JP2011220665A - Air conditioning system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air conditioning system enabling construction man-hour for the installation thereof to be reduced.SOLUTION: A plurality of blowing-out ports 3 for blowing-out conditioned air to a server room 1 are provided in the sidewall surface 2 of the server room 1. In the air conditioning system SYS, the blowing-out ports 3 are respectively on a pair of sidewall surfaces 2 opposed in the server room 1. A plurality of cooling units 10 are arranged so as to correspond to the respective blowing-out ports 3. The number of cooling units 10 to be installed is determined with sufficient margin to the heat load of the server room 1 to give redundancy. The upper part of a rack 4 is partitioned by shielding plates 5 and provided with a fan unit. The waste heat air discharged from the rack 4 is quickly transported to a return air chamber through a suction port 81 by the fan unit.

Description

  The present invention relates to an air conditioning system for managing the temperature of an air conditioning target room in which a plurality of racks that accommodate information processing devices are arranged.

  With the rapid development of information communication technology in recent years, large-scale data centers and the like are being constructed. In such a data center, a plurality of racks that accommodate information processing devices such as server devices that provide various functions and communication devices for constructing a network are arranged and arranged.

  In order to stably operate information processing devices arranged in the data center, the data center is always maintained and managed at a temperature suitable for the device operation. On the other hand, in such a data center, it is necessary to continuously operate the air conditioner for temperature maintenance, and accordingly, a relatively large amount of power is consumed.

  Therefore, a configuration has been proposed for reliably cooling the information processing device and reducing power consumption by performing cooling more efficiently.

  For example, in Japanese Patent Laid-Open No. 2002-61911 (Patent Document 1), when the cooling operation of a high-density computer room is performed by an air circulation method, the circulating air volume is reduced and the amount of refrigerant used by the refrigerator is reduced. A method for cooling a computer room is disclosed. More specifically, the computer room cooling method disclosed in Patent Document 1 discloses a configuration in which air-conditioned air from an air conditioner is blown out from under the floor at low speed through an air supply duct in the computer room. .

  Japanese Patent Laying-Open No. 2004-184070 (Patent Document 2) discloses an equipment storage rack that can sufficiently cool equipment and contribute to energy saving. More specifically, Patent Document 2 discloses a passage having an internal space under the floor, and a rack for equipment storage that is installed on both sides of the passage and supplies air from the front surface and exhausts waste heat to the upper surface or the rear surface. The structure provided with a group and an air conditioning apparatus is disclosed.

  Japanese Patent Laying-Open No. 2005-260148 (Patent Document 3) discloses an air conditioning system for a computer room that can sufficiently cool a device and contribute to energy saving. More specifically, in Patent Document 3, the equipment is contained in the rack for equipment accommodation in which the equipment is accommodated and air is supplied from the front surface and the heated air is exhausted from the upper surface or the rear surface. A configuration in which a sneak preventing device for preventing sneaking to the front side is provided is disclosed.

JP 2002-61911 A JP 2004-184070 A JP 2005-260148 A

  Each of the air conditioning systems disclosed in Patent Documents 1 to 3 described above is configured to blow out conditioned air (cool air) for cooling the air-conditioning target room from the underfloor (underfloor space) where the rack is arranged. Yes.

  However, when air-conditioned air is blown out to the air-conditioned room through the underfloor space, the pressure loss generated at the opening between the air conditioner and the underfloor space is large, and more fan power is required. In addition, the floor opening located near the opening increases the dynamic pressure (wind speed) under the floor, so that the air-conditioned air is not easily supplied to the air-conditioned room, or the air-conditioned air supplied to the air-conditioned room is not supplied. There was also a case of backflowing under the floor.

  The present invention has been made to solve such problems, and an object thereof is to provide an air conditioning system capable of reducing the power of an air conditioning mechanism necessary for supplying conditioned air to an air conditioned room. That is.

  An air-conditioning system according to the present invention is an air-conditioning system for managing the temperature of an air-conditioning target room in which a plurality of racks that accommodate information processing devices are arranged, and is in contact with the air supply surfaces of the plurality of racks. A partition for partitioning the space and a second space in contact with the exhaust surfaces of the plurality of racks, an air conditioning mechanism for supplying conditioned air to the first space, and waste heat air from the second space A return air mechanism for discharging and a blow-out port for blowing out conditioned air from the air-conditioning mechanism provided on the side wall surface in the first space of the air-conditioning target room. Are configured in units of a pair of rack groups that are arranged adjacent to each other, and the partitioning section defines a space located on the exhaust surface side of each of the pair of rack groups as another air conditioning target room. Configured to be separated from the space, the second space; The air outlet is connected to an exhaust port provided on the ceiling surface of the air conditioning target room in the space 2, and the air outlet is provided at a position where air is blown out in the direction in which the pair of rack groups extend. A total value of the occupied width is configured to be larger than a total value of the width generated by projecting the rack group onto the side wall surface, and the return air mechanism is provided at the exhaust port, and is used to promote the exhaust of the conditioned air. Part.

  Moreover, in the air conditioning system of this invention, it is preferable that a blower outlet is each provided in a pair of side wall surface which opposes.

  In the air conditioning system of the present invention, it is preferable that the air outlet is positioned so as to blow out the conditioned air with an inclination of a predetermined non-zero angle with respect to a perpendicular line from the side wall surface to the rack group.

  Further, in the air conditioning system of the present invention, the air conditioning mechanism includes a plurality of units arranged in correspondence with the plurality of outlets, and each of the plurality of units exchanges heat with the heat exchanger and the heat exchanger. It is preferable that the refrigerant supplied to the heat exchanger, including at least one fan that generates an air flow for the purpose, be maintained at a temperature higher than the dew point temperature of the air-conditioning target room.

  Further, the air conditioning system of the present invention includes a power consumption detection means for detecting power consumption in information processing devices in a plurality of racks, a temperature detection means for detecting the temperature of waste heat air discharged from the plurality of racks, Based on the power consumption detected by the power consumption detection means and the temperature detected by the temperature detection means, means for calculating the required air conditioning amount of the conditioned air supplied to the first space, and based on the calculated required air conditioning amount Preferably, the apparatus further comprises means for determining a state in which the plurality of units should operate, and control means for controlling operation / stop of the plurality of units according to the determined state to be operated.

  In the air conditioning system of the present invention, the control means operates / stops a plurality of units under the condition of the calculated number of units that need to be operated so that the cumulative operation period of each unit is leveled. Is preferably controlled.

  In the air conditioning system of the present invention, it is preferable that at least one fan is arranged so that the total fan passage area is 50% of the area of the opening of the outlet.

  Moreover, in the air conditioning system of this invention, it is preferable that a partition part contains the plate body which exists continuously from at least one part of the upper end of a rack to the ceiling surface of an air-conditioning room.

  Moreover, in the air conditioning system of this invention, it is preferable that a ventilation part is comprised by the some fan unit arrange | positioned at the air-conditioning object room in 2nd space at equal intervals.

  Further, the air conditioning system of the present invention includes a power consumption detection means for detecting power consumption in information processing devices in a plurality of racks, a temperature detection means for detecting the temperature of waste heat air discharged from the plurality of racks, Based on the power consumption detected by the power consumption detection means and the temperature detected by the temperature detection means, a means for calculating the required air volume for the exhaust from the second space, and a plurality of values based on the calculated required air volume Preferably, the apparatus further comprises means for determining a state in which the plurality of fan units should be operated, and control means for controlling operation / stop of the plurality of fan units according to the determined state to be operated.

  Further, in the air conditioning system of the present invention, the control means is configured to calculate a plurality of fan units under the condition of the calculated number of fan units that need to be operated so that the cumulative operation period of each fan unit is leveled. It is preferable to control the operation / stop.

  ADVANTAGE OF THE INVENTION According to this invention, the construction man-hour required when installing an air conditioning system can be reduced, and waste heat air can be efficiently discharged | emitted from an air-conditioning object room by a ventilation part.

1 is an overall perspective view showing an air conditioning system according to the present embodiment. It is a top view of the server room shown in FIG. It is sectional drawing seen from the III-III line arrow direction of FIG. It is sectional drawing seen from the IV-IV line arrow direction of FIG. It is a see-through | perspective perspective view of the blower outlet periphery seen from the viewpoint ViewV shown in FIG. It is sectional drawing seen from the VI-VI line arrow direction of FIG. It is a schematic diagram of the cooling unit which comprises the air conditioning system according to this Embodiment. FIG. 8 is a structural diagram of the dry coil unit shown in FIG. 7. It is a figure which shows the cross-section of the rack cooled by the air conditioning system according to this Embodiment. It is a figure which shows the structure of the front door and back plate of the rack shown in FIG. It is a figure which shows typically the state which looked up upwards from the downward direction of the shielding board of FIG. It is a figure which shows the mode in the server room seen from the viewpoint ViewXII shown in FIG. FIG. 4 is a perspective view of the fan unit of FIG. 3. It is a figure which shows the typical longitudinal cross-section of the fan unit of FIG. It is a perspective view of the return air fan mounted in the fan unit of FIG. It is a block diagram which concerns on the control structure of the air conditioning system according to embodiment of this invention. It is a figure which shows the arrangement position of the temperature sensor in the hot aisle according to this Embodiment. It is a schematic diagram which shows the data table hold | maintained at the control part shown in FIG. It is a flowchart which shows the process sequence which concerns on the operation control of the cooling unit provided with the air conditioning system according to this Embodiment. It is a flowchart which shows the process sequence which concerns on the operation control of the cooling unit provided with the air conditioning system according to this Embodiment. It is a flowchart which shows the process sequence of the return air fan selection subroutine shown to step S9 of FIG. It is a flowchart which shows the process sequence of the driving | running | working change determination subroutine shown to step S18 of FIG. It is a figure which shows typically the system configuration | structure of the comparative example with respect to the Example of this invention. It is a figure which shows typically the structure of the experimental apparatus for evaluating the air conditioning system according to embodiment of this invention. It is a figure which shows the measurement result measured using the experimental apparatus shown in FIG. It is a figure which shows the result of having calculated the temperature distribution in the experimental apparatus shown in FIG. 24 by simulation. It is a figure for demonstrating each case made into the object of simulation. It is a figure which shows the simulation result which shows the temperature distribution in a basic case. It is a figure which shows the simulation result which shows the wind speed distribution in a basic case. It is a figure which shows the wind speed distribution in each cross section shown in FIG. It is a figure which shows the simulation result which shows the temperature distribution in an upward case. It is a figure which shows the simulation result which shows the wind speed distribution in upward. It is a figure which shows the wind speed distribution in each cross section shown in FIG. It is a figure which shows the simulation result which shows the temperature distribution in a diagonally upward case. It is a figure which shows the simulation result which shows the wind speed distribution in diagonally upward. It is a figure which shows the wind speed distribution in each cross section shown in FIG. It is a top view which shows arrangement | positioning of the server room (air conditioning object room) assumed as an application destination of an air conditioning system. It is a figure which shows the simulation result of the temperature distribution in the conventional air conditioning system. It is a figure which shows the simulation result of the temperature distribution in the air conditioning system according to this Embodiment.

  Embodiments of the present invention will be described in detail with reference to the drawings. Note that the same or corresponding parts in the drawings are denoted by the same reference numerals and description thereof will not be repeated.

[A. Overview]
The air conditioning system according to the present embodiment has a configuration in which a shielding plate is provided so as to surround the outer periphery of a rack group including one or a plurality of racks arranged in the air conditioning target room. The shielding plate defines a first space in contact with the air supply side of the rack and a second space in contact with the exhaust side of the rack. As a result, it is avoided that the conditioned air supplied to the air supply side is directly exhausted without being used for cooling the rack, and the air after being used for cooling the rack is efficiently air-conditioned room Exhausted from. Hereinafter, a specific example in which the air conditioning system according to the present embodiment is applied to a server room will be described.

[B. overall structure]
FIG. 1 is an overall perspective view showing an air conditioning system SYS according to the present embodiment. FIG. 2 is a plan view of the server room shown in FIG. 3 is a cross-sectional view seen from the direction of arrows III-III in FIG. 4 is a cross-sectional view seen from the direction of arrows IV-IV in FIG.

  Referring to FIG. 1, air conditioning system SYS according to the present embodiment includes a secondary side portion 100 and a heat source portion 200. The secondary part 100 includes a mechanism for generating conditioned air, including the server room 1 that is an air-conditioning target room whose temperature is to be managed. The heat source portion 200 supplies a refrigerant that is used to generate conditioned air in the secondary side portion 100, and regenerates the refrigerant that has been used for generating conditioned air and has an increased temperature. Hereinafter, each part is explained in full detail.

(B1. Secondary part 100)
As shown in FIGS. 1 to 4, a plurality of racks 4 are arranged in an array in a server room 1 that is an air-conditioning target room whose temperature is managed by the air-conditioning system SYS according to the present embodiment. Each rack 4 accommodates various server devices (typically blade type devices) such as business servers, data servers, and Web servers, and information processing devices such as communication devices such as routers and switching hubs.

  A plurality of air outlets 3 for blowing conditioned air 18 into the server room 1 are provided on the side wall surface 2 of the server room 1. In air conditioning system SYS according to the present embodiment, air outlets 3 are provided on a pair of side wall surfaces 2 facing each other in server room 1. A plurality of cooling units 10 are arranged in association with each of the air outlets 3. The number of cooling units 10 installed is determined so as to have a sufficient margin for the heat load of the server room 1 in order to provide redundancy.

  The cooling unit 10 is a part of an air conditioning mechanism for supplying conditioned air 18 to the server room 1. More specifically, each cooling unit 10 includes a heat exchanger 13 (FIG. 3) and at least one fan 16 (FIG. 3) that generates an air flow for heat exchange with the heat exchanger 13. It consists of a dry coil unit. The conditioned air 18 generated in each of the cooling units 10 is supplied to the server room 1 from the corresponding outlet 3. The detailed structure of the cooling unit 10 will be described later.

  As shown in FIG. 2, air conditioner rooms 7 are respectively provided on the upper and lower sides of the server room 1 in the drawing. The cooling unit 10 is disposed in the air conditioning equipment room 7. The air conditioner room 7 is also a partitioned space.

  Each of the racks 4 is used to cool the information processing equipment accommodated in the rack 4 and the air supply port for sucking in the conditioned air 18 (cold air) and the information processing equipment accommodated therein. And an exhaust port for discharging waste hot air (hot air). That is, as shown in FIG. 4, the conditioned air 18 supplied by the air conditioning system SYS is inside the rack 4 from the surface (hereinafter also referred to as “air supply surface”) of the rack 4 where each air supply port is provided. And exchanges heat with the information processing device. The conditioned air 18 that has become waste heat air is discharged out of the rack 4 from a surface provided with an exhaust port (hereinafter also referred to as “exhaust surface”).

  As shown in FIGS. 1 and 2, in the server room 1, a plurality of aggregates (hereinafter also referred to as “rack groups”) including a plurality of racks 4 arranged in series adjacent to each other are arranged. The plurality of rack groups are composed of units (sets) of two (a pair) rack groups. The example shown in FIG. 1 shows an example in which four sets of rack groups are arranged on the front side and three sets of rack groups are arranged on the back side (total of seven sets of rack groups). Of course, the air conditioning system SYS according to the present embodiment can be applied to any rack arrangement. That is, the number of racks included in the rack group and the number of rack groups can be arbitrarily changed as necessary.

  Each set of rack groups is arranged adjacent to each other so that the exhaust surfaces of the racks 4 included in each rack group face each other. Therefore, in each space sandwiched by each group of racks, waste heat air from the racks 4 located on both sides is collected. Here, the blower outlet 3 is arrange | positioned in the position which blows off the conditioned air 18 which generate | occur | produced in the cooling unit 10 in the direction (longitudinal direction) where a rack group is extended.

  In the air conditioning system SYS according to the present embodiment, in each set of rack groups, a space in contact with the air supply surface of rack 4 (first space), and a space in contact with the exhaust surface of rack 4 (second space) Partition. In other words, the conditioned air 18 (cold air) supplied from the cooling unit 10 mainly exists in the space (first space) in contact with the air supply surface of the rack 4, and the space (second space) in contact with the exhaust surface of the rack 4. The space is partitioned so that waste heat air exhausted from each rack 4 mainly exists. The space where the conditioned air 18 (cold air) supplied from the former cooling unit 10 mainly exists is called “cold aisle”, and the space where the waste heat air exhausted from each rack 4 mainly exists is “hot aisle”. Called.

  Such a cold aisle and a hot aisle are partitioned using a shielding plate 5 disposed so as to surround the outer periphery of each group of racks. In other words, the shielding plate 5 that is a partition unit is configured to divide a space located on the exhaust surface side of each set of rack groups from other spaces in the server room 1 that is an air-conditioning target room.

  A part of the case of the rack 4 is used for the section between the cold aisle and the hot aisle. That is, the shielding plate 5 is provided in a space between each group of rack groups and the ceiling so as to surround the outer periphery of each group of rack groups. Further, in order to shield the space sandwiched between the opposing rack groups, shield doors are provided at both ends in the longitudinal direction of each set of rack groups as part of the shielding plate 5. In order to maintain the rack 4 from the hot aisle side, the shielding door is attached to be openable and closable so that the user can enter the hot aisle (details are not shown).

  Further, the shielding plate 5 includes a plate body that continuously exists from at least a part of the upper end of the rack 4 of the rack group to the ceiling. This is to more reliably shield the space between the rack groups.

  The hot aisle is provided with a return air mechanism for discharging waste heat air discharged from the rack 4. Specifically, a return air chamber 8 for transporting waste heat air is provided on the ceiling surface of the hot aisle, and a suction port for communicating the common return air chamber 8 with each hot aisle. 81 (see FIGS. 1, 3 and 4) is provided. The suction port 81 is provided with a fan unit 9A for forcibly exhausting waste heat air staying in the hot aisle.

  In addition, in FIG. 1, in order to understand easily, it displays with the perspective view at the time of cutting the upper part of each rack group by different height. That is, for the four sets of rack groups arranged on the front side, the structure in the vicinity of the suction port 81 provided on the uppermost part is illustrated, and for the three sets of rack groups arranged on the back side, A structure in the vicinity of the continuous shielding plate 5 is illustrated. However, the actual overall structure is substantially the same for all rack groups.

  As described above, in the air conditioning system SYS according to the present embodiment, the cold aisle is set mainly for the space of the server room 1 and the hot aisle is set locally. Thus, the air-conditioning air supply mechanism can be configured more flexibly, and waste heat air can be efficiently collected.

  As shown in FIG. 4, a plurality of temperature sensors 46 are arranged on the exhaust surface (hot aisle side) of the rack 4 in order to evaluate the heat load state in the rack 4. The temperature sensor 46 is a temperature detection unit that detects the temperature of waste heat air discharged from the rack 4. Further, as will be described later, a current sensor 47 which is a power consumption detecting means for detecting power consumption in the information processing device in the rack 4 is also arranged. In the air conditioning system SYS according to the present embodiment, the necessary air volume of the conditioned air supplied to the cold aisle is calculated based on the results detected by the plurality of temperature sensors 46 and current sensors 47. The operation of the cooling unit 10 is optimized according to the calculated required air volume. The operation logic of the cooling unit 10 will be described later.

(B2. Heat source portion 200)
The heat source portion 200 supplies a refrigerant necessary for generating conditioned air by the cooling unit 10 of the secondary side portion 100, and recools the refrigerant after the conditioned air is generated by the cooling unit 10. The cooling unit 10 of the secondary part 100 and the heat source part 200 are connected by pipes 242, 244, 218, 224.

  In the air conditioning system SYS according to the present embodiment, water is used as the refrigerant. As will be described later, the refrigerant supplied to the cooling unit 10 is maintained at a temperature higher than the dew point temperature of the server room 1 (that is, the temperature at which condensation occurs) so that condensation does not occur in the cooling unit 10. The Thus, the chiller 220 can be operated in a state where the refrigerant temperature is increased to such an extent that no condensation occurs in the cooling unit 10. Therefore, it is possible to increase the efficiency and perform the operation with less power consumption. Therefore, the chiller 220 can be continuously operated for a long period. Of course, other refrigerants, typically ammonia, hydrocarbons, carbon dioxide, chlorofluorocarbons, etc. can also be used.

  The heat source part 200 includes a return pipe 242 for transporting the refrigerant returned from the cooling unit 10 of the secondary side part 100 and a delivery pipe 244 for transporting the refrigerant supplied to the cooling unit 10 of the secondary side part 100. And is connected to the secondary side portion 100. Furthermore, the heat source portion 200 includes a radiator 210 and a chiller 220 as a mechanism for precooling the refrigerant. These refrigerant cooling mechanisms are arranged on the rear stage side of the return header 212 that integrates the return pipe 242. That is, the radiator 210 is inserted before the pipe 218 connected from the return header 212, and a bypass valve 216 for bypassing the radiator 210 is connected in parallel with the radiator 210. A plurality of chillers 220 are inserted into the piping 218 at the rear stage of the radiator 210.

  In addition, a flow meter 236 for detecting the flow rate of the refrigerant is provided in the front stage of the pipe 218.

  The radiator 210 is a device that exchanges heat by bringing the refrigerant into contact with the outside air, and dissipates the heat held by the refrigerant into the atmosphere when the outside air temperature is lower than the refrigerant temperature in winter and the like. That is, the radiator 210 performs so-called free cooling without using a refrigerator. The contact between the refrigerant and the outside air may be direct or indirect.

  Further, when the outside air temperature is higher than the refrigerant temperature in summer or the like, since the refrigerant cannot be cooled by the radiator 210, the bypass valve 216 is opened so that the refrigerant bypasses the radiator 210. .

  In particular, in the present embodiment, the waste heat air is mainly returned from the hot aisle through the suction port 81 (see FIGS. 1, 3 and 4), so that the refrigerant temperature is raised. Can effectively cool the waste heat air.

  The chiller 220 cools the returned refrigerant. It is preferable to connect a plurality of chillers 220 in parallel so that the capacity can be changed according to the amount of heat held by the refrigerant (the amount of heat recovered from the server room 1). Moreover, it is preferable to prepare at least one spare machine in case of a failure, and therefore it is common to arrange a plurality of chillers 220 in the air conditioning system SYS. The chiller 220 may be of any type as long as it has an ability corresponding to the amount of heat generated in the server room 1. For example, as the cooling method, either an air cooling type or a water cooling type may be adopted.

  The refrigerant cooled by each chiller 220 is output to the supply header 214 through the outlet side pipe 224. The refrigerant is transported from the supply header 214 to the cooling unit 10 disposed along one side wall surface of the server room 1 and the cooling unit 10 disposed on the other side wall surface.

  The return header 212 and the supply header 214 are provided with temperature sensors 232 and 234 for detecting the refrigerant temperature, respectively. Based on the respective refrigerant temperatures detected by these temperature sensors 232 and 234 and the refrigerant flow rate detected by the flow meter 236, the number of operating chillers 220 is controlled. That is, in the heat source portion 200, the chiller 220 and / or the radiator 210 are maintained so that the refrigerant temperature (the temperature of the refrigerant supplied to the cooling unit 10) in the supply header 214 detected by the temperature sensor 234 is maintained at the target value. The number of operating units / capacity is controlled. The refrigerant supplied to the cooling unit 10 is set to a temperature higher than the dew point temperature of the server room 1 that is the air conditioning target room. As an example, the target value of the refrigerant temperature supplied to the cooling unit 10 is set to 13 to 15 ° C. Further, based on the difference between the refrigerant temperature in the return header 212 detected by the temperature sensor 232 and the refrigerant temperature in the supply header 214 detected by the temperature sensor 234, and the refrigerant flow rate detected by the flow meter 236, the server The heat load amount in the room 1 is calculated, and the number / capacity of the chillers 220 operated is controlled.

[C. Side wall outlet]
Next, the air outlet 3 provided in the side wall surface 2 of the server room 1 will be described.

  FIG. 5 is a perspective view of the periphery of the air outlet 3 viewed from the viewpoint ViewV shown in FIG. FIG. 6 is a cross-sectional view seen from the direction of arrows VI-VI in FIG.

  With reference to FIG. 5, the blower outlet 3 provided in the side wall surface 2 is comprised so that the blown-out conditioned air may face the direction (longitudinal direction) where the rack group extends, and the front surface thereof has a lattice-like shape. A blowing frame is provided. Thereby, from the blower outlet 3, conditioned air is discharged from the near side (left side of the sheet) to the back side (right side of the sheet) of the rack group.

  In particular, in the air conditioning system SYS according to the present embodiment, the area occupied by the air outlet 3 in the side wall surface 2 is designed to be as large as possible. This is because by ensuring a wider blowing area, it is possible to reduce the blowing speed for realizing the necessary supply amount of the conditioned air amount. That is, since it is sufficient to supply the conditioned air at a lower blowing speed, it is possible to employ a fan having a high blowing efficiency and to reduce the power required for blowing the conditioned air. Furthermore, the influence of the dynamic pressure in the vicinity of the blower outlet 3 can be reduced by adopting a lower blowout speed. As a result, it is not necessary to provide a diffusion plate (so-called baffle plate) for dynamic pressure and static pressure conversion, which is provided to suppress the influence of dynamic pressure. Therefore, the structure is simplified and space saving is realized, and the pressure loss related to the blowing is reduced, and the power required for blowing the conditioned air can be reduced.

  More specifically, in the air conditioning system SYS according to the present embodiment, the total value of the width occupied by the air outlet 3 on the side wall surface 2 is larger than the total value of the width generated by projecting the rack group onto the side wall surface 2. Configured. As an example, consider a case where one outlet 3 is provided on the side wall surface 2 for each pair of rack groups (two rows of rack groups) (the rack arrangement shown in FIG. 2). . At this time, the width indicated by each outlet 3 in the side wall surface 2 is A, and the total value of the width generated by projecting the pair of rack groups onto the side wall surface 2 is 2B (B + B). At this time, the air outlet 3 is provided so that the width A of the air outlet 3> the total width 2B of the projection image 400.

  Moreover, when it sees about the height of the blower outlet 3, the length which covers the substantially whole rack 4 is preferable. It is preferable to blow out the conditioned air from a range of at least 60% of the height of the rack 4.

  As shown in FIG. 2, in the air conditioning system SYS according to the present embodiment, the cold aisle occupies more space in the server room 1. The cold aisle is supplied with conditioned air from the outlet 3. Therefore, when it sees about the area of the blower outlet 3, it is preferable that the blower outlet 3 occupies 50% or more of the whole area of the side wall surface 2 in which the blower outlet 3 is formed. From another viewpoint, it is preferable that the area of the air outlet 3 has an area substantially similar to the area (projected image 400) generated by projecting the rack group onto the side wall surface 2.

  Moreover, it is preferable that the blowing speed from the blower outlet 3 of conditioned air shall be 1.0-2.0 m / sec.

[D. Cooling unit]
Next, the cooling unit 10 will be described.

  FIG. 7 is a schematic diagram of cooling unit 10 constituting air conditioning system SYS according to the present embodiment. FIG. 8 is a structural diagram of the dry coil unit 12 shown in FIG.

  Referring to FIG. 7, the cooling unit 10 disposed in association with each air outlet 3 includes a plurality of dry coil units 12. FIG. 7 shows a configuration in which four dry coil units 12 are arranged in a grid of 2 × 2 as an example.

  As shown in FIG. 8, each dry coil unit 12 includes a heat exchanger 13 and at least one fan 16 (two in the example shown in FIG. 8) that generates an air flow for heat exchange with the heat exchanger 13. X 4 columns in total). The heat exchanger 13 that generates heat transfer with the air flow generated by the rotation of the fan 16 includes a refrigerant supply port 14 and a refrigerant discharge port 15. The refrigerant supplied from the heat source portion 200 is injected from the refrigerant supply port 14, passes through the radiator portion of the heat exchanger 13, and is then discharged from the refrigerant discharge port 15. The fan 16 is an axial fan that rotates blades having blades having a predetermined angle with respect to a rotation plane. A plug fan may be employed as the fan 16.

  Note that a filter for capturing dust or the like may be provided in the front stage of the heat exchanger 13 or the rear stage of the fan 16.

  In particular, in the air conditioning system SYS according to the present embodiment, it is preferable that the blower outlet 3 having as large an area as possible is provided on the side wall surface 2 and the blowout speed of the conditioned air from the blower outlet 3 is as low as possible. Therefore, as shown in FIG. 7, the total passage area 19 of the fan 16 included in the cooling unit 10 (a cross-sectional area that generates an air flow when the fan 16 rotates) 19 is 50% or more of the opening area of the outlet 3. It is preferable to do so. Thus, by arranging the plurality of fans 16 so that the passage area has a relatively large ratio with respect to the opening area of the air outlet 3, conditioned air can be discharged from the entire air outlet 3. At the same time, it is possible to reduce the deviation in the outlet cross section of the outlet 3.

  As described above, the heat source portion 200 is controlled so as to supply the cooling unit with a constant temperature refrigerant that does not cause condensation in the cooling unit 10. Therefore, the generation capacity (cooling capacity) of the conditioned air by each cooling unit 10 is adjusted by changing the rotation speed of the fan 16. Therefore, in air conditioning system SYS according to the present embodiment, a configuration is employed in which fan 16 can be speed-controlled. Typically, the speed of the motor connected to the fan 16 is controlled. Note that a VVVF (Variable Voltage Variable Frequency) device such as an inverter is employed for the shift control.

[E. Rack structure]
Next, the flow of conditioned air in the rack 4 will be described.

  FIG. 9 is a diagram showing a cross-sectional structure of rack 4 that is cooled by air conditioning system SYS according to the present embodiment. FIG. 10 is a diagram showing the structure of the front door 41 and the back plate 42 of the rack 4 shown in FIG.

  Referring to FIG. 9, a plurality of shelves 48 for accommodating information processing equipment DEV are provided inside rack 4. In addition, a cable take-in opening 44 for guiding a communication cable connected to the information processing device DEV to the wiring pit is formed at the bottom of the rack 4. Further, the cable taking-in opening 44 may be used for guiding a sensor cable such as a temperature sensor 46 (see FIG. 2) attached to the rack 4.

  A top plate outlet 43 for discharging waste hot air (hot air) from inside the rack 4 is formed on the top surface of the rack 4. The top plate outlet 43 is provided with a metal mesh or louver so that foreign matter does not fall into the rack 4.

  As shown in FIG. 10, narrow louver blades (blade-like plates) 45 are laterally arranged on the front door 41 of the rack 4 corresponding to the air supply surface and the rear plate 42 of the rack 4 corresponding to the exhaust surface. A louver-like structure in which a plurality of pieces are attached at regular intervals and at regular angles is employed. 9 and 10, the attachment angle of the louver blade 45 is indicated by a broken line.

  The louver blade 45 on the front door 41 side is inclined upward from the outside to the inside of the rack 4 in order to efficiently take in the conditioned air (cold air) existing in the cold aisle. When taking in, the air-conditioned air blows up from the lower side to the upper side. On the other hand, the louver blade 45 on the back plate 42 side is inclined upward from the inside to the outside of the rack 4 in order to efficiently discharge waste heat air (hot air) generated inside the rack 4. When the waste heat air is released, the waste heat air rises from the lower side to the upper side.

  The louver blade 45 is formed with a number of punching openings in a lattice shape so that the inside of the rack 4 can be visually recognized through the punching openings. For this reason, the indicator lamp of the information processing device DEV accommodated in the rack 4 can be easily confirmed from the outside of the rack. The size of the punching opening is a small size that does not allow a rod-shaped foreign object such as a ballpoint pen to enter from the outside of the rack. Note that the louver blade 45 may have a curved surface.

  Thus, the conditioned air guided to the front door 41 is rectified by the louver blade 45 and smoothly attracted to the information processing device DEV mounted on the shelf 48 inside the rack 4. The waste heat air after cooling the information processing device DEV inside the rack 4 is rectified by the louver blade 45 provided on the back plate 42 and exhausted from the back of the rack 4. Alternatively, it is discharged from a top plate outlet 43 formed at the top of the rack 4.

  The upper part of the rack 4 is partitioned from the cold aisle by a shielding plate 5, and a suction port 81 is provided in a hot aisle that is a space surrounded by the shielding plate 5, and a fan unit is provided in the suction port 81. Since 9A is provided, the waste heat air discharged from the rack 4 is quickly transferred to the return air chamber 8 through the suction port 81 by the fan unit 9A.

  Further, the hot aisle air is forcibly exhausted to the return air chamber 8 by the fan unit 9A, so that the hot aisle can be kept at a negative pressure as compared with the cold aisle. Thereby, the flow of the air sent to the hot aisle through the inside of the rack 4 by the conditioned air supplied to the cold aisle can be promoted, and thereby the rack 4 can be reliably cooled.

  Thus, the conditioned air is easily attracted into the rack 4 and the waste heat air is easily discharged from the rack 4, so that the information processing device DEV in the rack 4 can be efficiently cooled. .

[F. Return Air Fan]
As described above, in the present embodiment, the fan unit 9 </ b> A is provided in the suction port 81 on the ceiling of the server room 1.

  FIG. 11 schematically shows a state where the upper side is looked up from below the shielding plate 5. FIG. 12 is a diagram showing a state in the server room viewed from the viewpoint ViewXII shown in FIG. FIG. 13 is a perspective view of the fan unit 9A, and FIG. 14 is a schematic longitudinal section of the fan unit 9A.

  Referring to FIGS. 11 to 14, in server room 1, a plurality of fan units 9 </ b> A are installed in a ceiling surface 8 </ b> A above the hot aisle. In FIG. 11, the rack 4 positioned below the shielding plate 5 is indicated by a broken line. The fan units 9A are arranged in a row on the ceiling surface located above the space (hot aisle) between the plurality of racks 4 facing each other.

  The fan units 9A are preferably provided at equal intervals in order to convey the air in the hot aisle to the return air chamber 8 evenly as a whole. However, it is considered that the arrangement of the fan unit 9A often follows the arrangement of the suction ports 81 on the ceiling surface.

  Each fan unit 9A includes a return air fan 9B. The return air fan 9B has a plurality of wings as shown in FIG. When the fan motor (fan motor 9C described later) is driven, the blades of the return air fan 9B are rotated, and the exhaust air in the hot aisle is conveyed to the return air chamber 8 through the suction port 81.

[G. Control logic]
Next, control logic for performing operation control of the cooling unit 10 and the fan unit 9A will be described. Operation control of the cooling unit 10 and the fan unit 9A is mainly executed by the controller 9 shown in FIG.

  The controller 9 receives field information from the temperature sensor 46 and the current sensor 47 and gives a control command to the cooling unit 10 and the fan unit 9A. That is, the controller 9 is connected to the cooling unit 10 and the like provided in the server room 1 by wiring. The controller 9 is wired to each temperature sensor 46 and each current sensor 47 attached to each rack group.

  The controller 9 is typically housed in a control panel provided separately in the nearby machine room. Instead of this, the controller 9 may be configured by a monitoring device installed on another floor in the building. Alternatively, the controller 9 may be accommodated in any rack 4. Further alternatively, the controller 9 may be configured by a control device mounted in association with any of the plurality of cooling units 10 and the fan unit 9A. Typically, the controller 9 includes a microcomputer that executes processing according to a stored program.

  The controller 9 included in the air conditioning system SYS according to the present embodiment mainly has the following four functions.

(1) Calculation of necessary air volume for exhausting room air from hot aisle to return air chamber 8 and determination of state in which fan unit 9A should be operated based on it (2) Fan unit according to the determined state to be operated 9A (return air fan 9B) air flow (rotation speed) and operation / stop control (3) Calculation of required air volume of conditioned air supplied to cold aisle and determination of the state in which the cooling unit should operate (4) According to the determined state to be operated, the amount of air blown (number of rotations) and control of operation / stop of the cooling unit 10, that is, in the air conditioning system SYS according to the present embodiment, according to the heat load amount in the rack 4, etc. The supply amount (air volume) of the conditioned air is varied. As a result, it is possible to avoid a situation in which the conditioned air supplied in comparison with the amount of heat generated in the rack 4 is insufficient to cause a temperature rise, and the amount of heat generated in the rack 4 is excessive. It is possible to avoid a situation in which power consumption is excessive due to supply of conditioned air.

  Further, in the air conditioning system SYS, the hot standby mode and the cold standby mode can be switched as a configuration in which the supply amount (air volume) of the conditioned air is variable. Here, the hot standby mode means that all of the installed cooling units 10 are operated with a supply amount smaller than the maximum supply capacity, and even if a certain cooling unit 10 fails, the remaining cooling units 10 In this mode, the temperature management of the server room 1 can be continued by increasing the supply amount of the conditioned air from 10. On the other hand, the cold standby mode is a state in which only some of the installed cooling units 10 are operated and the remaining cooling units 10 are stopped. If a certain cooling unit 10 fails, the operation of the stopped cooling unit 10 is resumed, and the temperature management of the server room 1 is continued.

  In particular, in the air conditioning system SYS according to the present embodiment, when the cold standby mode is selected, the cooling unit 10 necessary for supplying the conditioned air so that the cumulative operation period of the cooling unit 10 is leveled. The operation / stop of the cooling unit 10 is controlled according to the number of.

In addition, the ventilation temperature of conditioned air can also be controlled.
Details of these functions will be described below.

(G1. Control structure)
FIG. 16 is a block diagram relating to a control structure of air conditioning system SYS according to the embodiment of the present invention.

  Referring to FIG. 16, controller 9 includes a data output unit 93 and a data input unit 94. The data output unit 93 includes a DCU control unit 92 and a return air fan control unit 91. The DCU control unit 92 controls the fan rotation speed and operation / stop of each cooling unit 10. The fan rotation speed and operation / stop of the return air fan 9B of each fan unit 9A are controlled. The data input unit 94 includes a current data input unit 96 to which the detection value of the current sensor 47 is input, and a temperature data input unit 98 to which the detection value of the temperature sensor 46 is input.

  The temperature data input unit 98 receives the detected values of the supply air temperature and the return air temperature detected by a temperature sensor (not shown).

  The DCU control unit 92 calculates the required air conditioning amount of the entire server room 1 and controls the supply amount of conditioned air from the plurality of cooling units 10 based on the calculation result. More specifically, the DCU control unit 92 detects the power consumption in the information processing device DEV accommodated in the rack 4 and the temperature of the waste heat air discharged from the rack 4, and uses these detection results as the detection results. Based on this, the required air conditioning amount of the entire server room 1 is calculated. More specifically, each rack group has a temperature sensor 46 for detecting the temperature of waste heat air discharged from the rack group, and a current sensor 47 for calculating power consumption of the stored information processing equipment. The required air conditioning amount is calculated for each hot aisle surrounded by a pair of rack groups from the detection values of these sensors. Then, the total required air conditioning amount calculated for each hot aisle corresponding to each group of racks is obtained, and a value obtained by adding a predetermined compensation value is set as the required air conditioning amount for the entire server room 1. This compensation value is a component including a margin in which the conditioned air supplied from the blowout port 3 takes into account the waste heat imbalance of the racks 4 constituting each hot aisle.

  The return air fan control unit 91 calculates a necessary air volume for each of the two (a pair) rack groups, and controls an air flow for exhaust from the plurality of fan units 9A based on the calculation result. More specifically, the return air fan control unit 91 detects the power consumption in the information processing device DEV accommodated in the rack 4 and the temperature of the waste heat air discharged from the rack 4, and detects these. Based on the result, the required air volume for each pair of rack groups is calculated. More specifically, each rack group has a temperature sensor 46 for detecting the temperature of waste heat air discharged from the rack group, and a current sensor 47 for calculating power consumption of the stored information processing equipment. The necessary air volume for each hot aisle surrounded by a pair of rack groups is calculated from the detection values of these sensors. And the sum total of the required air volume calculated for every hot aisle corresponding to each group of racks is obtained.

  1, the refrigerant temperature in the supply header 214 detected by the temperature sensor 234 (the temperature of the refrigerant supplied to the cooling unit 10) and the refrigerant temperature in the return header 212 detected by the temperature sensor 232 (the cooling unit). The amount of heat load in the server room 1 may be calculated on the basis of the difference between the refrigerant temperature and the refrigerant flow rate returned from 10, and the required air conditioning amount may be calculated from the calculated heat load.

  Further, a return air temperature sensor (return air temperature sensor 23 in FIG. 16) for detecting the return air temperature is provided at the suction port 81, and a supply air temperature sensor (for detecting the supply air temperature at the outlet 3 ( The air supply temperature sensor 24) of FIG. 16 is provided, and the amount of heat load in the server room 1 is calculated based on the difference between the detected temperatures, and the required air conditioning amount and required air amount are calculated from the calculated heat load amount. May be.

  As described above, the DCU control unit 92 can switch between the hot standby mode and the cold standby mode. The DCU control unit 92 executes the following processes depending on which standby mode is selected.

  In the hot standby mode, the DCU control unit 92 calculates the required air conditioning amount for the entire server room 1 and then determines the supply air conditioning amount to be shared by each cooling unit 10 according to the calculated required air conditioning amount. And the control part 92 controls the inverter (not shown) which drives a fan with respect to each cooling unit 10 so that it may become the determined blowing speed.

  In the cold standby mode, the DCU control unit 92 calculates the required air conditioning amount for the entire server room 1 and then calculates the calculated required air conditioning amount and the maximum supply air conditioning amount that can be supplied by the currently operated cooling unit 10. Compare Then, when the maximum supplied air conditioning amount is less than the required air conditioning amount, a number of cooling units 10 that can satisfy the required air conditioning amount are newly operated. Conversely, when an excessive amount of air conditioning exceeding a predetermined threshold is supplied with respect to the required amount of air conditioning, the number of cooling units 10 operated so that the difference between the supplied air conditioning amount and the required air conditioning amount is equal to or less than the threshold value. To stop.

  When starting the operation of the cooling unit 10 or stopping the cooling unit 10, the DCU control unit 92 causes the cooling unit 10 to be operated or stopped so that the accumulated operation time of each cooling unit 10 is leveled. Select. By adopting such a logic, the air conditioning load by each cooling unit 10 can be distributed.

  As described above, in any standby mode, the DCU control unit 92 determines the state in which the cooling unit 10 should operate based on the calculated required air conditioning amount, and performs cooling according to the determined state to operate. The operation / stop of the unit 10 is controlled.

  When the return air fan control unit 91 starts the operation of the fan unit 9A or stops the fan unit 9A, the cumulative operation time of each fan unit 9A (the return air fan 9B) is leveled. The fan unit 9A to be operated or stopped is selected. By adopting such a logic, it is possible to distribute the load by each fan unit 9A.

  The controller 9 holds the accumulated operation time of each cooling unit 10 and each fan unit 9A in the built-in memory.

(G2. Temperature sensor and current sensor)
Next, the temperature sensor 46 and the current sensor 47 will be described.

  FIG. 17 is a diagram showing an arrangement position of the temperature sensor in the hot aisle according to the present embodiment. 17A shows the mounting position of the temperature sensor 46 in the longitudinal direction of the rack group, and FIG. 17B shows the mounting position of the temperature sensor 46 in the short direction of the rack group. FIG. 18 is a schematic diagram showing a data table held in the data output unit 93 shown in FIG.

  As shown in FIGS. 17 (a) and 17 (b), in each rack group in which a plurality of racks 4 are arranged adjacent to each other, a temperature sensor is provided at predetermined intervals (for example, 3 meters). 46 are arranged in the upper space of the rack 4 (the height position of the shielding plate 5), the upper stage of the rack 4, and the lower stage of the rack 4, respectively. In FIG. 17, the temperature sensor 46. H, temperature sensor 46. M, temperature sensor 46. Each is denoted as L. These temperature sensors are preferably attached to the hot aisle side.

  FIG. 17A shows an example in which one set of temperature sensors 46 is attached to each of the three racks 4, but the attachment interval of the temperature sensors 46 can be arbitrarily changed. For example, the temperature sensors 46 may be attached to all the racks 4. Further, the mounting position of the temperature sensor 46 in the vertical direction can be arbitrarily changed. For example, the temperature sensor 46 may be attached only to the middle position of the rack 4. Conversely, the temperature sensor 46 may be attached to more detection points. Further, the temperature sensor 46 may be attached inside the rack 4.

  For example, the controller 9 identifies each temperature sensor 46 as [TH1, TM1, TL1], [TH2, TM2, TL2],..., [THn, TMn, TLn] and identifies the detected value for each rack group. A pair of rack groups forming the hot aisle are collectively identified as [1L, 1R], [2L, 2R],... [3L, 3R].

  The controller 9 holds the detection values from the temperature sensor 46 and the current sensor 47 attached to each rack group in a data table as shown in FIG. A data table as shown in FIG. 18 is configured in a memory included in the controller 9. Furthermore, the controller 9 updates the detection values from the temperature sensor 46 and the current sensor 47 each time a predetermined update condition is satisfied. Based on the data held in this manner, the state in which each cooling unit 10 should be operated is determined, and the rotation speed and operation / stop of the cooling unit 10 are controlled according to the determined state to be operated.

  The current sensor 47 is attached at an appropriate position according to the power supply form to each rack 4. For example, when wiring is independently made from the common power supply panel in the server room 1 to each rack 4, the current sensor 47 is attached on each wiring. In this case, the power consumption in the information processing device DEV can be detected for each rack. Or when providing a power supply part separately in a rack group, the current sensor 47 is attached to the output side of each power supply part. In this case, the power consumption in the information processing device DEV can be detected for each rack group.

(G3. Processing procedure)
(G3-1. Operation control)
FIGS. 19 and 20 are flowcharts showing a processing procedure related to operation control of cooling unit 10 and fan unit 9A provided in air conditioning system SYS according to the present embodiment. FIG. 21 is a flowchart showing the processing procedure of the return air fan selection subroutine shown in step S9 of FIG. FIG. 22 is a flowchart showing the procedure of the operation change determination subroutine shown in step S18 of FIG. Each step shown in FIGS. 19 to 22 is typically provided by the controller 9 executing a program.

  Referring to FIG. 19, the controller 9 acquires a temperature detection value from each temperature sensor 46 (step S1). Subsequently, the controller 9 acquires a current detection value from each current sensor 47 (step S2). The controller 9 stores the acquired temperature detection value and current detection value in a data table as shown in FIG. 18 for each rack group.

  Subsequently, the controller 9 determines whether any of the detected values acquired from the temperature sensor 46 and the current sensor 47 exceeds a predetermined abnormality determination value (step S3). When it is determined that there is a detected value exceeding the abnormality determination value (YES in step S3), the controller 9 specifies a sensor corresponding to the detected value exceeding the abnormality determination value and outputs an alarm signal. (Step S4). In response to the alarm signal, an alarm lamp provided in the controller 9 or the like is turned on or an alarm sound is generated. Alternatively, the alarm signal from the controller 9 is output to another monitoring device or the like connected to the controller 9 by wire or wirelessly.

  Subsequently, the controller 9 calculates a representative temperature for each of the pair of rack groups constituting the hot aisle based on the acquired temperature detection value from the temperature sensor 46 (step S5). The representative temperature indicates the heat load state of each hot aisle. As an example, the controller 9 multiplies the temperature detection values from the temperature sensors 46 belonging to the same hot aisle by corresponding weighting factors, and calculates the sum of the respective values obtained by multiplying the weighting factors. Calculated. Note that the weighting coefficient associated with each temperature sensor 46 is determined by the administrator of the server room 1 in advance in consideration of the power consumption of the information processing device DEV accommodated in each rack 4. Can be set to

  Next, on the basis of the input current data, the necessary heat amount for processing is calculated for each of the two rows of rack groups constituting the hot aisle (step S6).

  Next, based on the calculated representative temperature, the amount of heat required for processing, and the space size (air volume) of the hot aisle, the required air volume is calculated for each of the two rows of rack groups constituting the hot aisle (step S7).

  Next, the number of fan units (return air fans) that need to be operated is calculated for each hot aisle based on the blowing capacity per fan unit 9A and the required air volume calculated in step S7. (Step S8). The controller 9 stores in advance the air blowing capacity of each fan unit 9 </ b> A in a memory included in the controller 9.

(G3-2. Return air fan selection control)
Next, a return air fan selection process is performed (step S9). The return air fan selection process will be described in detail with reference to FIG.

  First, it is determined whether or not the detected value of the temperature sensor 46 exceeds a predetermined standard temperature for the two rows of racks forming the hot aisle (step S90).

  If it is determined that the temperature exceeds the fan, the temperature sensor 46 determined to exceed the standard temperature among the plurality of temperature sensors 46 cools the corresponding rack with priority. Control is performed so that the unit 9A is preferentially operated (step S98), and the process is returned to FIG.

  On the other hand, if it is determined that the number does not exceed, it is determined whether or not the current number of operating fan units 9A (return air fans 9B) is less than the required number of return air fans calculated in step S8 (step S8). S91). If the number of return air fans 9B that are in operation is less than the number calculated in step S8, the return air fans 9B that are stopped are prioritized from those with the shortest cumulative operation time. Then, it is selected as an activation target (step S92). For example, when it is necessary to start two return air fans 9B newly, the shortest cumulative operation time among the return air fans 9B currently stopped and the next short operation time Are selected as activation targets.

  The accumulated operation time of the return air fan 9B is stored in the memory of the controller 9 for each return air fan 9B. The controller 9 updates the corresponding accumulated operation time as needed for the return air fan 9B in operation. When the operation of the return air fan 9B is stopped, the counting of the accumulated operation time of the corresponding return air fan 9B is stopped. The accumulated operation time stored by the controller 9 is, for example, an accumulated time based on when the return air fan 9B is newly installed in the server room 1.

  However, for the cumulative operating time of the return air fan 9B that has undergone maintenance or the like, the controller 9 may be configured so that the data of the cumulative operating time can be reset at that stage. Alternatively, by performing a predetermined reset operation on the controller 9, the accumulated operating time data may be reset for the return air fan 9B desired by the operator. Alternatively, the controller 9 may autonomously reset the accumulated operating time data of all the return air fans 9B every time a predetermined period elapses. The predetermined period may be arbitrarily set such as one day, one month, or one year. That is, the cumulative operation time in the present embodiment is not limited to the time measured with reference to the time when the return air fan 9B is newly installed in the server room 1.

  If NO is determined in step S91, it is determined whether or not the current number of operating return air fans 9B exceeds the required number of return air fans calculated in step S8 (step S93). If the current number of operating return air fans 9B exceeds the required number of return air fans calculated in step S8, the highest number of operating return air fans 9B having the longest accumulated operation time is prioritized. Then, it is selected as a stop target (step S94). For example, when it is necessary to stop two return air fans 9B newly, the longest cumulative operation time among the return air fans 9B that are currently operating and the one that has the next long operation time Are selected as stop targets.

  If it is determined NO in step S93, that is, if the current number of operating return air fans 9B matches the number of required return air fans calculated in step S8, the number of operating return air fans 9B is determined. It is determined whether or not there is a return air fan 9B that has been operating beyond a predetermined continuous operation time. For example, when the required air volume for the server room 1 does not change over a long period of time, the return air fan 9B to be operated / stopped is not replaced only by the processing in steps S91 to S94. In such a case, there is a possibility that the accumulated operating time of each return air fan 9B is biased. Therefore, in step S95, even in such a case, the return air fan 9B continuously operating for a predetermined time is detected in order to prevent the accumulated operation time of each return air fan 9B from being biased.

  If YES is determined in step S95, the corresponding return air fan 9B is selected as a stop target (step S96). In place of this, priority is selected from the ones of the return air fans 9B that are stopped that have the shortest accumulated operation time as the activation target (step S97).

  After step S92, S94, or S97, the return air fan selection process ends. If it is clear that the required number of return air fans frequently changes, the processing of steps S95 to S97 may be omitted.

  Returning to FIG. 19, after the return air fan 9B to be started or stopped is selected in step S9, the fan unit 9A is controlled for each hot aisle based on the required number of fan units calculated in step S8 (step S10). ). For example, when the number of necessary fan units (return air fans) for a hot aisle is 6 and the number of current fan units (return air fans) is 5, the number of fan units 9A being stopped is one. An activation signal is output for each. Further, when the required number of fan units for a certain hot aisle is three and the current number of operating fan units is five, stop signals are output to two of the operating fan units 9A.

  The selection of the fan unit to be stopped or started may be performed by the same control procedure as the return air fan selection process shown in FIG. 21 so that the cumulative operation time of the fan units in the hot aisle is leveled. . Alternatively, the number of fan units to be operated and the fan units to be operated correspondingly may be determined in advance. For example, a fan unit that is driven preferentially from a fan unit provided on the side closer to one end of the first passage portion constituting the hot aisle and goes toward the other end of the first passage portion as the required number of drives increases. It is conceivable to drive sequentially.

  Next, based on the acquired current detection value, the controller 9 calculates the power consumption in the information processing device separately from the pair of rack groups constituting the hot aisle (step S11).

  Further, the controller 9 determines the necessary air conditioning amount separately for the pair of racks constituting the hot aisle based on the representative temperature calculated in step S5, the power consumption calculated in step S11, and the cold aisle space size (volume). Is calculated (step S12). And the controller 9 calculates the sum total about the required air-conditioning quantity for every pair of rack group calculated in step S12, and calculates the total request | required air volume QDCU of the blowing air volume from the cooling unit 10 (step S13).

  Subsequently, the controller 9 determines the currently selected standby mode (step S14).

  When the hot standby mode is selected (“hot standby” in step S14), the controller 9 divides the total required air volume QPCU calculated in step S13 by the number of operating cooling units 10 to obtain each cooling unit. The air-conditioning air volume qDCU to be shared by 10 is calculated (step S15). Then, the controller 9 gives a speed control command to the inverter that drives the fan 16 so that the fan 16 rotates at a speed corresponding to the air-conditioning air volume qDCU calculated in step S15 (step S16).

  On the other hand, when the cold standby mode is selected (“cold standby” in step S14), the controller 9 uses the total required air volume QDCU calculated in step S13 as the maximum air conditioning air volume qDCU_max for the cooling unit 10 alone. The required number of cooling units 10 to be operated in order to provide the conditioned air of the total required air volume QDCU is calculated (step S17). Subsequently, the controller 9 determines whether or not the cooling unit 10 to be operated needs to be changed by executing an operation change determination subroutine (step S18). As will be described later, the cooling unit 10 to be operated is determined by executing the operation change determination subroutine shown in step S18. Subsequently, the controller 9 divides the total required air volume QDCU calculated in step S13 by the number of cooling units 10 determined as the operation target, so that the air conditioning air volume qDCU to be shared by each cooling unit 10 to be operated. Is calculated (step S19). Then, the controller 9 gives an operation start command to the inverter corresponding to the cooling unit 10 determined as the start target in step S18, and also instructs the inverter corresponding to the cooling unit 10 determined as the stop target in step S18 to stop the operation. (Step S20). Furthermore, the controller 9 gives a speed control command to the inverter that drives the fan 16 so that the fan 16 rotates at a speed corresponding to the air-conditioning air volume qDCU calculated in step S19 (step S21).

  For example, in order to provide conditioned air with the total required air volume QDCU, if the required number of operating cooling units 10 is six and the current operating number of cooling units 10 is five, An operation start command is given to one of them. In addition, in order to provide the conditioned air of the total required air volume QDCU, when the required number of operating cooling units 10 is 5 and the current operating number of cooling units 10 is 6, An operation stop command is given to one of them.

(G3-3. Operation change judgment)
Next, processing contents in the operation change determination subroutine executed in step S18 will be described.

  Referring to FIG. 22, controller 9 determines whether or not the current operating number of cooling units 10 is less than the required operating number of cooling units 10 calculated in step S17 (S181).

  When the current operating number of cooling units 10 is less than the required operating number of cooling units 10 calculated in step S17 (in the case of YES in step S181), the controller 9 stores each of the built-in memories. With reference to the accumulated operating time of the cooling unit 10, the cooling unit 10 that is stopped is preferentially selected from the ones with the shortest accumulated operating time as the activation target (step S182). For example, when two cooling units 10 need to be newly activated, the cooling unit 10 having the shortest cumulative operating time and the next shortest operating time among the currently stopped cooling units 10 are started. Selected as a target. Then, the process returns to step S19 in FIG.

  On the other hand, when the current operation number of the cooling units 10 satisfies the required operation number of the cooling units 10 calculated in step S17 (NO in step S181), the current operation of the cooling unit 10 is performed. It is determined whether or not the number exceeds the required number of cooling units 10 calculated in step S17 (step S183).

  When the current number of operating cooling units 10 exceeds the required number of operating cooling units 10 calculated in step S17 (in the case of YES in step S183), the controller 9 includes the cooling units 10 in operation. In this case, the object to be stopped is preferentially selected from those having the longest accumulated operation time (S184). For example, when it is necessary to stop two cooling units 10 newly, the cooling unit 10 with the longest accumulated operating time and the next one with the longest operating time are stopped among the currently operating cooling units 10. Selected as a target. Then, the process returns to step S19 in FIG.

  If NO is determined in step S183, that is, if the current number of operating cooling units 10 matches the required number of operating cooling units 10 calculated in step S17, the currently operating cooling unit 10 Then, it is determined whether or not there is a cooling unit 10 that has been operating beyond a predetermined maximum continuous operation time (step S185). For example, when the required air conditioning amount of the entire server room 1 does not change over a long period of time, the cooling unit 10 to be operated / stopped is not replaced only by the determination processing in steps S181 and S183. Therefore, there is a possibility that the accumulated operation time between the cooling units 10 may be biased. Therefore, in step S25, even in such a case, the cooling unit 10 that has been continuously operated over a predetermined time is stopped so that the accumulated operation time between the cooling units 10 is not biased. .

  When there is a cooling unit 10 that has been operating beyond a predetermined maximum continuous operation time among the currently operating cooling units 10 (YES in step S185), the controller 9 determines that the corresponding cooling unit 10 Is selected as a stop target (step S186). Subsequently, instead of the cooling unit 10 selected as the stop target, the cooling unit 10 that is stopped is selected as the start target preferentially from the one having the shortest accumulated operation time (step S187). Then, the process returns to step S19 in FIG.

  If there is no cooling unit 10 that has been operating beyond the predetermined maximum continuous operation time among the currently operating cooling units 10 (NO in step S185), the processing of steps S186 and S187 is skipped. Then, the process returns to step S19 in FIG.

  If it is clear that the required number of operating units is frequently changed, the processes in steps S185 to S187 may be omitted.

  Further, although not shown in the flowchart, the controller 9 measures the accumulated operation time of each cooling unit 10. That is, the controller 9 periodically determines the operation state of each cooling unit 10 and updates the corresponding accumulated operation time as needed for the cooling unit 10 in operation. When the cooling unit 10 is changed from the operating state to the stopped state, the controller 9 stops counting the corresponding accumulated operation time.

  The accumulated operation time is typically the accumulated time after the cooling unit 10 is installed. However, when maintenance or the like is performed on the cooling unit 10, the corresponding accumulated operation time is reset (zero clear). ). Further, the accumulated operating time corresponding to any cooling unit 10 may be reset by the user performing a predetermined reset operation on the controller 9. Furthermore, the controller 9 may reset the accumulated operating time of all the cooling units 10 every time a predetermined period elapses. This predetermined cycle may be arbitrarily set, for example, one day, one month, one year, or the like. That is, the cumulative operation time in the present embodiment is not limited to the time measured with reference to the time when the cooling unit 10 is newly installed in the server room 1.

  Note that the processes shown in FIGS. 19 and 22 are generally executed cyclically at a predetermined cycle. However, it may be executed as an event triggered by the absolute value or fluctuation amount of the detection value from the temperature sensor 46 or the current sensor 47 exceeding a predetermined threshold value.

[H. Modified example]
As another method for leveling the cumulative operation time of the cooling unit 10 in the cold standby mode as described above, the following method may be employed.

  (A) Regardless of whether or not the current operating number matches the required operating number, the cooling unit 10 to be operated is switched in a predetermined order every time a predetermined time elapses. Even when the number of operating units needs to be changed, the cooling unit 10 that is activated or stopped in a predetermined priority order is selected. When such a method is adopted, the controller 9 does not need to measure the accumulated operation time.

  (B) Regardless of whether or not the current operation number matches the required operation number, the continuous operation time is counted for each of the cooling units 10 in operation, and the cooling unit 10 whose continuous operation time has reached a certain time is determined. Stop and reset the data of the continuous operation time. When the stopped cooling unit 10 is restarted, the continuous operation time for the cooling unit 10 is newly started. When it is necessary to change the number of operating units, the cooling unit 10 to be started or stopped is selected in a predetermined priority order. When such a method is adopted, the controller 9 stores the continuous operation time instead of the cumulative operation time.

  Further, instead of selecting the cooling unit 10 to be started or stopped so that the cumulative operation time of each cooling unit 10 is leveled, the ratio of the cumulative operation time of each cooling unit 10 becomes a predetermined ratio. Alternatively, the cooling unit 10 to be started or stopped may be selected. For example, for the three cooling units A, B, and C, when it is desired to set the ratio of the cumulative operation time to 1: 2: 3, the ratio is stored in the controller 9 in advance as a ratio set value. Then, every time it is necessary to change the number of operating units, the ratio of the cumulative operating time of the cooling units A, B, and C so far is calculated, and the calculated result is compared with the ratio set value, and the cooling to be operated or stopped is performed. The unit 9 may be selected by the controller 9. Thereby, for example, the high-performance cooling unit 10 having a high energy saving effect can be preferentially operated over the other cooling units 10.

  The processes shown in FIGS. 19 to 22 described above may be executed each time a predetermined time is measured while the controller 9 measures data at any time. Alternatively, the controller 9 determines that detection value data exceeding a predetermined reference value is input from any one of the temperature sensor 46, the current sensor 47, the return air temperature sensor 23, and the supply air temperature sensor 24. May be executed.

[I. Effect]
Next, actions and effects in the air conditioning system SYS according to the present embodiment described above will be listed.

(I-1) Reduction of electric power required for blowing conditioned air In the air conditioning system SYS according to the present embodiment, a relatively large conditioned air outlet 3 can be provided on the side wall surface of the processing target chamber. That is, since the blowout area of the blowout port 3 becomes relatively large, the conditioned air necessary for managing the temperature of the processing target chamber (essentially cooling the information processing equipment accommodated in the rack 4) is secured. There is no need to increase the blowing speed to do this.

  Therefore, it is not necessary to use a blower with a relatively high discharge pressure such as a multi-blade fan (sirocco fan) or a backward-facing fan (turbo fan). Instead, it has a high blowing efficiency such as an axial fan or a plug fan. A fan (specifically, a pressure fan such as a ventilation fan) can be employed. As a result, it is possible to reduce the power required for blowing the conditioned air. Moreover, since such a fan can be reduced in size, space saving can be realized.

  Furthermore, by controlling the blowout speed of conditioned air to a low value, the effect of dynamic pressure (typically, when the discharge pressure of conditioned air is relatively high, an effect similar to an ejector occurs, and a blowout opening is provided. However, the phenomenon that the conditioned air is not blown out and is sucked in reverse) can be reduced.

  In the conventional configuration, when the discharge speed of conditioned air is high, a diffusion plate (so-called baffle plate) for hydrostatic pressure conversion is provided in order to reduce the influence of the dynamic pressure as described above. It was. On the other hand, in the present embodiment, since it is not necessary to provide such a diffusion plate in the vicinity of the discharge port, the structure can be simplified and space saving can be realized, and the pressure associated with the blowing of conditioned air can be achieved. Loss can be reduced and the electric power required for blowing air-conditioned air can be reduced.

  Furthermore, since the conditioned air is supplied from the blowout port 3 on the side wall surface of the processing target chamber, there is no wind direction changing portion such as an elbow or the floor surface blowout port as in the case of supplying the conditioned air from under the conventional floor. , Local pressure loss can be further reduced. Thereby, the electric power required for ventilation of conditioned air can further be reduced.

  Moreover, by reducing the loss related to the blowing of the conditioned air, the blower power loss (heat loss) can be reduced, and thereby the power for regenerating the refrigerant in the heat source portion 200 (electric power required for the refrigeration cycle). Can be reduced.

(I-2) Abolition of underfloor space for air conditioning In the present embodiment, a pair of rack groups are arranged so that their exhaust surfaces face each other, and surround the outer periphery of the pair of rack groups. The shielding plate 5 is arranged and partitioned as a hot aisle for retaining the waste heat air released from the exhaust surface of the rack 4. On the other hand, the other space of the air-conditioning target room (for example, server room 1) is partitioned as a cold aisle for storing conditioned air. By localizing the hot aisle in this way, the space as a cold aisle can be made relatively large.

  Thus, by increasing the proportion of the cold aisle in the processing target chamber, a relatively large conditioned air outlet 3 can be provided on the side wall surface of the processing target chamber. As a result, there is no need to employ a conventional configuration in which conditioned air is blown out from under the floor. That is, an air conditioner such as the cooling unit 10 for generating conditioned air can be arranged at the same floor level as the arrangement floor level of the rack 4. Therefore, unlike the conventional configuration, it is not necessary to provide a space for generating and transporting conditioned air below the floor on which the rack 4 is arranged. In addition, unlike the conventional configuration, it is not necessary to provide a large number of air outlets on the floor surface on which the rack 4 is arranged.

  As a result, it is possible to reduce the number of man-hours required for applying the air conditioning system SYS according to the present embodiment to any one of the air conditioning target rooms. Furthermore, by eliminating the underfloor space, the floor height of the building can be lowered.

(I-3) Reduction of electric power required for the refrigeration cycle in the heat source portion 200 In the server room 1 or the like to which the air conditioning system SYS according to the present embodiment is applied, the variation in seasonal heat load is different from a general office. There are few. That is, information stored in the rack 4 arranged in the server room 1 as compared with the seasonal fluctuation amount of heat entering the server room 1 (for example, depending on a temperature difference between summer and winter). Large heat load from processing equipment. In other words, the influence of outside air on the air-conditioned room is relatively low.

  For this reason, since the cooling heat required for the conditioned air does not fluctuate greatly, it is only necessary to supply a refrigerant having a temperature higher than the dew point temperature of the server room 1 (that is, the temperature at which condensation occurs) from the heat source portion 200 to the cooling unit 10. That is, the temperature of the refrigerant supplied from the heat source portion 200 can be relatively increased. As a result, the operating efficiency of the refrigeration cycle executed by the heat source portion 200 can be increased.

  Moreover, since the supply temperature of the refrigerant can be made relatively high, when the outside air temperature is low, such as in winter, the operation of the refrigeration cycle can be assisted only by dissipating the heat held by the refrigerant into the atmosphere (free cooling). By this free cooling, the power required for the refrigeration cycle of the heat source portion 200 can be reduced.

  Furthermore, as described above, since the water cooling method and the air cooling method can be selected flexibly, the power consumption can be reduced and the degree of freedom in operation can be increased.

(I-4) Efficient discharge of waste heat air In the present embodiment, the pair of rack groups are arranged so that the respective exhaust surfaces face each other and surround the outer periphery of the pair of rack groups. The shielding plate 5 is arranged and partitioned as a hot aisle for retaining the waste heat air released from the exhaust surface of the rack 4. That is, waste hot air is collected locally and circulated through the common return air chamber 8.

  Therefore, the waste air return mechanism can be reduced in size, and the power required to return the waste heat air can be reduced. Further, even when a thermal load is unevenly distributed in a specific portion, the cooling can be easily followed.

(I-5) Operation optimization by blown air volume control In the present embodiment, the temperature of the refrigerant supplied from the heat source portion 200 to the cooling unit 10 is made constant, and then the blown air volume of the conditioned air is controlled. , Adjust the cooling capacity. More specifically, the rotational speed of the fan 16 of the cooling unit 10 is continuously adjusted. Therefore, the cooling capacity can be optimized according to the heat load in the server room 1. Thereby, the electric power concerning the air conditioning of the server room 1 can be reduced.

(I-6) Improvement of maintainability of cooling unit 10 by leveling In the present embodiment, the space associated with the cold aisle in the server room 1 is made relatively large and the cooling associated with each outlet 3 is performed. A plurality of units 10 are used to supply conditioned air in parallel. Therefore, it is possible to adopt a cold standby configuration in which only a part of the plurality of cooling units 10 operates.

  When such a cold standby configuration is adopted, only the specific cooling unit 10 is continuously operated, while the cooling unit 10 may be extremely short in operation time. Such a deviation in operation time may cause the maintenance timing to vary, or the failure probability of the cooling unit 10 having a long operation time to increase. Therefore, in the present embodiment, even when operating in the cold standby mode, the cooling unit 10 to be operated is rotated in a timely manner so that the operation time between the cooling units 10 is leveled.

  Thereby, maintenance can be performed systematically and the failure probability of the cooling unit 10 can be reduced.

(I-7) Improvement of PUE (Power Usage Effectiveness) PUE is the value obtained by dividing the total power consumption of the data center (air conditioning target room) by the power consumption of the information processing equipment. It is one of the indicators shown. According to the present embodiment, PUE can be set to a smaller value by adopting the various characteristic configurations as described above.

(I-8) Improvement of maintainability of fan unit 9A by leveling In this embodiment, a plurality of fan units 9A provided in the vicinity of the suction port 81 are used to exhaust the waste heat air in the hot aisle to the return air chamber 8. To do. Then, the fan unit 9A to be operated is rotated in a timely manner so that the operation time between the fan units 9A is leveled. Thereby, maintenance can be performed systematically and the failure probability of the cooling unit 10 can be reduced.

(I-9) Improvement of cooling efficiency In the air conditioning system of the present embodiment, the hot aisle is partitioned from the cold aisle by the shielding plate 5 at the upper part of the rack 4, and the hot aisle is a space surrounded by the shielding plate 5. Is provided with a suction port 81, and the suction port 81 is provided with a fan unit 9A. The waste heat air discharged from the rack 4 is quickly transported to the return air chamber 8 through the suction port 81 by the fan unit 9A (air blowing unit). Further, the hot aisle air is forcibly exhausted to the return air chamber 8 by the fan unit 9A, so that the hot aisle can be kept at a negative pressure as compared with the cold aisle. Thereby, the flow of the air sent to the hot aisle through the inside of the rack 4 by the conditioned air supplied to the cold aisle can be promoted, and the rack 4 can be cooled reliably.

[J. Example 1 (Power Performance)]
In the air conditioning system SYS according to the present embodiment, an underfloor space for air conditioning is abolished as described in (i-1) above, and a shielding plate is provided above the rack 4 as in (i-8) above. The hot aisle is partitioned from the cold aisle by 5 and the hot aisle, which is the space surrounded by the shielding plate 5, is provided with a suction port 81, and the suction port 81 is provided with a fan unit 9A.

  The air conditioning power required to circulate a constant air volume in the embodiment of such an air conditioning system will be described in comparison with a conventional air conditioning system.

(J1) Schematic configuration of the air conditioning system of the embodiment As shown in FIG. 3, the air conditioning system of the embodiment blows conditioned air 18 from the side wall surface of the server room 1 to the server room 1, and the waste in the server room 1. Hot air is sent to the air conditioning equipment room 7 by the fan unit 9 </ b> A via the suction port 81 and the return air chamber 8.

(J2) Schematic Configuration of Air Conditioning System of Comparative Example As shown in FIG. 23, the air conditioning system of the comparative example is a server via an air supply unit 107 provided on the floor surface (not the side wall surface) of the server room 1. Air-conditioned air 18 is supplied to the room 1. Waste heat air in the server room 1 moves to the air conditioning equipment room 7 via the suction port 81 and the return air chamber 8. The air supply unit 107 is provided with a blade-like member such as a louver blade, and is configured to be able to adjust the blowing pressure of the conditioned air 18 to the server room 1.

  The cooling unit 10A of the comparative example includes a heat exchanger 13A and a dry coil unit including a fan 16A. In addition, since the heat exchanger 13 is designed at a lower wind speed than the heat exchanger 13A, the area (coil area) where the cooling coil is arranged on the surface from which the conditioned air 18 is blown out corresponds to the heat exchanger 13A. It is larger than the surface area.

  Further, in the comparative example, an underfloor air supply chamber 103 is formed under the floor of the server room 1, and a blowout hood 141 for guiding the conditioned air blown out by the cooling unit 10A to the underfloor air supply chamber 103 is provided below the cooling unit 10A. Is provided.

  In the comparative example, the fan unit 9A provided in the vicinity of the suction port 81 of the embodiment is not provided.

(J3) Examination of system Table 1 shows a summary of the power necessary for circulating the static pressure of the system and the constant air volume for the examples and comparative examples.

  Table 1 shows static pressure and information (air conditioner information) such as power necessary for the air conditioner to circulate a constant air volume in the server room 1 for the example and the comparative example.

A. Static pressure In Table 1, static pressure is divided into items and values are shown.

  “1. Main body” means a static pressure in the main body of the cooling unit 10 (or the cooling unit 10A. Hereinafter, both the cooling unit 10 and the cooling unit 10A are appropriately referred to). Among them, the “filter” is a static pressure by a filter provided in the front stage or the rear stage of the fan 16 (or the fan 16A, hereinafter, both of the fan 16 and the fan 16A are appropriately referred to). The “coil” is a static pressure by the dry coil unit 12 (or heat exchanger 13 (or heat exchanger 13A; hereinafter, both the heat exchanger 13 and the heat exchanger 13A are appropriately referred to)). The “casing” is a static pressure generated by the casing of the cooling unit 10.

  In Table 1, the static pressure of the “filter” is the same value in the example and the comparative example, but the static pressure of the “coil” is higher in the comparative example. In FIG. 3, the air that has passed through the heat exchanger 13 is sent out to the front as it is by the fan 16, whereas in FIG. 23, the air that has passed through the heat exchanger 13 </ b> A is guided downward toward the blowing hood 141. by. That is, in the embodiment, air passes from the rear to the front of the heat exchanger 13, whereas in the comparative example, air passes from the rear of the heat exchanger 13A toward the front lower side. Since the heat exchanger 13A has a smaller coil area than the heat exchanger 13, the passing wind speed increases, thereby increasing the pressure loss.

  Also, for the “casing”, the cooling unit 10A of the comparative example has a longer moving distance in the casing than the cooling unit 10 of the embodiment and the direction changes, so the comparative example is more static than the embodiment. The value of is high.

  Depending on the above, in the embodiment, the static pressure in the main body of the cooling unit 10 is 20 mmAq, whereas the static pressure in the comparative example is 40 mmAq.

  “2. Blowing hood” is a static pressure when conditioned air passes through the blowing hood 141. In the comparative example, the static pressure of the blowing hood is 5 mmAq. However, in the example, since the blowing hood 141 does not exist, it is not necessary to consider this static pressure, and the static pressure is 0 mmAq.

  “3. Underfloor chamber” is a static pressure when conditioned air passes through the underfloor air supply chamber 103. Specifically, it means static pressure due to wiring or the like in the underfloor air supply chamber 103. In the comparative example, the static pressure of the underfloor chamber is set to 5 mmAq. However, in the embodiment, since the underfloor air supply chamber 103 does not exist, it is not necessary to consider this static pressure and is set to 0 mmAq.

  “4. Floor outlet” is a static pressure when the conditioned air passes through the air supply unit 107. In the comparative example, the static pressure at the floor outlet is 5 mmAq. However, in the embodiment, since the air supply unit 107 does not exist, it is not necessary to consider this static pressure and is set to 0 mmAq.

  “5. Aisle rack ventilation” is a static pressure when conditioned air passes through the rack 4 in the server room 1. In both the example and the comparative example, the static pressure when passing through the rack 4 is the same, so both static pressures are 5 mmAq.

  “6. Ceiling suction port” is a static pressure when waste heat air passes through the suction port 81. In both the example and the comparative example, the static pressure when the waste heat air passes through the suction port 81 is the same, so both static pressures are 3 mmAq.

  “7. Return air fan casing” is a static pressure when waste heat air passes through a portion of the fan unit 9A shown in FIG. In the embodiment, it is 5 mmAq, but in the comparative example, since the fan unit 9A is not provided, it is not necessary to consider this static pressure, and 0 mmAq.

  “8. Chamber in ceiling” is a static pressure when waste heat air passes through the return air chamber 8. In both the example and the comparative example, the waste heat air that passes through the return air chamber 8 causes a pressure loss due to wiring and beams in the return air chamber 8. However, in the embodiment, the waste heat air is rectified toward the air-conditioning equipment room 7 by the casing of the return air fan 9B and then sent to the return air chamber 8. Therefore, in the comparative example, the static pressure is 5 mmAq, but the static pressure in the example is 4 mmAq which is slightly lower than this.

  “9. In the ceiling to the machine room chamber” is a static pressure when waste heat air passes through the boundary between the return air chamber 8 and the air conditioner room 7. As described above, in the embodiment, compared with the comparative example, the waste heat air is rectified toward the air-conditioning equipment room 7 by the casing of the return air fan 9B and sent out to the return air chamber 8. In this example, the static pressure is 2 mmAq, but the static pressure in the example is 1 mmAq which is slightly lower than this.

B. Power of air-conditioning equipment In both the example and the comparative example, it is assumed that air with an air volume of 309,000 m ³ per hour is circulated in the server room 1.

In the comparative example, air is circulated by the cooling unit 10. That is, the power of the cooling unit 10 introduces conditioned air into the server room 1 and discharges waste heat air into the air conditioning equipment room 7. In the modification, 11 air conditioners were used to circulate. Thereby, the ventilation volume per air conditioner is 28,100 m ³ / h. Considering all the static pressures of the comparative examples shown above, the power of each air conditioner is calculated as 11 kW. This power is calculated according to the following equation (1) with a theoretical efficiency of 0.49. In the formula (1), “6120” is a conversion constant.

{28100 (m ³ / h) / 60 (min / h) × 20 (mmAq)} / {6120 (conversion constant) × 0.49 (efficiency)} ≈11 (kW) (1)
On the other hand, in the embodiment, the introduction of conditioned air into the server room 1 is covered by the power of the cooling unit 10, and the exhaust of waste heat air from the server room 1 to the air conditioning equipment room 7 is driven by the power of the return air fan 9. Be covered. In the example, conditioned air was introduced by 23 cooling units 10, and waste heat air was discharged by 48 return air fans 9. Among the static pressures in Table 1, ~ 4. Corresponds to the introduction of conditioned air into server room 1. ~ 9. Corresponds to the discharge of waste heat air to the air conditioner room 7. For the introduction of 309,000m ³ / h air volume of conditioned air, air volume per one cooling unit 10 becomes 13,435m ³ / h. In addition to the above, 1. ~ 4. In consideration of 20 mmAq, which is the sum of the static pressures, the power of each cooling unit 10 is calculated as 2.2 kW. In this case, the theoretical efficiency is 0.33. Moreover, because of the discharge of the waste heat air air volume of 309,000m ³ / h, the air flow per one return air fan 9 becomes 6,438m ³ / h. In addition to this, the fifth embodiment. ~ 9. In consideration of 18 mmAq, which is the sum of the static pressures, the power of each return air unit 9 is 0.99 kW. In this case, the theoretical efficiency is 0.32.

  From the above, the power required in the embodiment is 98.12 kW which is the sum of the power of the air conditioning unit 10 for 23 units and the power of the return air fan 9 for 48 units.

  Here, when the power required in the example (98.12 kW) and the power required in the comparative example (121. kW) are compared, the ratio is 0.1 in the example when the comparative example is 1.0. 81.

  Depending on the above, according to the embodiment in which the use of the underfloor space for air conditioning is abolished and the fan unit 9A is provided, it can be said that the required power can be reduced to 0.81 times.

  Further, by eliminating the use of the underfloor space for air conditioning, the space under the floor of the server room 1 can be made a dedicated space for wiring. As a result, when using the underfloor space for air conditioning, the height of the underfloor required about 700 mm can be reduced to about 400 mm, and the height of the room used as the server room 1 is increased to about 300 mm. Can do. Alternatively, the floor height of the building can be reduced by 300 mm, which can contribute to a reduction in construction costs.

  In addition, according to the embodiment in which the conditioned air is introduced from the side wall of the server room 1 and the fan unit 9A is provided on the ceiling surface, the followability of the air conditioning temperature with respect to the heat load of the rack 4 can be made better than the comparative example. it can.

[K. Example 2 (Cooling performance)]
Next, the results of evaluating the cooling performance related to the air conditioning system as described above will be described in comparison with a conventional air conditioning system.

(K1) Experimental apparatus FIG. 24 is a diagram schematically showing a configuration of an experimental apparatus for evaluating the air conditioning system according to the embodiment of the present invention. Referring to FIG. 24, as an experimental apparatus, a rack group in which nine racks are arranged in two rows is arranged, and an outlet 3 and a cooling unit 10 communicating with the rack group are provided for the rack group. . Further, it is assumed that a hot aisle and a cold aisle are partitioned for the server rack group. Further, the front door and the rear plate of each rack adopt a mesh structure as shown in FIG.

  The conditioned air supplied from the air outlet 3 is taken in from both sides in the longitudinal direction of the server rack group, and is used for cooling the server device in the rack. The conditioned air (waste heat air) after being used for this cooling is circulated to the air machine room in which the cooling unit 10 is provided through the suction port 81 provided in the ceiling and the air chamber in the back of the ceiling.

Experimental conditions in this experimental apparatus were set as follows.
(1) Air supply temperature (temperature of conditioned air immediately after supply from the air outlet 3): 20 ° C
(2) Supply amount of conditioned air (supply air volume): 18,000 m ³ / h
(3) Width of outlet: 1.6m
(4) Air-conditioning air supply speed (wind speed): 2,0 m / s
(5) Heat load: 3.4 kW / 1 rack × 9 racks × 2 rows (uniform heat load)
(6) Air-conditioning target room area: 65m ²
(K2) Comparison between Actual Measurement Result and Simulation Result Using Experimental Apparatus For the experimental apparatus shown in FIG. 24, as shown in FIG. A temperature sensor was provided at the point, and the temperature measured by each temperature sensor was measured. Further, as a simulation, a method of calculating the temperature distribution by simulating the experimental apparatus shown in FIG. 24 and calculating the airflow three-dimensionally based on the input conditions as described above was adopted. In the experimental apparatus, the temperature sensors were provided 0.2 m from the floor, 1.0 m from the floor, and 1.8 m from the floor. In accordance with this, the temperature distribution on the plane corresponding to each height is also shown for the result of the temperature simulation.

  FIG. 25 is a diagram showing measurement results measured using the experimental apparatus shown in FIG. FIG. 26 is a diagram showing the result of calculating the temperature distribution in the experimental apparatus shown in FIG. 24 by simulation.

  When comparing FIG. 24A to FIG. 24C and FIG. 25A to FIG. 25C, respectively, a part of the temperature obtained by the simulation is slightly higher than the temperature obtained by the experiment. Some are showing low values. However, between the experimental results and the simulation results, the point with the highest temperature (the point closest to the cooling unit near 1.0 m on the floor) coincides with the temperature distribution by the experiment and the simulation as a whole. It can be seen that the temperature distribution by is generally consistent. Therefore, it can be said that the simulation used for the current wind direction has sufficiently high accuracy.

(K3) Simulation relating to wind direction Using the simulation as described above, the inventors of the present application have examined an appropriate wind direction of the air outlet 3 relating to cooling of the server rack. The following cases were assumed as typical cases.

(I) Basic case: The air supply direction is the same as the perpendicular (normal) from the side wall surface to the rack group (the height at which the supply air contacts the rack corresponds to the hot aisle section)
(Ii) Upward case: 45 ° upward / 0 ° left and right, the air supply direction coincides with the normal (normal) from the side wall surface to the rack group (the height at which the air supply contacts the rack is the cold aisle section above the rack group) Equivalent to
(Iii) Diagonally upward case: upper 45 ° / left and right ± 45 °, air supply air direction is ± 45 ° left and right with respect to a perpendicular (normal) from the side wall surface to the rack group (the height at which the air supply contacts the rack is (Equivalent to the cold aisle compartment at the top of the rack group)
Each of these cases is shown in FIG. That is, FIG. 27A shows the positional relationship between the rack group to be simulated and the outlet 3. FIG. 27B shows (1) the supply air direction in the basic case, FIG. 27C shows (2) the supply air direction in the upward case, and FIG. 27D shows (3) the oblique upward direction. Shows the air supply direction in the case.

(K3-1) Basic Case FIG. 28 is a diagram illustrating a simulation result indicating a temperature distribution in the basic case. FIG. 29 is a diagram showing a simulation result showing the wind speed distribution in the basic case. FIG. 30 is a diagram showing a wind speed distribution in each cross section shown in FIG.

  Referring to FIG. 28, it can be seen that at any height, there is a higher temperature portion on the cooling unit side. That is, it can be said that more heat stays on the cooling unit side of the rack group. Further, in the vicinity of 0.2 m above the floor surface (FIG. 28A) and near 1.0 m above the floor surface (FIG. 28B), the heat from the hot aisle to the cold aisle is on the air conditioner side of the rack group. Exudation occurred (total of 3 locations).

  Next, when the wind speed distribution is examined, it can be seen that a separation flow and a stagnation flow are generated in the cold aisle of the rack group on the lower side of the paper, and the wind turbulence is relatively large. Note that the wind velocity distribution was also measured in the above-described experimental apparatus, and the simulation results in FIG. 29 almost coincided with the results measured from the experimental apparatus.

  Also shown is a flow in which a reverse flow is generated from the gap between the rack and the server device accommodated therein, and a part of the waste heat air used for cooling the server device is sucked again.

  As shown in FIG. 30 (a), in the hot aisle of the rack group (cross section A-A in FIG. 29 (a)), the conditioned air rises at a strong speed from the outlet 3 on the cooling unit side where the temperature is high. You can see that Further, as shown in FIG. 30 (b), in the cold aisle of the rack group (cross-section BB in FIG. 29 (b)), the cooling air is flowing below the rack group at a stronger wind speed. Recognize.

  Further, in the rack group on the lower side of the page (cross section D in FIG. 29), the wind speed was distributed with a peak at a position slightly higher than the position where the server apparatus at a point about several tens of centimeters away from the corner of the rack group. . This value was shown to be slightly lower for the absolute value of the wind speed near the corners of the rack group than the experimental results measured from the experimental device, but the tendency for the wind speed to become stronger at the top as the distance from the rack surface increases. Matched.

  Further, in the rack group on the upper side of the page (section F in FIG. 29), the wind speed tended to decrease slightly as the distance from the rack group increased. Furthermore, in the rack group on the upper side of the page (section G in FIG. 29), it is shown that the wind speed of the fourth or fifth rack is stronger than the rack of the suction (3rd) closest to the air outlet 3. ing. This tendency is similar to the experimental results measured from the experimental apparatus.

(K3-2) Upward Case Next, the simulation result of the upward case will be described in comparison with the basic case described above. FIG. 31 is a diagram illustrating a simulation result indicating a temperature distribution in the upward case. FIG. 32 is a diagram showing a simulation result showing an upward wind speed distribution. FIG. 33 is a diagram showing a wind speed distribution in each cross section shown in FIG. 32.

  Referring to FIG. 31, compared to the temperature distribution in the basic case (FIG. 28), the exudation of heat from the hot aisle to the cold aisle was reduced except for the upper side. As a result, the maximum temperature in the rack group decreased from 40 ° C. in the case of the base case to 39 ° C. In particular, it is considered that the temperature on the suction side of the conditioned air in the rack closest to the blower outlet 3 on the upper side of the paper led to a temperature decrease on the exhaust side (hot aisle). Moreover, it was confirmed that the temperature on the suction side of the rack far from the air outlet 3 is maintained at the supply air temperature (22 ° C.), as in the basic case, and a good cooling environment is obtained.

  Moreover, when FIG. 32 and FIG. 33 are seen, compared with a basic case, it turns out that the separation flow and the stagnation flow have decreased. However, the amount of backflow from the gap between the rack and the server device accommodated therein does not change much compared to the basic case.

(K3-3) Diagonally upward case Next, the simulation result of the oblique upward case will be described in comparison with the basic case described above. FIG. 34 is a diagram showing a simulation result showing the temperature distribution in the diagonally upward case. FIG. 35 is a diagram showing a simulation result showing the wind speed distribution obliquely upward. FIG. 36 is a diagram showing a wind speed distribution in each cross section shown in FIG.

  Referring to FIG. 34, compared with the temperature distribution in the basic case (FIG. 28), the exudation of heat from the hot aisle to the cold aisle was reduced except for the upper side. As a result, the maximum temperature in the rack group, which was 40 ° C. in the case of the base case, greatly decreased to 35 ° C. In particular, it is considered that the temperature on the suction side of the conditioned air in the rack closest to the blower outlet 3 on the upper side of the paper led to a temperature decrease on the exhaust side (hot aisle). Moreover, it was confirmed that the temperature on the suction side of the rack far from the air outlet 3 is maintained at the supply air temperature (22 ° C.), as in the basic case, and a good cooling environment is obtained.

  35 and 36, it can be seen that the separation flow and the stagnation flow are reduced as compared with the basic case. Further, it can be seen that the backflow from the gap between the rack and the server device accommodated therein is also reduced compared to the basic case and the upward case.

(K4) Summary As shown in the simulation results of the basic case and the experimental results by the experimental device, the present embodiment shows that the air conditioning system can efficiently cool the entire air conditioning target room. As for the rack in the vicinity, there is a possibility that the intake amount of the conditioned air may be reduced due to the vortex generated in the conditioned air supplied from the outlet 3. Therefore, in the air conditioning system according to the present embodiment, it is preferable that the air outlet 3 is positioned so as to blow out the conditioned air with an inclination of a predetermined non-zero angle with respect to the vertical line from the side wall surface to the rack group.

  In the above-described examples (upward case and diagonally upward case), typically, the configuration in which the conditioned air is discharged by being inclined by 45 ° in the horizontal direction and / or the vertical direction with respect to the vertical line from the side wall surface to the rack group is illustrated. did. In other words, it was confirmed that the air supply air direction of the air outlet 3 was effective to be set to about 45 ° in the upper part and about 45 ° to the left and right from the central axis of the perpendicular.

  However, the present invention is not limited to such a setting, and basically an appropriate wind direction may be set so that no eddy current is generated in the conditioned air around the rack in the vicinity of the air outlet 3. For example, the wind direction in the vertical direction is inclined by 30 ° -60 ° with respect to the horizontal plane, and the wind direction in the left-right direction is 30 ° -60 ° to the left and right with respect to the vertical line from the side wall surface to the rack group. It can be set to tilt only. That is, it is preferable that the conditioned air discharged from the air outlet 3 hits the side surface of the rack surface and does not cause a rapid speed change. In addition, as shown in the upward case described above, the supply air direction from the outlet 3 may be inclined only in one of the vertical direction and the horizontal direction.

[L. Example 3 (Cooling performance)]
Next, a simulation result will be described comparing the cooling performance of the air conditioning system according to the present embodiment with the cooling performance of a conventional air conditioning system.

  FIG. 37 is a plan view showing an arrangement of server rooms (air-conditioning target rooms) that are assumed as application destinations of the air-conditioning system. Referring to FIG. 37, in the comparative study shown below, a configuration is assumed in which rack groups of 10 racks × 2 columns are arranged in an array over 2 columns × 7 rows. Then, these rack groups are divided into three according to the heat load. That is, “rack group 1” (total 60 racks) having a thermal load of 9.00 kW / 1 rack, “rack group 2” (total 100 racks) having a thermal load of 5.00 kW / 1 rack, Assume “rack group 3” (120 racks in total) having a thermal load of 2.25 kW / 1 rack. These positional relationships are as shown in FIG.

  As an air conditioning system according to the present embodiment, assuming a configuration in which conditioned air is supplied from the air outlet 3 provided on the side wall surface as shown in FIG. 2, a conventional air conditioning system as a comparative example is shown in FIG. A configuration is assumed in which conditioned air is supplied to the server room via an air supply unit provided on the floor surface (not the side wall surface) as shown.

  In any of the air conditioning system according to the present embodiment and the conventional air conditioning system, the server rack group of the air conditioning target room is partitioned into hot aisle and cold aisle, there is no black panel in the rack, and the load factor Is 100%.

  In the air conditioning system according to the present embodiment, it is assumed that the supply air temperature (the temperature of the conditioned air immediately after being supplied from air outlet 3) is 20 ° C., and allowable allowable temperature difference Δt is 10 ° C. On the other hand, in the conventional air conditioning system, it is assumed that the supply air temperature (the temperature of the conditioned air immediately after being supplied from the air outlet 3) is 22 ° C. and the allowable temperature rise Δt is 8 ° C. In the conventional air conditioning system, since the conditioned air buffer exists under the floor, the distance between the air supply unit and the cooling unit becomes relatively long, so it is more difficult to lower the air supply temperature. . In this simulation, the supply air temperature is 22 ° C., but is generally 24 ° C. (corresponding to the cold aisle set temperature).

  FIG. 38 is a diagram showing a simulation result of a temperature distribution in a conventional air conditioning system. FIG. 39 is a diagram showing a simulation result of temperature distribution in the air conditioning system according to the present embodiment. FIG. 38 and FIG. 39 show an enlarged view of the high-load rack group (rack group 1) shown in FIG.

  Referring to FIG. 38, in the conventional air conditioning system, even if the original cold aisle set temperature is lowered from 24 ° C. to 22 ° C., the internal temperature of the high load rack is relatively increased. I understand that. Therefore, some local cooling measures are required for such partially heated racks.

  On the other hand, as shown in FIG. 39, in the cooling system according to the present embodiment, the temperature does not increase so much even in a high-load rack, and the overall temperature difference is alleviated. I understand. That is, even if the thermal load is unevenly distributed, the temperature distribution in the entire server room, which is the air-conditioning target room, can be made uniform. As described above, the air conditioning system according to the present embodiment has high followability to the heat load, and can cool the server room more efficiently.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

1 server room, 2 side wall surface, 3 outlets, 4 racks, 5 shielding plates, 7 air conditioning equipment room, 8 return air chamber, 9 controller, 10 cooling unit, 12 dry coil unit, 13 heat exchanger, 14 refrigerant supply port , 15 Refrigerant outlet, 16 fans, 18
Air-conditioned air, 41 Front door, 42 Back plate, 43 Top plate outlet, 44 Cable entry opening, 45 Louver blade, 46, 232, 234 Temperature sensor, 47 Current sensor, 48 shelves, 81 Suction port, 92 Control unit , 94 Data input section, 96 Current data input section, 98 Temperature data input section, 100 Secondary side section, 200 Heat source section, 210 Radiator, 212 Retan header, 214 Supply header, 216 Bypass valve, 218 piping, 220 chiller, 224 out Side piping, 242 return piping, 244 delivery piping, 400 projected image, DEV information processing equipment, SYS air conditioning system.

Claims (11)

An air conditioning system for managing the temperature of an air conditioning target room in which a plurality of racks that accommodate information processing devices are arranged,
A partition for partitioning a first space in contact with the air supply surfaces of the plurality of racks and a second space in contact with the exhaust surfaces of the plurality of racks;
An air conditioning mechanism for supplying conditioned air to the first space;
A return air mechanism for exhausting waste heat air from the second space;
An air outlet for blowing out the air-conditioned air from the air-conditioning mechanism, provided on a side wall surface in the first space of the air-conditioning target room;
The plurality of racks are configured in units of a pair of rack groups arranged adjacently so that the exhaust surfaces face each other.
The partition is
The space located on the exhaust surface side of each of the pair of rack groups is configured to be separated from the other space of the air conditioning target room,
Connecting the second space and an exhaust port provided on a ceiling surface of the air-conditioned room in the second space;
The outlet is provided at a position where the conditioned air is blown out in a direction in which the pair of rack groups extend,
The total value of the width occupied by the outlet in the side wall surface is configured to be larger than the total value of the width generated by projecting the rack group onto the side wall surface,
The return air mechanism is an air conditioning system provided at the exhaust port and including a blower for promoting exhaust of the conditioned air.   The air conditioning system according to claim 1, wherein the air outlet is provided on each of a pair of opposing side wall surfaces.   3. The air conditioning system according to claim 1, wherein the air outlet is positioned so as to blow out the air-conditioned air with an inclination of a non-zero predetermined angle with respect to a vertical line from the side wall surface toward the rack group. The air conditioning mechanism includes a plurality of units arranged in association with the plurality of air outlets,
Each of the plurality of units is
A heat exchanger,
And at least one fan that generates an air flow for heat exchange with the heat exchanger,
The air conditioning system according to any one of claims 1 to 3, wherein the refrigerant supplied to the heat exchanger is maintained at a temperature higher than a dew point temperature of the air conditioning target room. Power consumption detection means for detecting power consumption in the information processing devices in the plurality of racks;
Temperature detecting means for detecting the temperature of waste heat air discharged from the plurality of racks;
Means for calculating a required air conditioning amount of the conditioned air to be supplied to the first space based on the power consumption detected by the power consumption detecting means and the temperature detected by the temperature detecting means;
Means for determining a state in which the plurality of units should operate based on the calculated required air conditioning amount;
The air conditioning system according to claim 4, further comprising control means for controlling operation / stop of the plurality of units in accordance with the determined state to be operated.   The control means controls the operation / stop of the plurality of units under the condition of the calculated number of units that need to be operated so that the cumulative operation period of each unit is leveled. The air conditioning system described in.   The air conditioning system according to any one of claims 4 to 6, wherein the at least one fan is arranged so that a total fan passage area is 50% of an opening area of the blower outlet.   The air conditioning system according to any one of claims 1 to 7, wherein the partition portion includes a plate that continuously exists from at least a part of an upper end of the rack to a ceiling surface of the air conditioning target room.   9. The air conditioning system according to claim 1, wherein the air blowing unit is configured by a plurality of fan units arranged at equal intervals in the air conditioning target room in the second space. Power consumption detection means for detecting power consumption in the information processing devices in the plurality of racks;
Temperature detecting means for detecting the temperature of waste heat air discharged from the plurality of racks;
Means for calculating a necessary air volume for the exhaust from the second space based on the power consumption detected by the power consumption detection means and the temperature detected by the temperature detection means;
Means for determining a state in which the plurality of fan units should be operated based on the calculated required air volume;
9. The air conditioning system according to claim 8, further comprising control means for controlling operation / stop of the plurality of fan units according to the determined state to be operated.   The control means controls the operation / stop of the plurality of fan units under the condition of the calculated number of fan units to be operated so that the cumulative operation period of the fan units is leveled. The air conditioning system according to claim 10.