Abstract:
An exemplary method may comprise thermally coupling a network of cooling lines to each of a plurality of heat exchangers in a cooling system. The method may also comprise providing a first connection from a network of cooling lines to a first fluid source and a second connection from the network of cooling lines to a second fluid source for configuring the network of cooling lines in different states. The method may also comprise delivering cooling fluid through the network of cooling lines to each of the plurality of heat exchangers both when the network of cooling lines is connected only to the first fluid source and when the network of cooling lines is connected to both the first and second fluid sources.

Description:
PRIORITY CLAIM 
       [0001]    This application claims priority to co-owned U.S. Provisional Patent Application No. 60/796,259 for “Flexible Redundant Cooling For Computer Systems” of Belady, et al., filed Apr. 28, 2006, and is a continuation/divisional of co-owned U.S. patent application Ser. No. 11/673,410 for “Cooling Systems and Methods” of Belady, et al., filed Feb. 9, 2007 and claiming priority to the &#39;259 provisional patent application, each hereby incorporated by reference in its entirety as though fully set forth herein. 
     
    
     BACKGROUND 
       [0002]    Electronic data centers including multiple computer systems (e.g., rack-mounted servers) and other electronic devices are becoming more densely packed to provide more computing power while at the same time consuming less physical space. Accordingly, heat dissipation continues to be a concern. If not properly dissipated, heat generated during operation can shorten the life span of various components and/or generally result in poor performance. 
         [0003]    Various thermal management systems are available for computer systems and other electronic devices, and typically include a heat sink and/or a cooling fan. The heat sink is positioned adjacent the electronic components generating the most heat (e.g., the processor) to absorb heat. A cooling fan may be positioned to blow air across the heat sink and out an opening formed through the computer housing to dissipate heat into the surrounding environment. The use of water-cooled systems is also being explored. However, if the heat sink, cooling fan, and/or water supply fails or is otherwise taken offline (e.g., for maintenance purposes), one or more of the computer systems and/or other electronic devices may need to be taken offline as well to prevent overheating until the cooling system can be returned to an operational state. Any such shutdown, even a partial shutdown, can have a far reaching negative impact and therefore is considered undesirable. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0004]      FIGS. 1   a  and  1   b  are top and side views, respectively, of an exemplary cooling system as it may be implemented in a rack-mount environment for server computers. 
           [0005]      FIGS. 2-4  are simplified views of exemplary embodiments of the cooling system showing primarily the network of cooling lines. 
           [0006]      FIGS. 5 and 6  show alternative embodiments of a cooling system. 
       
    
    
     DETAILED DESCRIPTION 
       [0007]    Briefly, cooling systems and methods may be implemented to dissipate heat during operation of various computing and electronic devices, such as in the rack-mount environment commonly used by electronic data centers. In an exemplary embodiment, the cooling systems and methods include redundant fluid sources for cooling operations. Optionally, the cooling system may be configured for use with either single or multiple fluid sources. Where multiple fluid sources are used, if one of the fluid sources fails, is taken offline, or is otherwise unavailable, an alternate fluid source may continue to provide sufficient cooling to prevent a partial or even complete shut down of the computing and/or other electronic devices. 
         [0008]      FIGS. 1   a  and  1   b  are top and left-side views, respectively, of an exemplary cooling system  100  as it may be implemented in a rack-mount environment for server computers. Directional notations  105   a  and  105   b  are shown in  FIGS. 1   a  and  1   b,  respectively, to help orient the reader. 
         [0009]    Before continuing, it is noted that the rack-mount environment in  FIGS. 1   a  and  1   b  is shown only for purposes of illustration. The systems and methods described herein are not limited to use with any particular physical environment. Nor are the systems and methods limited to use with any particular type of computers or other electronic devices. 
         [0010]    In an exemplary embodiment, a rack-mount  110  may be implemented to arrange a plurality of computer systems (e.g., server computer  120  mounted to physical structure or rack  109 ) and/or other electronic devices such as storage, communications, and/or data processing devices (not shown). The rack-mount  110  may include an outer enclosure  130  with access door  135 . The server computers are typically arranged within the enclosure  130  in a stacked relation relative to one another. Accordingly, only one server computer  120  is visible from the top view shown in  FIG. 1   a.  Of course, a wide variety of other types of rack-mounts are also commercially available. For example, larger rack-mounts enable the server computers to be arranged in a stacked relation and a side-by-side relation relative to one another. 
         [0011]    Each server computer  120  may include one or more processing units or processors, data storage, and/or memory. Each server computer  120  may also be operatively associated with other electronic components, such as, communication and networking devices (routers, switches, hubs), and a wide variety of input/output (I/O) devices. These other electronic components may also be arranged in the rack-mount  110 . 
         [0012]    During operation, the server computers and other electronic components may generate heat. Accordingly, a cooling system  100  may be implemented to absorb and remove heat from the rack-mount  110 . In an exemplary embodiment, the cooling system  100  includes one or more heat exchangers  140   a - d  located near or adjacent the components generating the heat. The heat exchangers  140   a - d  function to absorb heat generated by the various heat-generating components. 
         [0013]    In an exemplary embodiment, the heat exchangers  140   a - d  are made of a thermally conductive material (e.g., metal or metal alloys, composites, ceramic, plastics, etc.) for quickly and efficiently absorbing heat from the surroundings and releasing it to a second medium (e.g., a fluid medium such as water) flowing through the heat exchangers  140   a - d.  It is noted that there exist many different types of heat exchangers, and the systems and methods described herein are not limited to any particular type of heat exchangers  140   a - d.  Optionally, the cooling system  100  may also include one or more cooling fans  160   a - d  arranged to move or circulate air in a closed loop between the server computer  120  and heat exchangers  140   a - d  through ducting  150   a - d  and out vent  170   a - d  in the direction generally illustrated by arrows  101 - 103 . 
         [0014]    It is noted that although four heat exchangers  140   a - d  and cooling fans  160   a - d  are shown in  FIG. 1   b,  any number may be implemented. Indeed, there need not be a one-to-one correlation of heat exchangers to cooling fans. It is also noted that the location of the components may also vary (e.g., on the side next to the server computer  120  as shown, bottom, front, rear, or top). The specific implementation may depend on any of a wide variety of different design considerations, such as, the heat being generated, the desired cooling, and the surrounding environment, to name only a few examples. 
         [0015]    As mentioned above, a cooling fluid (e.g., water) may be circulated through the heat exchangers  140   a - d  to remove heat. The cooling fluid may be connected to one or more fluid source  180  (e.g., a building&#39;s water supply), and provided to the heat exchangers  140   a - d  via a network of cooling lines  190 . In an exemplary embodiment, the network of cooling lines  190  may be configured (or reconfigured) for use with either single or multiple fluid sources. Such an implementation enables a production and distribution of a single cooling system  100  which can be used in more than one environment, thereby reducing costs. 
         [0016]    In addition, the cooling system  100  may be operated in a redundant mode if it is configured for use with multiple fluid sources. That is, if one of the fluid sources fails, is taken offline, or otherwise is unavailable, an alternate fluid source may continue to provide sufficient cooling to continue operations (e.g., of one or more server  120 ). 
         [0017]    In an exemplary embodiment, power consumption may also be automatically reduced in the event that one or more of the fluid sources is unavailable. That is, operation of the heat-generating components is constrained by the ability of the cooling system  100  to dissipate heat. In some circumstances, at least some of the components (e.g., critical servers) may continue to operate at full power while power to other components (e.g., to alternate, backup systems, or those executing low priority applications that are not business critical) is reduced or even turned off to meet these constraints. In any event, the loss of a fluid source for cooling operations does not result in a complete shut down. 
         [0018]    It is noted that any of a wide variety of configurations of the cooling system  100  may be implemented to accomplish these and other advantages. Some examples of different configurations are discussed below with reference to  FIGS. 2-6 . 
         [0019]      FIGS. 2-4  are simplified views of exemplary embodiments of the cooling system showing primarily the network of cooling lines (e.g., the network of cooling lines  190  shown in  FIG. 1   b ). Other system components have been omitted or simplified in  FIGS. 2-4  to better show different configurations of the network of cooling lines, 
         [0020]      FIG. 2  shows two configurations  200  and  200 ′ of a network of cooling lines  290  that may be implemented in the same cooling system (e.g., cooling system  100  shown in  FIGS. 1   a  and  1   b ). The network of cooling lines  290  may be connected to a single fluid source  280 , as shown in the first configuration  200 . The network of cooling lines  290  may also be connected to dual fluid sources  280  and  281 , as shown in the second configuration  200 ′. 
         [0021]    In the first configuration  200 , the network of cooling lines  290  is connected to a first fluid source  280  such that a cooling fluid may circulate via fluid lines  291   a - d  (delivery lines) and fluid lines  292   a - d  (return lines). The fluid lines  291   a - d  and  292   a - d  are interconnected by junction boxes  295   a - d.  Junction boxes  295   a - d  also serve to connect the fluid lines to the heat exchangers (e.g., as can be seen in  FIG. 1   b ). Other embodiments are also contemplated wherein substitutions are made for the junction boxes. 
         [0022]    The same cooling system may be configured (as illustrated by arrow  201 ) in the second configuration  200 ′ by removing the fluid lines  291   c  (delivery line) and  292   c  (return line) between junction boxes  295   b  and  295   c,  and adding fluid line  291   e  (delivery line) and fluid line  292   e  (return line) between the second fluid source  281  and junction box  295   d.    
         [0023]    In the second configuration  200 ′, the cooling system is redundant. That is, if one of the fluid sources  280  or  281  is unavailable, operations may continue with each heat exchanger carrying a portion of the load. For purposes of illustration, the cooling system may be configured for operation at full power when fluid is provided by both fluid sources  280  and  281 . But if one of the fluid sources  280  or  281  is unavailable, the operations need only be reduced by 50% because each heat exchanger is still able to dissipate 25% of the heat being generated where four heat exchanger are used. Other embodiments are also contemplated, e.g., sized for 200% capacity so that when one line fails, 100% of the load is still maintained. 
         [0024]      FIG. 3  shows two configurations  300  and  300 ′ of a network of cooling lines  390  that may be implemented in the same cooling system (e.g., cooling system  100  shown in  FIGS. 1   a  and  1   b ). The network of cooling lines  390  may be connected to a single fluid source  380 , as shown in the first configuration  300 . The network of cooling lines  390  may also be connected to dual fluid sources  380  and  381 , as shown in the second configuration  300 ′. 
         [0025]    In the first configuration  300 , the network of cooling lines  390  is connected to a first fluid source  380  such that a cooling fluid may circulate via fluid lines  391   a - d  (delivery lines) and fluid lines  392   a - d  (return lines). The fluid lines  391   a - d  and  392   a - d  are interconnected by junction boxes  395   a - d.  Junction boxes  395   a - d  also serve to connect the fluid lines to the heat exchangers (e.g., as can be seen in  FIG. 1   b ). 
         [0026]    In addition, control valves  398   a  and  398   b  may be provided on fluid lines  391   c  and  392   c,  respectively. These may be open when the network of cooling lines  390  is connected to only the first fluid source  380 . The same cooling system may be configured (as illustrated by arrow  301 ) in the second configuration  300 ′ by closing these valves (the closed valves are designated  398   a ′ and  398   b ′), and adding fluid line  391   e  (delivery line) and fluid line  392   e  (return line) between the second fluid source  281  and junction box  295   d.  Accordingly, the fluid lines  391   c  (delivery line) and  392   c  (return line) do not need to be removed to configure the network of cooling lines  390  in the second configuration  300 ′. Again, the cooling system is redundant in the second configuration  300 ′, and there is only need for a single part number where a valve is used to set the configuration during installation at the customer site. 
         [0027]      FIG. 4  shows two configurations  400  and  400 ′ of a network of cooling lines  490  that may be implemented in the same cooling system (e.g., cooling system  100  shown in  FIGS. 1   a  and  1   b ). The network of cooling lines  490  may be connected to a single fluid source  480 , as shown in the first configuration  400 . The network of cooling lines  490  may also be connected to dual fluid sources  480  and  481 , as shown in the second configuration  400 ′. 
         [0028]    In the first configuration  400 , the network of cooling lines  490  is connected to a first fluid source  480  such that a cooling fluid may circulate via fluid lines  491   a - d  (delivery lines) and fluid lines  492   a - d  (return lines). The fluid lines  491   a - d  and  492   a - d  are interconnected by junction boxes  495   a - d.  Junction boxes  495   a - d  also serve to connect the fluid lines to the heat exchangers (e.g., as can be seen in  FIG. 1   b ). 
         [0029]    Control valves  498   a - f  may be operated to configure the network of cooling lines  490  in the first configuration  400  by opening control valves  498   a - d  and closing control valves  498   e  and  498   f.  Control valves  498   c - d  and  498   e - f  may be opened and control valves  498   a - b  closed to configure the cooling system in a second configuration  400 ′ for connection to dual fluid source  480  and  481 . Again, the cooling system is redundant in the second configuration  400 ′. 
         [0030]    Also when the network of cooling lines  490  is in the second configuration  400 ′, the control valves may be operated to reconfigure the network of cooling lines  490  for a single fluid source in the event one of the fluid sources  480  or  481  becomes unavailable during operation. In addition, if fluid source  481  is lost for example, the system senses this and shuts control valves  498   e - f  and dynamically opens control valves  498   a - b  so that so that no capacity is lost during operation and it is all done automatically (e.g., the system is self aware as to whether there is one source or two so that it auto configures at installation, or auto reconfigures due to a failure). 
         [0031]      FIGS. 5 and 6  show alternative embodiments of a cooling system. It is noted that 500- and 600-series reference numbers are used in  FIGS. 5 and 6  to refer to corresponding elements of the embodiment of cooling system  100  shown in  FIG. 1   b,  and may not be described again with reference to the different embodiments of cooling systems shown in  FIGS. 5 and 6 . 
         [0032]      FIG. 5  shows two configurations  500  and  500 ′of the same cooling system. In the first configuration, the cooling system includes a single heat exchanger  540 , at least one cooling fan (four cooling fans  560   a - d  are shown), and ducting  550 . The cooling system can be configured for in a second configuration  500 ′ for dual fluid sources  580  and  581  by adding another heat exchanger  540 ′. 
         [0033]    In an exemplary embodiment, the heat exchangers  540  and  540 ′ are configured in series with all of the cooling fans  560   a - d.  Such a configuration reduces the likelihood of a failure that cripples the entire system. In addition, the system is modular and may be upgraded in the field to make it redundant for customers who may change their cooling configuration to redundant sources. Furthermore, the system can be easily configured in the factory or can be configured during installation by adding heat exchanger. 
         [0034]      FIG. 6  shows two configurations  600  and  600 ′of the same cooling system. Configurations  600  and  600 ′ are similar to the configurations shown in  FIG. 5 . In this embodiment, however, the cooling system is provided with optional jumper lines  699  between the heat exchangers  640  and  640 ′. Accordingly, the same system can be configured without having to obtain a heat exchanger  640 ′ (e.g., after purchasing the cooling system). 
         [0035]    It is noted that control valves (e.g., as shown in  FIGS. 3 and 4 ) may also be implemented in the embodiments shown in  FIG. 6 . For example, static control valves, such as those shown in  FIG. 3 , may be implemented to open or close depending on the configuration  600  or  600 ′. In addition, dynamic control valves, such as the servo controlled valves shown in  FIG. 4 , may be implemented on lines  699  and  690  (for  680  and  681 ). In this way the system may be automatically configured as a function of the conditions sensed during installation or failure. 
         [0036]    It should be appreciated that various exemplary embodiments of the cooling system shown (and other embodiments not shown) may be manufactured and shipped for configuration as either a single or a dual fluid cooled system at the factory, and then configured at the customer site. When the cooling system is configured for dual sources, it also has redundant cooling capacity. 
         [0037]    It is noted that the exemplary embodiments discussed above are provided for purposes of illustration. Still other embodiments are also contemplated. For example, fluid line failures may be detected automatically by the building monitoring system and/or with sensors (e.g., pressure, flow, temperature sensors) included as part of the cooling system itself, and/or control valves may be automatically opened/closed to support the building fluid supply conditions. 
         [0038]    It is also noted that, although the systems and methods are described with reference to computer systems, in other exemplary embodiments, the cooling systems may be implemented for other electronic devices, such as, e.g., peripheral devices for computers, video and audio equipment, etc. 
         [0039]    In addition to the specific embodiments explicitly set forth herein, other aspects and embodiments will be apparent to those skilled in the art from consideration of the specification disclosed herein. It is intended that the specification and illustrated embodiments be considered as examples only.