Abstract:
A cooling apparatus for a container-based data center comprises an air handling housing, at least one movable louver, a filter and a fan. The housing is configured for suspending from a ceiling of the container and comprises at least one heat exchanger. The louver is movable to direct air flow along different paths within the housing according to a selected operating mode. The fan is positioned in the housing and controllable according to the selected operating mode. The heat exchanger is configured in a self-contained water chilling circuit positioned within the container for use in a closed loop mode. The apparatus is convertible for use in an economizer mode that draws outside air into the container. An optional auxiliary heat exchanger element has a cold side heat exchange portion positioned outside the container and a connection through the ceiling to a hot side heat exchange portion positioned within the housing.

Description:
BACKGROUND 
       [0001]    Container-based data centers present difficult environmental management challenges. As the containers are intended to be movable, they have relatively fixed dimensions and cannot be expanded in size. Customers continue to demand more computing power from each container-based data center, so planned products specify only minimal spacing between servers and related equipment and the surrounding container. As a result of increasing the number, capacity and/or computing power of the servers, the heat load generated during their operation increases. This heat load must be managed to promote high performance and long life of the servers. 
         [0002]    In addition, the cooling system for a container-based data center should be adaptable to suit a range of different requirements. For example, the cooling system should be adaptable to provide sufficient cooling in different geographical areas, as well as over different seasons and different times of day. As customer needs change, the container may be fitted with a fewer number or greater number of servers, which may affect the heat load. Other types of equipment changes or technology advances may also affect the heat load and consequently, the required cooling capacity. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0003]      FIG. 1  is a schematic perspective view of a cooling apparatus for a container-based data center showing its ability to be adapted among at least the three illustrated operating modes. 
           [0004]      FIG. 2  is an end view of a container-based data center showing an implementation of the cooling apparatus adapted for a closed loop operating mode. 
           [0005]      FIG. 3  is an end view of a container-based data center showing an implementation of the cooling apparatus adapted for an open loop operating mode. 
           [0006]      FIG. 4  is an end view of a container-based data center showing an implementation of the cooling apparatus adapted for use in an auxiliary cooling mode with an auxiliary heat exchanger. 
           [0007]      FIG. 5A  is a perspective view of an embodiment of the cooling apparatus housing. 
           [0008]      FIG. 5B  is a side section view in elevation of the cooling apparatus housing of  FIG. 5A , but showing the louver in an opened position and the air flow path down through a filter and laterally through the fan and out an outlet. 
           [0009]      FIG. 5C  is a perspective view similar to  5 A, except showing the filter being removed for servicing or replacement. 
           [0010]      FIG. 6A  is an end elevation view of a cooling apparatus according to another implementation with the housing material removed to reveal the internal components and their configuration. 
           [0011]      FIG. 6B  is a top plan view of the cooling apparatus of  FIG. 6A . 
           [0012]      FIG. 6C  is a right side elevation view of the cooling apparatus of  FIGS. 6A and 6B . 
       
    
    
     DETAILED DESCRIPTION 
       [0013]    Described below are implementations of a cooling system for a container-based data center that is adaptable to operate in different modes and has a ceiling-mounted housing configured to fit in a space above existing server racks and other equipment. Within the housing, a fan or other type of air mover draws air through a cooling unit, which generally includes a heat exchanger. In some implementations, this heat exchanger is configured to be part of a self-contained chilled water cooling circuit within the container. The cooling system can be operated in a closed loop mode using this heat exchanger to cool the air within the container. The cooling system can also be adapted between the closed loop mode and other operating modes, such as an open loop mode that draws in outside air and an auxiliary cooling mode that uses an auxiliary heat exchanger having its cold side heat exchanger portion mounted outside the container. These and other implementations are described below in greater detail. 
         [0014]      FIG. 1  is a perspective view showing a schematic depiction of a container-based data center  100  with a multi-mode cooling system  102  adaptable to operate in at least the three illustrated modes  104 ,  106 ,  108 . A representative container or container structure  112  defines a footprint and serves to house multiple server racks  114  and other equipment. As shown, the server racks  114  in this implementation are generally vertically oriented and arranged approximately along a center longitudinal axis of the container  112 , although many other configurations are possible. 
         [0015]    A housing  116  for the cooling system or apparatus  102  is configured to occupy a space above the server racks  114  and below a ceiling  118  of the container. In some implementations, the housing  116  is mounted to or suspended from the ceiling  118 . In this way, the housing  116  does not consume valuable floor space or footprint, which is reserved for servers, other equipment and ensuring that personnel can gain access to and maintain servers and equipment. 
         [0016]    In addition to its ceiling  118 , the container  112  has side walls  120 ,  122 , end walls  124 ,  126  and a floor  128  that together define an interior  130  as shown. In some implementations, the container  112  has dimensions consistent with a shipping container, such as, e.g., an ISO C container, although the cooling system  102  could of course be used with container-based or similar systems of different sizes. 
         [0017]    The cooling apparatus  102  and its housing  116  will be described in more detail in connection with  FIG. 1  and  FIGS. 2-4 , which are separate end elevation views of the data center  100  with the end wall  124  removed to show the three different operating modes. The housing  116 , which is shown in solid lines in  FIG. 1 , generally extends along a majority of the length of the container  112 . An inlet opening  132  is defined in the housing  116  at or near a first end  134  (see, e.g.,  FIG. 2 ). In the illustrated implementation, the inlet opening  132  is formed in an angled surface of the housing  116  (see also, e.g.,  FIGS. 5A-5C ). 
         [0018]    Within the housing, there is a cooling unit  136  for cooling air. In some implementations, the cooling unit  136  includes a heat exchanger  137  having an air “hot side” for receiving hot air drawn in through the inlet opening  132  and cooling it, and a cooling fluid “cold side” for receiving heat from the hot air and dissipating it. In some implementations, the cooling fluid is chilled water, and the heat exchanger (also referred to herein as “a chilled water cooler”) is connected in series to other components of a conventional chilled water loop, including other heat exchanger(s), a pump, valves, sensors and other components. In some implementations, the chilled water system is described as a stand-alone 60-ton chilled water system. In other implementations, the heat exchanger  137  could be a refrigerant-based heat exchanger that uses R-134a or a similar refrigerant. Other types of heat exchangers can also be used. 
         [0019]    There is a fan  138  or other type or air mover for moving air through the housing  116  and throughout the rest of the various air flow circuits as shown by the arrows. In the illustrated implementation, the fan  138  draws air into the housing  116  and conveys it out through an outlet opening  146  positioned at or near a second end  148  of the housing  116  into the interior  130  of the container  112 . A louver  140  or other air directing device is positioned between the fan  138  and the outlet opening  146  on one side, and the inlet opening  132  and the cooling unit  136  on the other side, to selectively adapt the flow path according to the desired operating mode. Referring to  FIGS. 2-4 , the louver  140  in some implementations has blades two  142 ,  144 , although it would be possible to use a single blade or more than two blades. For example, in  FIG. 1 , the louver has three blades. Further details about the flow path are described below. 
         [0020]    The outlet opening  146  can be designed as a specific opening, or it can includes spaces in and around the fan  138  and its mounting and enclosure. For example, as shown in  FIG. 5A , there can be a grille or grate  147  positioned in the area of the outlet opening. 
         [0021]    As best seen in  FIG. 2 , the multi-mode cooling apparatus  102  and housing  116  can be designed to have a vertical dimension V designed to closely fit the space between an upper surface of a tallest server rack (or other piece of equipment) and the ceiling  118  of the container. In some implementations, such as is shown in  FIG. 2 , a bottom surface  150  of the housing  112  is fitted very close to the server racks  114  such that only a small gap G between the two exists. The gap can be filled with a seal S to promote flow in the direction of the arrows as shown, which includes flow into and through the server racks  114 , e.g., from right to left as shown in the figures without substantial air flow “short circuiting” through the gap G. The airflow in the area of the racks  114  may be supplemented by specific rack or server cooling systems (not shown). 
         [0022]    Referring to the upper left view in  FIG. 1  and  FIG. 2 , the multi-mode cooling apparatus is shown configured for a closed loop operating mode  104 . In the closed loop operating mode, hot air from the interior  130  is drawn through the inlet opening  132  and cooling unit  136  and through the louver  140  (in an open position as shown) under the action of the fan  138 . During the process, the cooling unit  136  cools the hot air, such as by heat transfer to chilled water circulating in the heat exchanger  137  of the cooling unit. The cooled air is then exhausted from the housing through the outlet opening  146  and back into the interior  130 . The air flow cycle is completed by the air flowing through the server racks  114  from right to left as shown by the arrows. 
         [0023]    Referring to the upper right view in  FIG. 1  and  FIG. 3 , the multi-mode cooling apparatus is shown configured for an open loop cooling mode  106 . In the open loop cooling mode, cooling the hot air in the interior  130  includes adding other air, e.g., air at a lower temperature. In some implementations, the air that is added is outside air, such as when outside air temperatures are favorable or other circumstances warrant using outside air. 
         [0024]    To admit outside air, there can be at least one opening  164  ( FIG. 3 ) formed in the housing  116  and/or roof of the container  162 . In most cases, it is desirable to provide filtration, which as used herein broadly means preventing airborne matter (particles, precipitation, objects, etc.), as well as preventing other undesired objects (animals, trespassers, etc.) from entering the container through the opening  164 . Therefore, one or more filtering elements (shown schematically at  174 ) is typically provided, in addition to simply forming the opening in the container. Conveniently, the filtering element  174  can be provided in a separate housing called an outside air module  160 . The outside air module  160  is designed to be installed on the roof of the container  112 . Referring to  FIG. 3 , the outside air module  160  can include a duct  169  or other air directing member, such as to guide air from a side opening to an opening  172  (as is described below in greater detail). 
         [0025]    Referring to  FIG. 1 , in some implementations, there are first and second openings  166 ,  168  formed in the housing  116 /roof  162  and aligned first and second openings  170 ,  172  formed in the outside air module  160 . In this way, better circulation through the outside air module  160  can be achieved. In the illustrated implementation, the louver  140  is changed to the closed position for the open loop operating mode, which causes hot air to be drawn from the interior  130 , through the cooling unit  136 , through the openings  166 ,  170  and into the outside air module  160 , through the module  160  to mix with cooler outside air, and back through the openings  172 ,  168  into the housing  112  and out through the outlet opening  146  as cooler air. 
         [0026]    The cooling unit  136  can be operated normally during the open loop mode, in which case the addition of cooler outside air serves as redundant cooling to supplement the cooling it normally provides. Alternatively, the cooling unit  136  need not be operated, such that only outside air is used, e.g., when conditions permit or in an emergency (e.g., if the cooling unit  136  has failed). It would also be possible in some implementations to include a heat exchanger in the outside air module  160 . 
         [0027]    Referring to the lower center view of  FIG. 1  and  FIG. 4 , the multi-mode cooling apparatus is shown configured in an auxiliary cooling mode  108 . In the auxiliary cooling mode, the system is configured as in the closed loop operating mode described above, but additional cooling is provided by an auxiliary cooling unit  190 . In some implementations, the auxiliary cooling unit  190  has an auxiliary heat exchanger  192  with at least a cold side heat exchange portion  194  positioned outside the container  112 . A hot side heat exchange portion  196  of the heat exchanger  192  is positioned within the housing. As shown schematically in  FIGS. 1 and 4 , connections  198  link the functions of cold side heat exchange portion  194  and the hot side heat exchange portion  196  together. Air that has been cooled by the cooling unit  136  is further cooled by the heat exchanger  192  before flowing through the louver  140  under the action of the fan and exiting out into the interior  130  as cooler air. 
         [0028]    The auxiliary heat exchanger  192  may be a thermal siphon (e.g., a heat pipe), a chilled water cooler, a direct expansion cooler and/or another form of refrigerant-based heat exchanger. As is known, a direct expansion cooler/system uses a conventional refrigerant vapor expansion/compression cycle. In some implementations, the auxiliary heat exchanger  192  can be operated without operating the cooling unit  136 , such as when conditions allow for it and/or if the cooling unit  136  has failed. 
         [0029]      FIGS. 5A ,  5 B and  5 C are various views of the multi-mode cooling apparatus  102 /housing  112  and internal components and features. The housing  116  can be made of sheet metal or another suitable material. One or more internal air directing surfaces  152  as shown in the sectioned elevation view of  FIG. 5B  can be added to improve flow through the housing  112 . In  FIG. 5A , the louver  140  is shown in the closed position. In  FIGS. 5B and 5C , the louver  140  is shown in the open position. As shown, the filter  141  can be positioned approximately horizontally, and the air flow path within the housing can be configured to cause flow to travel downwardly through the filter  141  before traveling laterally to the fan  138  and the outlet opening  146 . 
         [0030]    The housing  116  can have a hinged portion covering the fan  138  that allows servicing of the fan and other components without disassembling the entire cooling apparatus  102 . By orienting the filter  141  approximately horizontally, it can be removed from the housing (such as for cleaning or replacement) by moving the hinged portion out of the way (or detaching it), as is shown in  FIG. 5C . In addition, required filtering capacity can be provided without requiring the vertical dimension of the housing  116  to be enlarged. 
         [0031]      FIGS. 6A ,  6 B and  6 C are sectioned end elevation, top plan and right side elevation views, respectively, of a multi-mode cooling apparatus  202  according to another implementation. In general, reference numerals in  FIGS. 6A-6C  have the same numeral plus  100  as corresponding elements described above. As seen in  FIG. 6A , the housing  216  can include a horizontal drip tray beneath the cooling unit  236  and aligned with the bottom surface  250 . The liquid side connections for the heat exchanger  237  can be seen in  FIG. 6A . As best seen in  FIGS. 6B and 6C , the cooling apparatus includes four fans  238 . 
         [0032]    In general, the heat exchanger  137  of the cooling unit  136  is a chilled water cooler or a direct expansion cooler, but other cooling technologies are of course possible. In general, the heat exchanger  192  is a thermal siphon, a chilled water cooler, a direct expansion cooler or another type of refrigerant-based heat exchanger. It is also possible to implement so-called conductive cooling technologies, such as the conductive cooling system marketed by Inertech that uses “standard refrigerant” instead of water and purportedly saves greatly on energy costs. 
         [0033]    Although the operations of some of the disclosed methods are described in a particular, sequential order for convenient presentation, it should be understood that this manner of description encompasses rearrangement, unless a particular ordering is required by specific language set forth below. For example, operations described sequentially may in some cases be rearranged or performed concurrently. Moreover, for the sake of simplicity, the attached figures may not show the various ways in which the disclosed methods can be used in conjunction with other methods. 
         [0034]    The disclosed methods, apparatus, and systems should not be construed as limiting in any way. Instead, the present disclosure is directed toward all novel and nonobvious features and aspects of the various disclosed embodiments, alone and in various combinations and subcombinations with one another. The disclosed methods, apparatus, and systems are not limited to any specific aspect or feature or combination thereof, nor do the disclosed embodiments require that any one or more specific advantages be present or problems be solved. 
         [0035]    In view of the many possible embodiments to which the disclosed principles may be applied, it should be recognized that the illustrated embodiments are only preferred examples and should not be taken as limiting the scope of protection. Rather, the scope of protection is defined by the following claims. We therefore claim all that comes within the scope of these claims.