stephen Samuel Fried
• Original Assignee: Stephen Samuel Fried
• Inventors: Fried, Stephen Samuel
• Granted Patent: US 7,957,132 B2
• Time in Patent Office: Days
• US Class Current: 361/699
• CPC Class Codes: C12Q 1/34 involving hydrolase
• 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: G01N 2333/924 acting on glycosyl compounds (3.2)
• CPC Class Codes: G01N 2400/10 Polysaccharides, i.e. having more than five saccharide radicals attached to each other by glycosidic linkages; Derivatives thereof, e.g. ethers, esters
• CPC Class Codes: G06F 1/20 Cooling means
• CPC Class Codes: G06F 2200/201 Cooling arrangements using cooling fluid
• CPC Class Codes: H01L 23/427 Cooling by change of state, e.g. use of heat pipes by liquefied gas H01L23/445
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H05K 7/20809 within server blades for removing heat from heat source

Abstract

Disclosed in the present invention are ways for cooling components contained in enclosures that reject 500 or more Watts employing two phase passive heat transfer devices including Loop Heat Pipes and devices we refer to as LHPLs. The methods minimize the amount of energy employed in cooing while at the same time maximizing the quality of heat rejected to the secondary cooling loops that transmit the heat to the outside world. Where data centers provide direct access to chilled water it becomes possible to reject heat directly to cooling towers in locations as hot and humid as Atlanta Ga. eliminating 40% or more of the total energy consumed. The key advances that make this energy efficient performance employ LHPLs that have the smallest possible total thermal resistance, methods that maximize their effectiveness and ancillary devices that minimize the energy consumed in move cooling air.

Claims

1. A device for cooling electronic components in an enclosure comprising:

(a) an electronic enclosure that is supplied with a single coolant produced by an HVAC system that rejects the heat passed to it to the outside world,

(b) a group of electronic components that include at least one or more hot electronic components that can include densely packed hot electronic components that can not be conveniently cooled using conventional electronic cooling devices and the electronic devices needed to support them,

(c) a LHPL whose components have been designed to minimize the LHPL'"'"'s total thermal resistance and that consists of at least an evaporator that contains a wick with vapor escape channels, a liquid compensation chamber, a chamber commonly referred to as an evaporator that encloses the wick and the working fluid where it comes into thermal contact with the device being cooled and makes it possible for the wick to sit as close to the device being cooled as possible, a condenser designed to provide low thermal resistance and return the coolant used to condense its content as hot as possible that can be as simple as a serpentine section of condenser tubing in thermal contact with a well designed finned heat exchanger, a serpentine section of condenser placed in thermal contact with a carefully design liquid cooled cold plate interface, a condenser designed with a liquid coolant in which counter flow principles were applied along with other advanced heat transfer methods and condenser lines that connect the section of the condenser tubing where condensation takes place with the evaporator,

(d) a device used to mount an LHPL evaporator on said hot components that minimizes the thermal resistance between said evaporator and the component being cooled,

(e) a place within the electronic enclosure that can be reached by the pipes that connect the evaporator to the condenser that also provides a suitable location to mount a condenser,

(f) a combination of cooling devices to cool the remainder of the components, said cooling devices selected from the group of conventional electronic cooling devices defined in the specification,

using LHPLs that have been designed and their components situated to minimize their thermal resistances while at the same time making it possible to minimize the enclosures ECOP by the placement of their condensers within or even without the enclosure in such a manner that the energy required to cool the remainder of the components in the system employing conventional electronic devices is minimized which in turn results in a reduction in the amount of coolant required to cool the enclosure causing its temperature to rise as it leaves the enclosure which improves the quality of the heat passed back to the HVAC system that is receiving the heated coolant and which in turn ends up maximizing the TCOP of the enclosure and the HVAC system that is cooling it.

2. The device for cooling electronic components in an enclosure of claim 1 in which the coolant is chilled air and in which the LHPL condensers are located next to the locations in the enclosure where the hot air exits either the enclosure or a region of the enclosure which contains the printed circuit boards that contain the electronic components being cooled and where the air flow velocity can be augmented if needed by conventional electronic cooling devices to guarantee that the LHPL condenser has the cooling air throughput it needs to adequately cool the hot electronic components and where the benefits of claim 1 now end up including the reduction in the ambient temperature of the air within the enclosure end up reducing the quantity and velocity of the air required to cool the electronic components that support the operation of the hot electronic components being cooled using LHPLs with the ultimate result being a reduction in the amount of energy employed to move air, a reduction in the total flow of air through the enclosure, an increase in the temperature of the air leaving the enclosure, a reduction of the ECOP for the enclosure, an improvement in the quality of heat being transmitted to the HVAC system cooling the enclosure and reduction in the TCOP of the building or shelter that contains the enclosure.

3. The device for cooling electronic components in an enclosure of claim 2 whose air cooled condenser can cool more than one set of LHPL condensers lines and which consists of:

(a) a large finned heat exchanger whose base plate is attached to a plurality of fins that face the surface of the electronic enclosure to which it gets mounted and a set of studs that are screwed into the base,

(b) a clamping plate that is provided with thru holes matched to the base plate'"'"'s studs and is used to provide the clamping pressure required to provide thermal contact between a serpentine section of condenser tubing that may be positioned so that the hot vapor enters the serpentine section at the end of the condenser where the hot air leaves it and a set of screws that go over the studs used to clamp the plate to the base plate, whereby by it becomes possible to remove one or more LHPL evaporators and their attached condenser pipe sections one at a time without removing the finned heat exchanger while at the same time providing thermal performance in many systems that is able to cool the hottest electronic components while at the same time reducing the total number of fans or blowers needed to cool the enclosure if LHPLs were not employed.

4. The device for cooling electronic components in an enclosure of claim 2 using the LHPL condenser of claim 3 which has been modified to improve its performance by,

(a) orienting the serpentine condenser line so that its vapor input side is nearest the side where the air leaves the heat exchanger,

(b) machining groves into the base plate down to the fins that continue to allow the serpentine section of condenser tubing to make good contact with the base plate and that prevent heat from moving across the base plate from its hot to cold side,

(c) cutting groves at several locations in the fins that prevent heat from flowing from the hot to the cold side of the fins,

(d) replacing the clamping plate of claim 3 with a finned heat exchanger that is identical to the one that is described in b and c of this claim and can mate with it,

(e) moving the hardware used to clamp the two mating heat exchangers described in b, c and d of this claim to the outer edge of each heat exchanger, whereby improving the thermal performance of the LHPL condenser by enabling counter-flow heat exchange that results in higher exhaust flow air temperatures that in turn increase the quality of the heat passed to the cooling system.

5. The device for cooling electronics components in an enclosure of claim 2 whose LHPL condenser is identical to that of claim 4 with the exception that the slots cut into the base plate in claim 4 have been widened to allow air to flow through it instead of across it and mounting holes have been added so that it may be attached to an electric rotary cooling device that will get mounted on a wall of the enclosure at an air flow exit port thereby making it possible to modify common enclosure designs to employ LHPLs.

6. The device for cooling the electronic components in an enclosure of claim 2 in which the electronic enclosure is now a rack mount chassis that places the LHPL condensers of claims 3 or 4 in the vicinity of an exit port that may also have an electric rotary cooling device mounted on it.

8. The device for cooling electronic components of an enclosure of claim 2 in which an electronic enclosure designed to contain printed circuit boards that can slide into and out of the enclosure and typically are referred to as blades, SBC cards, PCIe cards, PICMG cards, VME boards and similar devices used in computers, telecommunications, COTS computers and embedded computers and which all may contain hot electronic components that require LHPLs to cool them which employ small versions of the condensers described in claims 3 and 4 that can be mounted on such PCB cards near the enclosure'"'"'s air cooling exit port or its electric rotary cooling device.

9. The device for cooling electronic components of an enclosure of claim 2 in which a desktop computer enclosure contains PCBs that include a computer motherboard and its associated PCI cards capable of holding hot electronic components that require LHPLs to cool them and which can use the near by exhaust air ports to mount the LHPL condensers on them as described in claim 5.

10. A device for safely supplying water and evacuating air from a rack mount chassis comprising:

a rack that may be a part of a cabinet in which rack mount chassis are attached to a duct that may contain a chilled water manifold and which may be attached to a plenum with fans that protrude through the cabinets top and plenums that have fans mounted on them that protrude through the cabinets rear door when a cabinet is provided and can provide a connection to a duct that is connected to an HVAC system return air duct and which is provided with duct to chassis seals that make it possible for chassis to be installed in the rack and up to the duct in such a manner that when the duct is evacuated by any of the devices attached to it air does not leak into it and that provides a sealing device that stays with the duct such that when the chassis are removed there are no leaks.

7. The device for cooling electronic components of an enclosure of claim 2 employing the rack mount chassis of claim 6 in which the electric rotary cooling device may be removed and the chassis mounted in a rack that may be enclosed in a cabinet which is attached to the duct in claim 10.

12. The device for safely supplying water and evacuating air from a rack mount chassis of claim 10 and the device for supplying water to a rack mount chassis of claim 11 either of which may have cold plates attached to their water manifolds designed to remain connected to them that may reside between the manifolds and the chassis, that may reside in the chassis and that may have clamped to them LHPL cold spreaders that comprise an LHPL split condenser, heat pipe condenser sections that comprise a heat pipe split condenser and finned cold spreaders that comprise a water cooled split air heat exchanger.

11. A device for supplying water to rack mount chassis comprising:

a rack that may be a part of a cabinet in which rack mount chassis are installed which has a water manifold placed behind the rack mount chassis that can connect to devices that service them with cold water directly and cold plates.

13. A device for cooling the air leaving a rack mount chassis comprising:

the device for safely supplying water and evacuating air from a rack mount chassis of claim 11 and the split air heat exchanger of claim 12 that has been placed in the air flow exit of a rack mount chassis in such a manner that all the air leaving the chassis needs to pass through the heat exchanger.