US20100275618A1

US20100275618A1 - System and method for cooling fluid distribution

Info

Publication number: US20100275618A1
Application number: US12/433,430
Authority: US
Inventors: Abdlmonem Beitelmal; Cullen E. Bash
Original assignee: Hewlett Packard Development Co LP
Current assignee: Hewlett Packard Development Co LP
Priority date: 2009-04-30
Filing date: 2009-04-30
Publication date: 2010-11-04

Abstract

A system for distributing a cooling fluid in a room containing at least one heat generating component includes a primary heat exchanger having an inlet for receiving the cooling fluid, a heat exchange section configured to facilitate exchange of heat between airflow in the room and the cooling fluid, and an outlet for exhausting heated cooling fluid from the heat exchange section. The system also includes a secondary heat exchanger having a receiving section connected to the second section of a cooling fluid line for receiving heated cooling fluid, a heat exchange section configured to facilitate exchange of heat between the at least one heat generating component and the heated cooling fluid, and an exhaust section configured to exhaust secondarily heated cooling fluid.

Description

CROSS-REFERENCES

The present application has the same Assignee and shares some common subject matter with U.S. Patent Application Publication No. 2004/0020224, entitled “Cooling System with Evaporators Distributed in Parallel”, filed on Dec. 4, 2002, by Bash et al.; U.S. Patent Application Publication No. 2004/0020226, entitled “Cooling System with Evaporators Distributed in Series”, filed on Dec. 4, 2002, by Bash et al.; U.S. patent application Ser. No. 11/142,557 (Attorney Docket No. 200403658-1), entitled “Air-Cooled Heat Generating Device Airflow Control System”, filed on Jun. 1, 2005; and U.S. patent application Ser. No. 11/142,558 (Attorney Docket No. 200403657-1), entitled “Refrigeration System with Parallel Evaporators and Variable Speed Compressor”, filed on Jun. 1, 2005. The disclosures of the above-listed applications are incorporated by reference in their entireties.

BACKGROUND

A data center may be defined as a location, e.g., room, that houses computer systems arranged in a number of racks. A standard rack may be defined as an Electronics Industry Association (EIA) enclosure, 78 in. (2 meters) wide, 24 in. (0.61 meter) wide and 30 in. (0.76 meter) deep. The computer systems typically include a number of components, e.g., one or more of printed circuit boards (PCBs), mass storage devices, power supplies, processors, micro-controllers, semi-conductor devices, and the like, that may dissipate relatively significant amounts of heat during the operation of the respective components.
Conventional data centers are typically cooled by operation of one or more air conditioning units. The one or more air conditioning units typically receive cooled cooling fluid from a separate cooling apparatus and use the cooled cooling fluid to cool airflow in the data center. In addition, the heated cooling fluid is returned back to the cooling apparatus to be re-cooled and used again in cooling the airflow.

BRIEF DESCRIPTION OF THE DRAWINGS

Features of the present invention will become apparent to those skilled in the art from the following description with reference to the figures, in which:

FIGS. 1A-1D show cross-sectional side views of a room containing a cooling fluid distribution system, according to various embodiments of the invention;

FIGS. 2A and 2B show alternative schematic diagrams of the cooling fluid distribution system depicted in FIGS. 1A-1D, according to embodiments of the invention;

FIGS. 3A-3D show respective schematic diagrams of portions of the secondary heat exchanger depicted in FIGS. 1A-1D, 2A, and 2B, according to embodiments of the invention; and

FIG. 4 illustrates a flow diagram of a method of distributing cooling fluid in a room containing a cooling fluid distribution system, according to an embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

For simplicity and illustrative purposes, the present invention is described by referring mainly to an exemplary embodiment thereof. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It will be apparent however, to one of ordinary skill in the art, that the present invention may be practiced without limitation to these specific details. In other instances, well known methods and structures have not been described in detail so as not to unnecessarily obscure the present invention.
Disclosed herein are a system and method of distributing a cooling fluid in a room containing at least one heat generating component. The cooling fluid distribution system includes a primary heat exchanger, a secondary heat exchanger, and a cooling fluid line connecting the primary heat exchanger to the secondary heat exchanger. In one embodiment, the primary heat exchanger is configured to cool airflow supplied into the room through heat exchange with the cooling fluid and the secondary heat exchanger is configured to cool the at least one heat generating component through heat exchange with cooling fluid that has been heated in the primary heat exchanger.
Thus, the secondary heat exchanger is configured to provide an additional level of cooling to the at least one heat generating component beyond the cooling afforded by the cool airflow supplied by the primary heat exchanger. In addition, the secondary heat exchanger is configured to provide the additional level of cooling through use of the waste heated cooling fluid from the primary heat exchanger. The secondary heat exchanger is able to utilize the heated cooling fluid from the primary heat exchanger because the heated cooling fluid remains at a sufficiently low temperature with respect to the temperature of the at least one heat generating component.
Through implementation of the systems and method disclosed herein, the secondary heat exchanger is able to utilize available cooling capacity that would otherwise have been wasted by utilizing the heated cooling fluid from the primary heat exchanger. In addition, because the secondarily heated cooling fluid is at a relatively higher temperature than the heated cooling fluid, a cooling apparatus configured to cool the cooling fluid may operate at a relatively higher efficiency. Moreover, the overall cooling system infrastructure cost may be substantially reduced because various parts of the infrastructure may be re-used and the water flow capacity may not need to be increased due to increased demand.
With reference first to FIG. 1A, there is shown a cross-sectional side view of a room 100 containing a cooling fluid distribution system 120, according to an example. It should be understood that the room 100 and the cooling fluid distribution system 120 may include additional components and that some of the components described herein may be removed and/or modified without departing from a scope of the room 100 and the cooling fluid distribution system 120.
As depicted in FIG. 1A, the room 100, for instance, a data center, houses a rack 102, which may house a plurality of heat generating components (not shown), for instance, processors, micro-controllers, memories, semi-conductor devices, and the like. The components may be elements of a plurality of subsystems (not shown), for instance, computers, servers, etc. The subsystems and the components may be implemented to perform various electronic, for instance, computing, switching, routing, displaying, and the like, functions. In the performance of these electronic functions, the components, and therefore the subsystems, may dissipate relatively large amounts of heat.
The rack 102 is depicted as being positioned on a raised floor 104 that forms a space 106 above a subfloor of the room 100. The space 106 provides an area in which wires, tubes, and the like may be placed. The space 106 also operates as a plenum for the delivery of cooled airflow 108 through a vent tile 110 into the room 100 and into the rack 102 to cool the heat generating components contained therein.
The cooling fluid distribution system 120 includes a primary heat exchanger 130, a cooling fluid line 140, and a secondary heat exchanger 150. The cooling fluid distribution system 120 may also include a cooling apparatus 160. The cooling fluid line 140 is depicted as comprising a loop that runs through each of the primary heat exchanger 130, secondary heat exchanger 150 and the cooling apparatus 160. Although not explicitly shown, a cooling fluid, for instance chilled water, R134a, ethylene glycol mixture, and the like, is contained in the cooling fluid line 140 and is configured to be circulated through the loop. In addition, one or more pumps 142 may be provided along the cooling fluid line 140 to pressurize the cooling fluid contained therein and cause the cooling fluid to be circulated through the cooling fluid line 140.
The cooling apparatus 160 is configured to receive heated cooling fluid from either or both of the primary heat exchanger 130 and the secondary heat exchanger 150 and to cool the heated cooling fluid. The cooling apparatus 160 may comprise any reasonably suitable type of cooling apparatus designed to adequately cool the cooling fluid to, for instance, temperatures around 42-48° F. The cooling apparatus 160 may include a cooling apparatus that implements an air conditioner, a heat exchanger, a heat pump, a variable capacity chiller, an evaporative cooling system, and the like. By way of particular example, the cooling apparatus 160 may comprise a closed-loop refrigeration cycle apparatus having a heat transfer section where the heat from the cooling fluid in a cooling fluid line 140 may be transferred to a refrigerant contained in the closed-loop refrigeration cycle apparatus.
Although the cooling apparatus 160 has been illustrated as being located outside of the room 100, it should be understood that the cooling apparatus 160 may be positioned within the room 100 without deviating from the scope of the room 100 and cooling fluid distribution system 120 depicted in FIG. 1A.
The primary heat exchanger 130 includes an inlet 132 for receiving cooled cooling fluid 170 from the cooling apparatus 160, a heat exchange section 134 that facilitates exchange of heat between heated airflow 112 received into the primary heat exchanger 130 and the cooled cooling fluid 170, and an outlet 136 for exhausting heated cooling fluid 172 from the heat exchange section 134. The primary heat exchanger 130 may comprise any reasonably suitable apparatus configured to receive heated airflow 112, to cool the heated airflow 112, and to provide cooled airflow 108 into the room 100. The primary heat exchanger 130 may thus comprise an air conditioning unit, a data center air handler, etc.
The primary heat exchanger 130 of the cooling distribution system 120 may also comprise, for instance, a ceiling mounted heat exchanger unit. An example of this configuration is depicted in FIG. 1B, which shows a cross-sectional side view of a room 100 containing the cooling fluid distribution system 120. As shown therein, the primary heat exchanger 130 is a ceiling based heat exchanger unit configured to deliver cool airflow 108 from above the rack 102. A more detailed description of various manners in which the primary heat exchanger 130 may be positioned and operated as a ceiling mounted heat exchanger unit is described in U.S. Patent Application Publication No. 2004/0020226.
The secondary heat exchanger 150 includes an inlet 152 for receiving heated cooling fluid 172 from the outlet 136 of the primary heat exchanger 130, a heat exchange section 154 that facilitates exchange of heat between cooled airflow supplied into the rack 102 and the heated cooling fluid 172 received from the primary heat exchanger 130, and an exhaust section for exhausting the secondarily heated cooling fluid 174 from the secondary heat exchanger 150. Although the secondary heat exchanger 150 has been depicted as being positioned at an inlet of the rack 102, the secondary heat exchanger 150 may be positioned at the exhaust of the rack 102 to thereby cool airflow heated in the rack 102. The secondary heat exchanger 150 may comprise various other configurations as discussed in greater detail herein below.
As such, the secondary heat exchanger 150 is configured to utilize the heated cooling fluid 172 from the primary heat exchanger 130 to further cool the heat generating components (not shown) housed in the rack 102. The heated cooling fluid 172 in the secondary heat exchanger 150 may be able to cool the airflow supplied into the rack 102 because the airflow temperature may be relatively higher than the temperature of the heated cooling fluid 172. The airflow temperature is often affected by recirculation of heated airflow into the cool airflow supplied into the rack 102, which increases the temperature of the cool airflow and which may cause the cool airflow temperature to be substantially higher than the heated cooling fluid 172 temperature.
In another example, and as shown in FIG. 1C, the primary heat exchanger 130 may be positioned at the inlet of the rack 102 to cool airflow supplied directly into the rack 102. In this example, the secondary heat exchanger 150 may be positioned within the rack 102 to directly cool one or more heat generating components 320 contained in the rack 102.
In a further example, and as shown in FIG. 1D, the primary heat exchanger 130 may be positioned at the inlet of the rack 102, similarly to FIG. 1C. However, in the room 100 depicted in FIG. 1D, the secondary heat exchanger is positioned at the exhaust of the rack 102 to cool airflow exhausted from the one or more heat generating components 320 contained in the rack.
In all of the examples above, the secondarily heated cooling fluid 174 may be returned to the cooling apparatus 160 to be cooled again and the process discussed above may be repeated to continuously provide cooling resources to the components contained in the room 100, while utilizing the waste heated cooling fluid 172 from the primary heat exchanger 130.
Although the rooms 100 depicted in FIGS. 1A-1D are illustrated as containing a single rack 102, a single primary heat exchanger 130 and a single secondary heat exchanger 150, it should be understood that the room 100 may contain any number of racks 102, primary heat exchangers 130, and secondary heat exchangers 150 without deviating from scope of the rooms 100 and the cooling fluid distribution system 120 depicted therein. In addition, the cooling fluid line 140 may be connected from the primary heat exchanger 130 to a plurality of secondary heat exchangers 150 to thereby enable the heated cooling fluid from the primary heat exchanger 130 to be delivered to the plurality of secondary heat exchangers 150.
Turning now to FIGS. 2A and 2B, there are shown alternative schematic diagrams of the cooling fluid distribution system 120, according to two examples. It should be understood that the cooling fluid distribution systems 120 depicted in FIGS. 2A and 2B may include additional components and that some of the components described herein may be removed and/or modified without departing from scopes of the cooling fluid distribution systems 120.
The cooling fluid distribution system 120 depicted in FIGS. 2A and 2B include a primary heat exchanger 130, a plurality of secondary heat exchangers 150, and a cooling fluid line 140. As such, the cooling fluid distribution system 120 depicted in FIGS. 2A and 2B include all of the features discussed above with respect to the cooling fluid distribution system 120 depicted in FIGS. 1A-1D. As also discussed above, one or more pumps 142 may be positioned along either or both of the cooling fluid line 140 and the cooling fluid sub-lines 144 to cause the cooling fluid to be circulated through the cooling fluid line 140 and the cooling fluid sub-lines 144.
With particular reference now to FIG. 2A, the primary heat exchanger 130 is depicted as being connected to the plurality of secondary heat exchangers 150 through a plurality of cooling fluid sub-lines 144. More particularly, the plurality of secondary heat exchangers 150 are depicted as each receiving heated cooling fluid 170 from the primary heat exchanger 130 and are thus considered as being in a parallel relationship with respect to each other along the cooling fluid sub-lines 144. As such, each of the secondary heat exchangers 150 receives the heated cooling fluid 170 directly from the primary heat exchanger 130.
Turning now to FIG. 2B, the primary heat exchanger 130 is depicted as being connected to a first secondary heat exchanger 150 and the first secondary heat exchanger 150 is depicted as being connected to a second secondary heat exchanger 150 along the cooling fluid line 140. In other words, the first secondary heat exchanger 150 is in a serial relationship with respect to the second secondary heat exchanger 150 along the cooling fluid line 140. As such, the second secondary heat exchanger 150 is configured to receive secondarily heated cooling fluid 174 exhausted from the first secondary heat exchanger 150 and the first secondary heat exchanger 150 may be capable of cooling higher heat loads as compared with the second secondary heat exchanger 150. Thus, in one example, the first secondary heat exchanger 150 is configured to cool one or more components that generate greater amounts of heat, are more critical, etc., as compared with one or more components that the second secondary heat exchanger 150 is configured to cool.
In both of the configurations depicted in FIGS. 2A and 2B, the secondary heat exchangers 150 may comprise any of a liquid to air heat exchanger, a liquid to liquid heat exchanger, a cold plate, and a liquid cooled rack heat exchanger as discussed with respect to FIGS. 3A-3D below. In addition, although FIGS. 2A and 2B have been depicted as having particular numbers of primary heat exchangers 130 and secondary heat exchangers 150, it should be understood that the cooling fluid distribution systems 120 depicted therein may include any number of primary heat exchangers 130 and secondary heat exchangers 150 without departing from scopes of the cooling fluid distribution systems 120 depicted in FIGS. 2A and 2B. Moreover, various aspects of the configurations depicted in FIGS. 2A and 2B may be merged with each other. Thus, for instance, in FIG. 2B, the secondary heat exchangers 150 may comprise a plurality of secondary heat exchangers arranged in parallel with respect to each other as shown in FIG. 2A.
With reference now to FIGS. 3A-3D, there are respectively shown portions of the cooling fluid distribution system 120, according to various examples. It should be understood that the portions of the cooling fluid distribution systems 120 depicted in FIGS. 3A-3D may include additional components and that some of the components described herein may be removed and/or modified without departing from scopes of the cooling fluid distribution systems 120 depicted in FIGS. 3A-3D.
With reference first to FIG. 3A, the secondary heat exchanger 150 is depicted as being positioned within the path of cool airflow 304 supplied into a rack 102. In this regard, the heat exchange section 154 of the secondary heat exchanger 150 is configured to further cool the cool airflow 304 prior to being supplied into the rack 102. The heat exchange section 154 may thus be provided with a plurality of fins or other means for facilitating the transfer of heat from the cool airflow 304 to the heated cooling fluid 172.
As the cool airflow 304 flows through the rack 102 and the heat generating components 320 housed therein, the cool airflow 304 may become heated and may be exhausted as heated airflow 306 from a rear section of the rack 102. The transfer of heat from the heat generating components 320 to the airflow 304/306 may dissipate heat from the heat generating components 320, thereby cooling the heat generating components 320.
In addition, or alternatively, a secondary heat exchanger 150 may be positioned at the rear section of the rack 102 to thereby cool the heated airflow 306 exhausted from the heat generating components 320. In this example, the temperature of the heated airflow 306 may be reduced, for instance, when the heated airflow 306 is likely to be recirculated back into the rack 102 or into an inlet of another rack.
With reference now to FIG. 3B, the secondary heat exchanger 150 is depicted as being positioned within the rack 102. In this embodiment, the secondary heat exchanger 150 is a liquid to air heat exchanger and comprises a plurality of heat exchange sections 154 configured to cool specific heat generating components 320 housed within the rack 102. More particularly, for instance, the heat exchange sections 154 of the secondary heat exchanger 150 may be in direct contact with one or more of the heat generating components 320 to enable heat from the heat generating components 320 to be directly transferred into the heated cooling fluid 172 at the heat exchange sections 154.
Although the secondary heat exchanger 150 has been depicted as running through a rack 102, it should be understood that the secondary heat exchanger 150 may also run through individual heat generating components 320 without departing from the secondary heat exchanger 150 depicted in FIG. 3B. In this example, the heat exchange sections 154 may be positioned to collect heat from particular elements, such as, processors, hard drives, power supplies, etc., of a particular heat generating component 320.
Turning now to FIG. 3C, the heat generating component 320 is depicted as comprising, for instance, a server, a disk drive, etc., or an element housed in any of these devices, such as, a processor, a hard drive, a power supply, etc. In addition, the heat exchange section 154 of the secondary heat exchanger 150 is depicted as being in direct contact with the heat generating component 320. As such, the secondary heat exchanger 150 may be considered as being a cold plate.
Turning now to FIG. 3D, the heat exchange section 154 of the secondary heat exchanger 150 is depicted as being in thermal contact with a tertiary heat exchanger 330 positioned to cool a heat generating component 320. The tertiary heat exchanger 330 may include a loop containing a separate cooling fluid configured to be conveyed to different locations in the heat generating component 320. The tertiary heat exchanger 330 may be configured in any of the configurations depicted in FIGS. 2A, 2B, and 3A-3C.
Generally speaking, the plurality of secondary heat exchangers 150 may be configured for various cooling applications according to the temperature of the heated cooling fluid 172 and/or secondarily heated cooling fluid 174 supplied by the preceding primary and/or secondary heat exchanger 130, 150 in series along the cooling fluid distribution line 140. For instance, less critical heat generating components 320 may be positioned to receive heated cooling fluid 172, 174 having relatively higher temperatures.
By way of particular example, cold plates that are used to cool servers and/or components contained therein, may utilize heated cooling fluid 172, 174 with temperatures in the range of about 95° F. to 100° F. from one or more primary and/or secondary heat exchangers 130, 150 located upstream of the cold plates.
With reference now to FIG. 4, there is shown a flow diagram of a method 400 of distributing cooling fluid in a room 100 having a cooling fluid distribution system 120, according to an example. It is to be understood that the following description of the method 400 is but one manner of a variety of different manners in which an example of the invention may be practiced. It should also be apparent to those of ordinary skill in the art that the method 400 represents a generalized illustration and that other steps may be added or existing steps may be removed, modified or rearranged without departing from a scope of the method 400.
At step 402, a primary heat exchanger 130 is supplied with a cooled cooling fluid 170 from a cooling apparatus 160. At step 404, the heat exchange section 134 facilitates exchange of heat between heated airflow 112 in the room 100 and the cooled cooling fluid 170.
At step 406, heated cooling fluid 172 is conveyed from the primary heat exchanger 130 to the secondary heat exchanger 150 through the cooling fluid line 140. In addition, at step 408, one or more heat generating components 320 contained in the room 100 are cooled through exchange of heat with the heated cooling fluid 172. At step 410, the secondarily heated cooling fluid 174 is conveyed back to the cooling apparatus 160. In addition, steps 402-410 may be repeated in a substantially continuous manner to substantially continuously cool the heat generating components 320 housed in the room 100.
What has been described and illustrated herein is a preferred embodiment of the invention along with some of its variations. The terms, descriptions and figures used herein are set forth by way of illustration only and are not meant as limitations. Those skilled in the art will recognize that many variations are possible within the spirit and scope of the invention, which is intended to be defined by the following claims—and their equivalents—in which all terms are meant in their broadest reasonable sense unless otherwise indicated.

Claims

1. A system for distributing a cooling fluid in a room containing at least one heat generating component, said system comprising:

a primary heat exchanger having an inlet for receiving the cooling fluid, a heat exchange section configured to facilitate exchange of heat between airflow in the room and the cooling fluid, and an outlet for exhausting heated cooling fluid from the heat exchange section;

a cooling fluid line having a first section and a second section, said first section being connected to the outlet of the primary heat exchanger; and

a secondary heat exchanger having a receiving section connected to the second section of the cooling fluid line for receiving the heated cooling fluid, a heat exchange section configured to facilitate exchange of heat between the at least one heat generating component and the heated cooling fluid from the primary heat exchanger, and an exhaust section configured to exhaust secondarily heated cooling fluid from the secondary heat exchanger.

2. The system according to claim 1, further comprising:

a cooling apparatus for cooling at least one of the heated cooling fluid from the primary heat exchanger and the secondarily heated cooling fluid from the secondary heat exchanger.

3. The system according to claim 1, further comprising:

a plurality of secondary heat exchangers having receiving sections, wherein the cooling fluid line is split into a plurality of sub-lines, each of said plurality of sub-lines being connected to a receiving section of a respective secondary heat exchanger, and wherein the plurality of secondary heat exchangers are arranged in a parallel relationship with respect to each other along the plurality of sub-lines.

4. The system according to claim 1, further comprising:

a plurality of secondary heat exchangers arranged in a serial configuration with respect to each other along the cooling fluid line.

5. The system according to claim 1, wherein the primary heat exchanger comprises one of a floor based and a ceiling based air conditioning unit.

6. The system according to claim 1, wherein the at least one heat generating component is housed in a rack having an inlet for receiving airflow and an outlet for exhausting airflow, and wherein the secondary heat exchanger is configured to be positioned in at least one of the inlet and the outlet of the rack to cool airflow that is one of supplied into and exhausted from the rack.

7. The system according to claim 1, wherein the at least one heat generating component is housed in a rack, and wherein the secondary heat exchanger is configured to be positioned within the rack.

8. The system according to claim 7, wherein the secondary heat exchanger comprises a plurality of heat exchange sections, said plurality of heat exchange sections being configured to be positioned to cool a plurality of heat generating components contained in the rack.

9. The system according to claim 7, wherein the heat exchange section of the secondary heat exchanger comprises at least one cold plate configured to be positioned in thermal contact with the at least one heat generating component.

10. The system according to claim 1, wherein the at least one heat generating component is housed in a rack having an inlet for receiving airflow and an exhaust for exhausting airflow, and wherein the primary heat exchanger is configured to be positioned in the inlet to cool airflow supplied into the rack and wherein the secondary heat exchanger is configured to be positioned within the rack to directly cool the at least one heat generating component housed in the rack.

11. The system according to claim 1, wherein the at least one heat generating component is housed in a rack having an inlet for receiving airflow and an exhaust for exhausting airflow, and wherein the primary heat exchanger is configured to be positioned in the inlet to cool airflow supplied into the rack and wherein the secondary heat exchanger is configured to be positioned in the to exhaust to cool airflow exhausted from the rack.

12. The system according to claim 1, further comprising a tertiary heat exchanger containing a separate cooling fluid, wherein the heat exchange section of the secondary heat exchanger is configured to facilitate heat transfer from the separate cooling fluid contained in the tertiary heat exchanger and the heated cooling fluid.

13. The system according to claim 1, wherein the cooling fluid comprises one of the group consisting of chilled water, R134a, and ethylene glycol mixture.

14. A method of distributing cooling fluid in a room, said method comprising:

supplying a primary heat exchanger with cooled cooling fluid from a cooling apparatus, wherein the primary heat exchanger comprises a heat exchange section that cools airflow supplied into the room thereby causing the cooling fluid to become heated; and

conveying the heated cooling fluid from the primary heat exchanger to a secondary heat exchanger, said secondary heat exchanger being configured to facilitate heat exchange between at least one heat generating component housed in the room and the heated cooling fluid, thereby causing the heated cooling fluid to become secondarily heated.

15. The method according to claim 14, further comprising:

conveying at least one of the heated cooling fluid and the secondarily heated cooling fluid to the cooling apparatus.

16. A data center comprising:

at least one heat generating component;

a cooling fluid distribution system for cooling the at least one heat generating component, said cooling fluid distribution system comprising,

a primary heat exchanger having an inlet for receiving the cooling fluid, a heat exchange section configured to facilitate exchange of heat between airflow in the data center and the cooling fluid, and an outlet for exhausting heated cooling fluid from the heat exchange section;

17. The data center according to claim 16, further comprising:

at least one rack having an inlet for receiving airflow and an exhaust for exhausting airflow, wherein the at least one heat generating component is housed in the at least one rack, and wherein the secondary heat exchanger is positioned on at least one of the inlet and the exhaust of the rack.

18. The data center according to claim 16, further comprising:

at least one rack, wherein the at least one heat generating component is housed in the at least one rack, and wherein the secondary heat exchanger is positioned within the rack and configured to directly cool the at least one heat generating component.

19. The data center according to claim 16, further comprising:

at least one rack having an inlet for receiving airflow and an exhaust for exhausting airflow, wherein the at least one heat generating component is housed in the at least one rack, and wherein the primary heat exchanger is positioned in the inlet to cool airflow supplied into the rack and wherein the secondary heat exchanger is positioned within the rack to directly cool the at least one heat generating component housed in the rack.

20. The data center according to claim 16, further comprising:

at least one rack having an inlet for receiving airflow and an exhaust for exhausting airflow, wherein the at least one heat generating component is housed in the at least one rack, and wherein the primary heat exchanger is positioned in the inlet to cool airflow supplied into the rack and wherein the secondary heat exchanger is positioned in the exhaust to cool airflow exhausted from the rack.