Detailed Description
The following detailed description illustrates a cooling system by way of example and not by way of limitation. Although the following description describes the application of the cooling system for servers installed in a closed environment, the embodiments of the disclosed cooling system may be applied to cooling heat generating components in any application. For example, the presently disclosed embodiments may be used to cool a portable computer when the portable computer is docked to a docking station while running. This description will enable those skilled in the art to make and use the present disclosure for cooling any electronic components in a console or chassis.
Reference will now be made to exemplary embodiments of the invention, as illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. In different figures, elements or portions designated with the same reference numerals perform similar functions. Therefore, for the sake of brevity, these elements are not described with respect to each figure. In the following description, if an element is not described with reference to one drawing, the description of the element with reference to another drawing is equally applicable.
Fig. 2 shows an exemplary single computer server unit (or module 10) having a modular chassis for installation in a server rack. Module 10 includes a motherboard 12 having a plurality of heat-generating electronic devices 14 mounted on motherboard 12 (or connected thereto, for example, using data cables, for example). These electronic devices 14 may include, but are not limited to, any type of IC or other device (e.g., CPU, GPU, memory, power supply, disk drive, controller, etc.) that may be found in a typical computer system.
The module 10 may also include a cooling system 20, the cooling system 20 configured to directly cool one or more electronic devices 14 of the module 10. To directly cool the electronic device 14, the cold plate 26 of the cooling system 10 may be placed in thermally conductive contact with the electronic device 14 (either directly or through a thermally conductive medium, such as a thermally conductive silicone grease or pad). Due to the thermally conductive contact, heat may be conducted from the electronic device 14 to the cold plate 26. The coolant 22 of the cooling system 20 may flow through the cold plate 26 to remove heat and, in turn, cool the electronic device 14. As will be described in more detail below, the conduit 23 may transport the coolant 22 to the cold plate 26, and the conduit 23 may connect the coolant 22 to a suitable heat exchanger. In some embodiments, the cooling system 20 may also include a pump or other liquid moving device (not shown) to assist in transferring the coolant 22 toward and from the cold plate 26. Alternatively, some configurations of the cooling system 20 may not include a pump, but rather rely on expansion and contraction of the coolant 22 as it absorbs and dissipates heat to drive the coolant 22 toward or from the cold plate 26. Any liquid, such as, for example, water, alcohol, a mixture of alcohol and water, etc., may be used as the coolant 22. It will be appreciated that the coolant 22 may comprise a dielectric fluid that is not electrically conductive. The use of a dielectric fluid may prevent damage to the components of the module 10, including the electronic devices 14, if a leak in the cooling system 20 occurs in the module 10. Non-limiting examples of the dielectric fluid include deionized water, mineral oil, and mixtures thereof. These dielectric fluids may also be fluorescent. Although the coolant 22 is described as a liquid, in some embodiments, a phase change material may also be used as the coolant 22. In these embodiments, the liquid form of the coolant 22 may be converted to a gaseous form after the coolant 22 absorbs heat at the cold plate 26. After conducting the heat absorbed from the cold plate 26, the coolant 22 may be converted back to a liquid form. In some embodiments, a valve or other known liquid control device (not shown) may be provided in the cooling system 20 to control the flow of the coolant 22 therein. Any type of cold plate 26 configured to conduct heat from the electronic device 14 to the coolant 22 circulating in the cooling system 20 may be used as the cold plate 26. The cold plate 26 may include fins, pins, or other features to help conduct heat from the cold plate 26 to the coolant 22. In some embodiments, devices for conducting heat from heat-generating electronic equipment to a coolant may be used as the cold plate 26, and such devices in the commonly assigned patent application nos. 10/578,578, 11/919,974, 12/826,736, 12/914,190, and 12/914,263, with appropriate modifications, may be used as the cold plate 26. These patent applications are incorporated herein by reference in their entirety. Although fig. 2 illustrates that the liquid cooling system 20 may directly cool both electronic devices 14, this is merely an example. In general, the cooling system 20 may directly cool any number of the electronic devices 14 of the module 10 via any number of the cold plates 26.
The conduit 23 may exit the module 10 through one or more apertures defined in the chassis of the module 10. In certain embodiments, an empty PCI occlusion shield 30 may be connected to the chassis of the module 10 and may direct the conduit 23 out of the module 10. Hot end 31 of tube 23 may be fluidly connected to one or more fluid connectors 32. More particularly, inlet conduit 33 is configured to direct coolant 22 into module 10 and outlet conduit 34 is configured to direct coolant 22 out of module 10, inlet conduit 33 and outlet conduit 34 may be fluidly connected to fluid connector 32. Fluid connector 32 may be any suitable connection device configured to fluidly connect conduit 23 to other suitable liquid conduits. The fluid connector 32 may also be configured to allow easy connection and disconnection of the conduit 23 to other suitable liquid conduits. Further, the fluid connector 32 may be automatically sealed when connected and/or disconnected with another conduit, and the liquid in the conduit 23 may be prevented from leaking from the connector 32. For example, the fluid connector 32 may include any suitable quick connector, luer lock, or the like.
In a server application, as shown in fig. 3, a plurality of server modules 10 may be mounted on a server rack 50, with the server rack 50 being positioned in a server room 100. The cabinet 50 may in turn be connected to a manifold 60. Manifold 60 may include any suitable enclosure configured to enclose a number of liquid conduits and components, and may introduce liquid to various components inside and/or outside manifold 60. Further, the manifold 60 may be configured to mount on any suitable server rack 50. On the server side of the manifold 60, the manifold 60 may be fluidly connected to the module 10, and on the heat exchanger side of the manifold 60, the manifold may be fluidly connected to the secondary cooling system 42. The coolant 22 of the cooling system 20 may be introduced into the manifold 60, cooled by the secondary cooling system 42, and returned into the module 10 for removing heat from the electronic device 14.
As above, the module 10 may be fluidly connected to the manifold 60. More particularly, the conduit 23 may be fluidly connected to the manifold 60 by a fluid connector 32. In other words, the fluid connector 32 may fluidly connect the inlet conduit 33 of each cooling system 20 to an outlet line 61 housed in the manifold 60, and may fluidly connect the outlet conduit 34 of each cooling system 20 to an inlet line 62 housed in the manifold 60. In certain embodiments, the elongated enclosure 200 may be connected to the server rack 50 and may house the inlet and outlet ducts 33, 34 of the cooling system 20. The fluid connector 32 may be mounted on the exterior of the elongate housing 200 and may be fluidly connected to an outlet line 61 or an inlet line 62 internal or external to the manifold 60. In other embodiments, the elongated housing 200 may be eliminated and the manifold 60 may be mounted directly to the server rack 50.
An inlet line 62 enclosed in the manifold 60 may transport the coolant 22 of the cooling system 20 to the one or more platens 18, and the coolant 22 is thereby cooled. The relatively cool coolant 22 may then flow out of the one or more hot plates 18 and back to the cold plates 26 to absorb heat generated by the electronic device 14 via an outlet line 61 enclosed in the manifold 60 and the inlet conduit 33 of the cooling system 20. The platens 18 may be encapsulated into the manifold 60 and may include any suitable components configured to provide heat transfer between the coolant and the heat exchanging surfaces. For example, the thermal plate 18 may include one or more of the features of the thermal plate and cold plate disclosed in patent application No. 13/215,384, which is incorporated herein by reference in its entirety.
Coolant 22 may be cooled by extracting heat from one or more platens 18 via a secondary cooling system 42. As shown in fig. 3, the secondary cooling system 42 may have a heat conducting medium 43 circulated therein to absorb heat from the cooling systems 20 associated with the different modules 10 and release the heat removed from these modules 10. Any type of liquid, such as water, alcohol, mixtures thereof, gas, and the like, may be used as the heat transfer medium 43. It is also contemplated that in some embodiments, a phase change material may be used as the heat transfer medium 43. In some embodiments, the secondary cooling system 42 may be a closed loop cooling system. However, it is contemplated that in other embodiments, the secondary cooling system 42 may be an open loop system.
As shown in fig. 3, secondary cooling system 42 may absorb heat from one or more modules 10 disposed in server room 100 and release the heat outside of server room 100. The secondary cooling system 42 may include one or more cold plate elements 41, a cooling device 40 disposed outside the server room 100, and a conduit for conducting a thermally conductive medium 43 between the cooling device 40 and the one or more cold plate elements 41. The one or more cold plate elements 41 may include any suitable components configured to provide thermal conduction between the coolant and the heat exchange surface. For example, one or more of the cold plate elements 41 may include the features of one or more of the hot plates and cold plates disclosed in the commonly assigned patent application No. 13/215,384. The cooling device 40 may include any suitable device configured to remove heat from the heat transfer medium 43 flowing therethrough, such as a liquid-to-gas heat exchanger. At least a portion of the conduits of the one or more cold plate elements 41 and the secondary cooling system 42 may also be enclosed into the manifold 60, and the one or more cold plate elements 41 may be placed in thermal contact (either directly or through a thermally conductive medium 45, such as a thermally conductive silicone or pad) with the one or more hot plates 18 of the cooling system 20. Because of the thermal contact, heat may be conducted from the one or more hot plates 18 to the one or more cold plate elements 41. The heat transfer medium 43 may be circulated between the cooling device 40 and the one or more cold plate elements 41 such that the heat transfer medium 43 may absorb heat from the one or more hot plates 18 of the module 10 and release the heat outside of the server room 100. In some embodiments, a pump and/or other control device may be used to help direct the heat transfer medium 43 through the secondary cooling system 42. The heat generated by the servers is transmitted to the outside, so that heating of the air in the server room 100 can be avoided, and the cooling load of the cooling system of the server room 100 can be reduced. It is also contemplated that the heat removed from the server room by the heat transfer medium 43 may be used for useful work. For example, the removed heat may be used in an HVAC system to provide heat to a building.
It should be appreciated that secondary cooling system 42 may provide heat transfer in an inactive manner. In other words, the secondary cooling system 42 does not require an energy or power source to actively remove heat from the module 10. Alternatively, for example, the cooling device 40 may be installed outside the server room 100, and may cool the heat transfer medium 43 of the secondary cooling system 42 by contact with the ambient air. The ambient air may be, for example, air outside a building in which the server room 100 is installed, or air inside the building but outside the server room 100. Since no additional energy is required to cool the heat transfer medium 43, cost savings and energy savings can be achieved. It should also be understood that one or more fans or other ventilation devices may be connected to the cooling device 40 to direct more ambient air onto the cooling device and increase cooling of the heat transfer medium 43 with minimal energy consumption. Further, only the electronics 14 of the module 10 may be cooled by the disclosed cooling system, and the electronics 14 may include a CPU, GPU, memory, and the like. These electronic devices 14 can generate the most heat in the module 10 because they consume the most power; however, at relatively high temperatures, the electronic device 14 is still capable of operating. Thus, the ambient air is sufficient to cool the device 14 to a suitable operating temperature while removing most of the heat generated in the module 10.
In certain embodiments, a fluid connector 70, similar to the fluid connector 32, may be connected to the manifold 60 to fluidly connect one or more cold plate elements 41 enclosed within the manifold 60 to a cooling device 40 external to the server room 100. In other words, the conduits of the secondary cooling system 42 that provide fluid communication between the one or more cold plate elements 41 and the cooling device 40 may be easily attached and detached via the fluid connectors 70. Thus, the fluid connectors 70, along with the fluid connectors 32, may enable the modules 10, the manifold 60, and the cooling device 40 to be easily separated from one another for purposes such as repair and maintenance. It should be understood that the fluid connector 70 may be disposed within the housing of the manifold 60 or may be disposed outside the housing of the manifold 60 housing. In addition, because the fluid connectors 32, 70 may be automatically sealed, mess and clean up due to fluid leaks may be reduced. In addition, the fluid connectors 32, 70 and the manifold 60 may also provide for quick and easy installation of the module 10 to the cooling device 40 for heat dissipation.
Fluid connectors 32 may also provide the ability to easily connect and disconnect individual modules 10 to and from manifold 60 and, thereby, selectively control the cooling of one or more modules 10 mounted on server rack 50. For example, if one or more modules 10 require maintenance and/or repair, those modules 10 may be selectively separated from the manifold 60, while the remaining modules 10 may be operatively connected to the manifold 60 and have their respective electronics 14 cooled.
Further, it should be understood that the fluid connectors 32, 70 and the manifold 60 may provide a modular mechanism for cooling the module 10. In certain embodiments, the fluid connectors 70 may instead be fluidly connected to existing plumbing (not shown), and may in turn direct the cooled coolant to one or more of the cold plate elements 41. In other words, the manifold 60 may allow the modules 10 to change the manner in which they are cooled. For example, a technician may disconnect the fluid connector 70 from the cooling device 40 shown in fig. 3 and reconnect the fluid connector 70 with the existing utility lines as an alternative source for cooling.
Further, the configuration of manifold 60, fluid connectors 32, and fluid connectors 70 may provide two separate cooling loops: a cooling loop associated with cooling system 20, and a cooling loop associated with secondary cooling system 42. Separating the loops of the cooling system 20 and the secondary cooling system 42 may facilitate maintenance and repair of the servers. For example, if a coolant leak (e.g., a leak associated with cooling system 20) is detected in the server, heat transfer medium 43 need not be removed and/or refilled only if coolant 22 needs to be removed and refilled to repair the leak, because cooling system 20 and secondary cooling system 42 are separate. Thus, the amount of coolant that eventually needs to be discarded and reloaded can be minimized, thereby reducing maintenance and repair costs. Further, it should be understood that because the fluid connectors 32, 70 may be self-sealing, the manifold 60 may be manufactured and distributed with the coolant 22 and the heat transfer medium 43 pre-filled in appropriate conduits of the manifold 60.
It should be understood that in certain embodiments, the secondary cooling system 42 may be eliminated and at least a portion of the manifold 60 enclosing the one or more thermal plates 18 may be placed outside of the server room 100 to draw heat away from the coolant 22.
Fig. 4 illustrates another embodiment of a server application, wherein a server room 100 comprises a plurality of server racks 50 on which modules 10 are mounted. In certain embodiments, referring to FIG. 3, each server rack 50 may be connected to its own dedicated cooling device 40. The separate cooling devices 40 may provide enhanced cooling for modules mounted on each server rack 50 and may also simplify maintenance and repair work when each server rack 50 may be separately connected, e.g., one or more cooling devices 40 are to be inspected and repaired. However, it should be understood that each server cabinet 50 may be connected to a separate cooling device 40, as shown in fig. 4. Using a separate cooling device 40 may reduce the amount of material and components used to cool the module 10 and may minimize the amount of space occupied by the cooling device 40.
In certain embodiments, it should be understood that one or more secondary manifolds may be fluidly connected to the server racks 50 and the manifold 60. In these embodiments, for example, any number of sub-racks may be mounted to the server rack 50. Each sub-enclosure may include a plurality of server modules, blade servers, or similar devices connected together and mounted to the sub-enclosure. In a similar manner as discussed above in the embodiments of fig. 2-4, a secondary manifold may be fluidly connected to each sub-cabinet. A coolant, such as coolant 22, may be directed from the manifold 60 to each module of the sub-rack to cool one or more electronic devices, such as electronic device 14. Coolant from each module may be conducted through a secondary manifold, and separate lines of the secondary manifold may direct the coolant into the manifold 60 for cooling. The coolant may be cooled and returned to each module of the sub-rack.
Because the disclosed server cooling system may allow the modules 10 of the servers to be cooled without conducting heat to the server room 100, the necessity of employing a large CRAC system is eliminated. Furthermore, because ambient air may be used to remove heat from the cooling device 40, the cooling device 40 of the secondary cooling system 42 consumes zero to minimal power. Eliminating the need to employ large CRAC systems to cool the server room 100 and the use of ambient air to remove heat from the modules greatly reduces the power consumption associated with cooling the servers. The reduction in power consumption results in more efficient use and conservation of available energy, and is accompanied by a reduction in greenhouse gas emissions.
Various modifications and variations to the disclosed cooling system will be apparent to those skilled in the art. Other embodiments will be apparent to those skilled in the art from consideration of the specification and practice of the disclosed cooling system. It is intended that the specification and examples be considered as exemplary only, with a true scope being indicated by the following claims and their equivalents.