Server cooling system

Abstract

A server cooling system of the present disclosure comprises: a duct that has a cylindrical shape extending in the up-down direction, and that has an air discharge port formed in an upper part; an exhaust introduction unit that introduces exhaust from a server room to a portion below the air discharge port of the duct; a fan that is provided in the duct and is rotationally driven so that air is discharged from the air discharge port; and a control device. The control device includes: a fan operation unit that causes the fan to rotate from a stopped state when the exhaust is introduced into the duct; and a fan stop unit that causes the fan to stop when a natural circulation condition is satisfied after the fan has rotated.

Description

Server Cooling System

[0001] This disclosure relates to a server cooling system. This application claims priority to Japanese Patent Application No. 2023-181545, filed on October 23, 2023, the contents of which are incorporated herein by reference.

[0002] Servers are sensitive to heat, so if the temperature in a server room remains high for a long time, it can cause problems such as server failure or a shortened lifespan. In order to safely manage servers, it is necessary to control the air conditioning in the server room where the servers are installed and cool the room.

[0003] Patent Document 1 discloses an air conditioning duct system for whole-house heating and cooling of a house. In this air conditioning duct system, a chimney is formed that penetrates from the first floor to the roof and has its upper end protruding onto the roof. Furthermore, a vertical duct is arranged within the chimney.

[0004] Japanese Patent Application Publication No. 7-4732

[0005] When a vertical duct such as that disclosed in Patent Document 1 is used to exhaust air from within a server room, for example, the air inside the duct becomes hotter than the air outside the duct due to the high-temperature exhaust air from within the server room. This makes the air inside the duct lighter than the air outside the duct, creating an upward current within the duct. The air outside the duct is drawn into the duct by the upward current created within the duct. This phenomenon is called the chimney effect. This chimney effect causes the hot air inside the server room to be drawn into the duct and exhausted. However, the exhaust flow rate due to the chimney effect is small, and it has been thought that the server room cannot be sufficiently cooled.

[0006] The present disclosure has been made to solve the above-mentioned problems, and aims to provide a server cooling system that can ensure sufficient cooling performance.

[0007] In order to solve the above problems, the server cooling system of the present disclosure comprises a duct that is cylindrical and extends in the vertical direction and has an air exhaust port formed at the top, an exhaust intake section that introduces exhaust air from a server room into a section of the duct below the air exhaust port, a fan that is provided in the duct and is driven to rotate so that air is exhausted from the air exhaust port, and a control device, wherein the control device has a fan operating section that rotates the fan from a stopped state when the exhaust air is introduced into the duct, and a fan stopping section that stops the fan when natural circulation conditions are met after the fan has rotated.

[0008] The server cooling system according to the present disclosure comprises a duct having a cylindrical shape extending in the vertical direction, with an air inlet formed at the bottom and an air outlet formed at the top, a refrigerant introduction section between the air inlet and the air outlet in the duct that introduces circulating refrigerant from a server room, a fan provided in the duct and driven to rotate so that air is discharged from the air outlet, and a control device, wherein the refrigerant introduction section has a heat exchange section disposed within the duct that performs heat exchange between the circulating refrigerant and the air within the duct, and the control device has a fan operation section that rotates the fan from a stopped state when the circulating refrigerant is introduced into the duct, and a fan stop section that stops the fan when natural circulation conditions are met after the fan has rotated.

[0009] According to the server cooling system of the present disclosure, sufficient cooling performance can be ensured.

[0010] FIG. 1 is a configuration diagram of a server cooling system according to a first embodiment of the present disclosure. FIG. 2 is a perspective view illustrating the overall shape of a duct according to the first embodiment of the present disclosure. FIG. 3 is a functional block diagram of a control device according to the first embodiment of the present disclosure. FIG. 4 is a flowchart illustrating an operation procedure of the server cooling system according to the first embodiment of the present disclosure. FIG. 5 is a diagram illustrating time variations in exhaust flow path and duct temperature according to the first embodiment of the present disclosure. FIG. 6 is a configuration diagram of a server cooling system according to a second embodiment of the present disclosure. FIG. 7 is a functional block diagram of a control device according to the second embodiment of the present disclosure. FIG. 8 is a flowchart illustrating an operation procedure of the server cooling system according to the second embodiment of the present disclosure. FIG. 9 is a configuration diagram of a refrigerant introduction section according to a modified example of the second embodiment of the present disclosure. FIG. 10 is a configuration diagram of a server cooling system according to a third embodiment of the present disclosure. FIG. 11 is a flowchart illustrating an operation procedure of the server cooling system according to the third embodiment of the present disclosure. FIG. 12 is a configuration diagram of a server cooling system according to a modified example of the third embodiment of the present disclosure. FIG. 13 is a configuration diagram of a server cooling system according to another embodiment of the present disclosure. FIG. 14 is a configuration diagram of a server cooling system according to another embodiment of the present disclosure. FIG. 15 is a cross-sectional view along the horizontal plane of a duct according to another embodiment of the present disclosure. FIG. 16 is a configuration diagram of a server cooling system according to another embodiment of the present disclosure.

[0011] First Embodiment (Configuration of Server Cooling System) A server cooling system 100 according to a first embodiment of the present disclosure will be described below with reference to FIGS. 1 to 5. In FIGS. 1 and 2, air flow is indicated by arrows. Servers 2 are installed in a server room 1. The servers 2 generate heat during operation. The heat from the servers 2 causes the temperature inside the server room 1 to rise. The server cooling system 100 is used to cool the server room 1. As shown in FIG. 1, the server cooling system 100 includes a duct 10, an exhaust air intake 20, a fan 3, a damper 30, a temperature sensor 4, a control device 40, and a display 5. An air intake 1b is formed in the server room 1. Air from outside the server room 1 is supplied to the server room 1 through the air intake 1b. The high-temperature air inside the server room 1 heated by the servers 2 is exhausted through the exhaust air intake 20 and duct 10, which will be described later.

[0012] (Duct) The duct 10 has a cylindrical shape extending in the vertical direction Dv. The duct 10 is disposed along the sidewall 1a of the server room 1, which extends in the vertical direction Dv. The length of the duct 10 can be changed as appropriate. However, the length of the duct 10 is preferably, for example, 1 m or more and 500 m or less. In this embodiment, the lower end of the duct 10 is closed. An air exhaust port 11 is formed at the upper part of the duct 10. The duct 10 has a first cylindrical portion 10a and a second cylindrical portion 10b. The first cylindrical portion 10a extends in the vertical direction Dv along the sidewall 1a of the server room 1. The second cylindrical portion 10b is provided at the upper end of the first cylindrical portion 10a. The second cylindrical portion 10b is connected to the first cylindrical portion 10a. The second cylindrical portion 10b extends upward from the upper end of the first cylindrical portion 10a. The second cylindrical portion 10b extends upward so as to gradually move away from the side wall 1a in the horizontal direction. The second cylindrical portion 10b has an opening at the end opposite the first cylindrical portion 10a. This opening is the air exhaust port 11 of the duct 10. The air exhaust port 11 faces slightly downward. In other words, the opening direction of the air exhaust port 11 has a downward direction component.

[0013] The duct 10 has a fan exhaust port 12 in the second cylindrical portion 10b. The fan exhaust port 12 is provided separately from the air exhaust port 11 and faces the side wall 1a of the server room 1. The fan exhaust port 12 is provided to penetrate the duct 10 and connects the inside and outside of the duct 10. Multiple fan exhaust ports 12 (four in this embodiment) are arranged horizontally.

[0014] (Exhaust Air Intake Portion) The exhaust air intake portion 20 extends from inside the server room 1 to the first tubular portion 10a of the duct 10. The exhaust air intake portion 20 is a pipe that penetrates the side wall 1a of the server room 1. The exhaust air intake portion 20 introduces high-temperature exhaust air from the server room 1 into a portion of the duct 10 below the air outlet 11. In this embodiment, the exhaust air intake portion 20 is formed in a tubular shape that extends horizontally. As shown in FIG. 2 , multiple exhaust air intake portions 20 (four in this embodiment) are arranged horizontally. The exhaust air intake portions 20 are in communication with the duct 10.

[0015] (Fans) The fans 3 are provided in the second cylindrical portion 10b of the duct 10. The fans 3 are arranged so as to face the side wall 1a of the server room 1. The fans 3 are attached to each fan exhaust port 12, and multiple fans (four in this embodiment) are arranged horizontally. The fans 3 are driven to rotate so that air is exhausted from the air exhaust port 11.

[0016] (Damper) The damper 30 is provided at the air exhaust port 11 and opens and closes the air exhaust port 11. Here, if the state in which the damper 30 opens the air exhaust port 11 is referred to as an open state, and the state in which the damper 30 closes the air exhaust port 11 is referred to as a closed state, in Figure 1, the open state of the damper 30 is illustrated by a solid line, and the closed state of the damper 30 is illustrated by a dashed line.

[0017] (Temperature Sensor) The temperature sensor 4 detects the temperature inside the duct 10. The temperature sensor 4 is attached to the inner surface of the first cylindrical portion 10a of the duct 10.

[0018] (Control Device) The control device 40 is electrically connected to the server 2, the fan 3, the damper 30, and the temperature sensor 4. As shown in Fig. 3 , the control device 40 has functional units, including an acquisition unit 41, a determination unit 42, a fan operation unit 43, a fan stop unit 44, a damper closing unit 45, and a damper opening unit 46.

[0019] The acquisition unit 41 acquires information from the outside. For example, the acquisition unit 41 acquires information on whether the server 2 is operating. The acquisition unit 41 also acquires the temperature inside the duct 10 detected by the temperature sensor 4.

[0020] The determination unit 42 determines whether or not the natural circulation condition is satisfied. The natural circulation condition is a condition in which air can naturally circulate through the duct 10 at a volume sufficient to cool the servers 2, solely due to the chimney effect caused by the temperature inside the duct 10 being higher than the temperature outside the duct 10. In this embodiment, the determination unit 42 determines that the natural circulation condition is satisfied when the temperature detected by the temperature sensor 4 exceeds a predetermined threshold.

[0021] The fan operating unit 43 starts the fan 3 from a stopped state when exhaust air is introduced into the duct 10. The fan operating unit 43 can also adjust the rotation speed of the fan 3 to adjust the exhaust flow rate by the fan 3. The fan stopping unit 44 stops the fan 3 when the natural circulation condition is satisfied after the fan 3 has started rotating.

[0022] The damper closing unit 45 operates the damper 30 to close the air exhaust port 11, for example, before the fan 3 starts to rotate. The damper opening unit 46 operates the damper 30 to open the air exhaust port 11, for example, after the fan 3 has rotated.

[0023] (Display Unit) The display unit 5 is connected to the control device 40. The display unit 5 displays the status of the server cooling system 100 in real time. Examples of information displayed on the display unit 5 include the temperature of the duct 10 detected by the temperature sensor 4 and the volume of air flowing through the duct 10. In this embodiment, the exhaust flow rate due to the fan 3 and the exhaust flow rate due to the chimney effect are displayed separately.

[0024] (Operation of the Server Cooling System) Next, the operation procedure of the server cooling system 100 will be described with reference to the flow chart of FIG. 4 . When the servers 2 start operating, the heat from the servers 2 raises the room temperature in the server room 1. Then, high-temperature exhaust air is introduced from the server room 1 into the duct 10. The acquisition unit 41 acquires information that the servers 2 are operating (step S11). Immediately after step S11, or after a predetermined time has elapsed, the damper closing unit 45 operates the damper 30 to close the air outlet 11 (step S12). Immediately thereafter, the fan operation unit 43 rotates the fan 3, which is currently stopped (step S13). As the fan 3 rotates, high-temperature air in the server room 1 is introduced into the duct 10. The high-temperature exhaust air introduced into the duct 10 is exhausted outside the server room 1 through the fan outlet 12. In this way, immediately after the servers 2 start operating, the high-temperature air in the server room 1 is forcibly exhausted by the fan 3.

[0025] Here, the time changes in the exhaust flow rate and temperature of the duct 10 from step S13 are as shown in Figure 5. The horizontal axis of Figure 5 represents elapsed time, and the vertical axis of Figure 5 represents the temperature of the duct 10 or the exhaust flow rate of the duct 10. In Figure 5, the temperature of the duct 10 is shown by a solid line. Also in Figure 5, the exhaust flow rate by the fan 3 is shown by a dashed line, and the exhaust flow rate due to the chimney effect is shown by a dashed line. The time changes in the exhaust flow rate and temperature of the duct 10 as shown in Figure 5 are displayed on the display unit 5, for example.

[0026] In this embodiment, the exhaust flow rate by the fan 3 is controlled while monitoring the indoor temperature of the duct 10. When the fan 3 starts to rotate, the exhaust flow rate by the fan 3 increases rapidly, as shown in Fig. 5. This increases the exhaust flow rate sent from the server room 1 to the duct 10, and the temperature inside the duct 10 rises. When the temperature inside the duct 10 rises, an upward flow due to thermal convection occurs inside the duct 10, and the exhaust flow rate of the duct 10 increases (chimney effect).

[0027] When a predetermined time has elapsed since the start of rotation of the fan 3, the rotation speed of the fan 3 is reduced. As a result, the exhaust flow rate by the fan 3 gradually decreases. Furthermore, as the temperature rises, the damper opening unit 46 operates the damper 30 to gradually increase the opening of the air exhaust port 11 (step S14). As a result, the exhaust flow rate due to the chimney effect gradually increases. In this way, forced exhaust by the fan 3 and natural exhaust due to the chimney effect are used together, and the proportion of natural exhaust due to the chimney effect increases over time.

[0028] Thereafter, the determination unit 42 determines whether the natural circulation condition, in which a volume of air sufficient to cool the servers 2 can naturally circulate through the duct 10 by the chimney effect alone, is satisfied (step S15). In this embodiment, the temperature inside the duct 10 becomes a substantially constant value (e.g., 40°C) over time. The determination unit 42 uses this constant temperature inside the duct 10 as a threshold, and determines that the natural circulation condition is satisfied when the temperature detected by the temperature sensor 4 exceeds a predetermined threshold. This threshold can be changed as appropriate depending on the conditions.

[0029] If the natural circulation condition is met (step S15; YES), the damper opening unit 46 operates the damper 30 to completely open the air exhaust port 11 (step S16). Thereafter, the fan stopping unit 44 stops the fan 3 (step S17). Step S17 completely switches from forced exhaust by the fan 3 to natural exhaust by the chimney effect. After step S17, the high-temperature air in the server room 1 is exhausted by the natural circulation of air in the duct 10 due to the chimney effect. This cools the server room 1, and the room temperature in the server room 1 is kept constant. The cooling system operates according to the above procedure.

[0030] The operating procedure of the server cooling system 100 can be modified as appropriate. For example, steps S12 and S13 may be performed simultaneously. Also, steps S16 and S17 may be performed simultaneously.

[0031] (Operation and Effect) In this embodiment, the server cooling system 100 includes a duct 10, an exhaust air introduction section 20, a fan 3, and a control device 40. The duct 10 has a cylindrical shape extending in the vertical direction Dv. An air exhaust port 11 is formed at the top of the duct 10. The exhaust air introduction section 20 is provided in a portion of the duct 10 below the air exhaust port 11. The exhaust air introduction section 20 introduces exhaust air from the server room 1. The fan 3 is provided in the duct 10. The fan 3 is driven to rotate so that air is exhausted from the air exhaust port 11. The control device 40 includes a fan operation section 43 and a fan stop section 44. The fan operation section 43 rotates the fan 3 from a stopped state when exhaust air from the server room 1 is introduced into the duct 10. The fan stop section 44 stops the fan 3 when a natural circulation condition is met after the fan 3 has rotated.

[0032] According to the above configuration, when high-temperature exhaust air from the server room 1 is introduced into the duct 10, the control device 40 rotates the fan 3, which is normally stopped. As a result, for a while after the start of exhaust, the air in the server room 1 is forcibly exhausted by the blowing force of the fan 3. Because high-temperature exhaust air from the server room 1 is supplied into the duct 10, the temperature inside the duct 10 becomes higher than the temperature outside the duct 10. This causes an upward flow inside the duct 10. This upward flow draws the air in the server room 1 into the duct 10. This phenomenon is called the chimney effect. Immediately after the start of exhaust, the exhaust flow rate due to the chimney effect is low, but the fan 3 forcibly supplies a large amount of high-temperature exhaust air into the duct 10. This causes the temperature in the duct 10 to rise rapidly, increasing the exhaust flow rate due to the chimney effect. After that, the server room 1 is sufficiently exhausted solely by the exhaust flow rate due to the chimney effect. The conditions under which this state occurs are referred to as natural circulation conditions. In this embodiment, when this natural circulation condition is met, the control device 40 stops the fan 3. As a result, the high-temperature air in the server room 1 is sufficiently exhausted solely by the chimney effect, and the server room 1 is sufficiently cooled. Therefore, according to this embodiment, it is possible to ensure sufficient cooling performance by utilizing the natural circulation of air due to the chimney effect.

[0033] In this embodiment, the server cooling system 100 further includes a temperature sensor 4 that detects the temperature inside the duct 10. The control device 40 has a determination unit 42 that determines whether the natural circulation condition is satisfied. The determination unit 42 determines that the natural circulation condition is satisfied when the temperature detected by the temperature sensor 4 exceeds a predetermined threshold.

[0034] This allows the determination unit 42 to determine whether or not the natural circulation condition is satisfied from the temperature of the duct 10. This allows the control device 40 to accurately determine whether or not the natural circulation condition is satisfied.

[0035] It is not necessary to provide the temperature sensor 4. In this case, for example, the determination unit 42 may determine that the natural circulation condition is satisfied when a predetermined time has elapsed since the fan 3 started to rotate.

[0036] In this case, the determination unit 42 can determine whether the natural circulation condition is met from the time that has elapsed since the fan 3 started rotating. This eliminates the need to provide a separate device for determining whether the natural circulation condition is met, thereby simplifying the configuration of the server cooling system 100.

[0037] In this embodiment, the server cooling system 100 further includes a damper 30 that opens and closes the air exhaust port 11. The duct 10 further includes a fan exhaust port 12 that is provided separately from the air exhaust port 11. A fan 3 is attached to the fan exhaust port 12. The control device 40 further includes a damper closing unit 45 and a damper opening unit 46. The damper closing unit 45 operates the damper 30 to close the air exhaust port 11 before the fan 3 starts to rotate. The damper opening unit 46 operates the damper 30 to open the air exhaust port 11 after the fan 3 has rotated.

[0038] As a result, when the fan 3 is rotating, the server cooling system 100 can exhaust air from the duct 10 using the fan exhaust port 12, in which the fan 3 is installed, as the main exhaust port. Therefore, the server cooling system 100 can efficiently exhaust air using the fan 3. Furthermore, after the exhaust flow rate has increased sufficiently due to the chimney effect, the fan 3 is stopped, the air exhaust port 11 is opened, and air from the duct 10 is exhausted from both the fan exhaust port 12 and the air exhaust port 11. Therefore, when the fan 3 is stopped, the server cooling system 100 can increase the opening area of ​​the exhaust port and increase the exhaust flow rate. Therefore, according to this embodiment, the server cooling system 100 can efficiently exhaust air from the duct 10 according to the timing, further improving the cooling efficiency of the server cooling system 100.

[0039] In this embodiment, the duct 10 includes a first cylindrical portion 10a extending in the vertical direction Dv and a second cylindrical portion 10b provided at the upper end of the first cylindrical portion 10a and communicating with the first cylindrical portion 10a. The second cylindrical portion 10b extends upward, gradually moving away from the side wall 1a in the horizontal direction. The second cylindrical portion 10b has an air outlet 11 at the end opposite the first cylindrical portion 10a. The second cylindrical portion 10b is curved so that the air outlet 11 faces slightly downward. This prevents rainwater and other contaminants from entering the duct 10 through the air outlet 11.

[0040] Second Embodiment (Configuration of Server Cooling System) A server cooling system 200 according to a second embodiment of the present disclosure will be described below with reference to Figures 6 to 8. Configurations similar to those in the previously described embodiment will be designated by the same names and reference numerals, and descriptions thereof will be omitted as appropriate. In Figure 6, in addition to the flow of air, the flow of circulating refrigerant R, which will be described later, is indicated by arrows.

[0041] In this embodiment, in addition to the intake port 1b, an exhaust port 1c is formed in the server room 1. The exhaust port 1c exhausts high-temperature air from within the server room 1 to the outside of the server room 1.

[0042] Furthermore, the duct 10 has an air inlet 13 formed at its lower part in addition to the air outlet 11 formed at its upper part. The air inlet 13 is provided at the lower end of the first cylindrical part 10a of the duct 10. The air inlet 13 penetrates the first cylindrical part 10a in the up-down direction Dv. The air inlet 13 supplies outside air into the duct 10. The air introduced into the duct 10 from the air inlet 13 is discharged to the outside of the duct 10 through the air outlet 11.

[0043] (Refrigerant Introduction Section) The server cooling system 200 also includes a refrigerant introduction section 50 instead of the exhaust air introduction section 20. The refrigerant introduction section 50 introduces the circulating refrigerant R from the server room 1 between the air inlet 13 and the air outlet 11 in the vertical direction Dv. The circulating refrigerant R absorbs heat in the server room 1 and is then supplied into the duct 10. The circulating refrigerant R is supplied into the duct 10 after directly exchanging heat with the servers 2, for example.

[0044] The refrigerant introduction section 50 has a heat exchange section 51, a refrigerant supply pipe 52, and a refrigerant discharge pipe 53. The heat exchange section 51 is disposed within the duct 10 to perform heat exchange between the circulating refrigerant R and the air within the duct 10. In this embodiment, the heat exchange section 51 is disposed within the first cylindrical section 10a of the duct 10.

[0045] The refrigerant supply pipe 52 extends horizontally from within the server room 1 and is connected to the heat exchanger 51. The refrigerant supply pipe 52 penetrates the side wall 1a of the server room 1 and the first cylindrical portion 10a of the duct 10. The refrigerant supply pipe 52 supplies the circulating refrigerant R that has absorbed heat from the server room 1 to the heat exchanger 51. The refrigerant discharge pipe 53 extends horizontally from the heat exchanger 51 and into the server room 1. The refrigerant discharge pipe 53 penetrates the side wall 1a of the server room 1 and the first cylindrical portion 10a of the duct 10. The refrigerant discharge pipe 53 returns the circulating refrigerant R that has been cooled by exchanging heat with the air inside the servers 2 in the heat exchanger 51 to the server room 1. The circulating refrigerant R returned from the refrigerant discharge pipe 53 to the server room 1 again absorbs heat from the server room 1 and is then supplied to the heat exchanger 51 through the refrigerant supply pipe 52.

[0046] 7 , the control device 40 further includes, as a functional unit, a refrigerant operation unit 47. The refrigerant operation unit 47 operates the refrigerant introduction unit 50 to introduce the circulating refrigerant R into the duct 10. In addition, the fan operation unit 43 of this embodiment rotates the fan 3 from a stopped state when the circulating refrigerant R is introduced into the duct 10.

[0047] (Operation of the Server Cooling System) Next, the operation procedure of the server cooling system 200 will be described with reference to the flow chart of FIG. 8 . When the server 2 starts operating, the heat from the server 2 raises the room temperature of the server room 1. The acquisition unit 41 acquires information about the operation of the server 2 (step S21). Immediately after step S21, the refrigerant operation unit 47 operates the refrigerant introduction unit 50 to introduce the circulating refrigerant R into the duct 10 (step S22). Immediately thereafter, or after a predetermined time has elapsed, the damper closing unit 45 operates the damper 30 to close the air outlet 11 (step S23). Immediately thereafter, the fan operation unit 43 rotates the stopped fan 3 (step S24). As the fan 3 rotates, outside air is introduced into the duct 10 through the air inlet 13. The air introduced into the duct 10 is exhausted through the fan outlet 12. In this way, immediately after the server 2 starts operating, the air in the duct 10 is forcibly exhausted by the fan 3. The outside air introduced into the duct 10 cools the circulating refrigerant R introduced into the duct 10 by the refrigerant introduction part 50. The circulating refrigerant R cooled in the duct 10 is returned into the server room 1.

[0048] The heat transferred from the circulating refrigerant R increases the exhaust flow rate sent from the server room 1 to the duct 10, raising the temperature inside the duct 10. When the temperature inside the duct 10 rises, an upward flow occurs inside the duct 10 due to thermal convection, increasing the exhaust flow rate of the duct 10 (chimney effect).

[0049] In this embodiment, the exhaust flow rate by the fan 3 is also controlled while monitoring the indoor temperature of the duct 10. When a predetermined time has elapsed since the fan 3 started rotating, the rotation speed of the fan 3 is reduced. As a result, the exhaust flow rate by the fan 3 gradually decreases. Furthermore, as the temperature rises, the damper opening unit 46 operates the damper 30 to gradually increase the opening of the air exhaust port 11 (step S25). As a result, the exhaust flow rate due to the chimney effect gradually increases. In this way, forced exhaust by the fan 3 and natural exhaust due to the chimney effect are used together, and the proportion of natural exhaust due to the chimney effect increases over time.

[0050] Thereafter, the determination unit 42 determines whether or not the natural circulation condition, which means that a volume of air sufficient to cool the server 2 can naturally circulate through the duct 10 by the chimney effect alone, is satisfied (step S26). In this embodiment, as in the first embodiment, the determination unit 42 determines that the natural circulation condition is satisfied when the temperature detected by the temperature sensor 4 exceeds a predetermined threshold value.

[0051] If the natural conditions are met (step S26; YES), the damper opening unit 46 operates the damper 30 to completely open the air outlet 11 (step S27). Thereafter, the fan stopping unit 44 stops the fan 3 (step S28). Step S28 completely switches from forced exhaust by the fan 3 to natural exhaust by the chimney effect. After step S28, fresh air continues to be supplied to the duct 10 due to the natural circulation of air within the duct 10 caused by the chimney effect. This allows the circulating refrigerant that has absorbed heat from the server room 1 to be sufficiently cooled within the duct 10. The circulating refrigerant R cooled within the duct 10 is returned to the server room 1, cooling the server room 1. This maintains a constant room temperature in the server room 1. The cooling system operates according to the above procedure.

[0052] The operation procedure of the server cooling system 200 can be changed as appropriate. For example, steps S23 and S24 may be performed simultaneously. Also, steps S27 and S28 may be performed simultaneously.

[0053] (Operation and Effect) In this embodiment, the server cooling system 200 includes a duct 10, a refrigerant introduction unit 50, a fan 3, and a control device 40. The duct 10 has a cylindrical shape extending in the vertical direction Dv. An air inlet 13 is formed at the bottom of the duct 10, and an air outlet 11 is formed at the top of the duct 10. The refrigerant introduction unit 50 introduces circulating refrigerant R from the server room 1 between the air inlet 13 and the air outlet 11 in the duct 10. The refrigerant introduction unit 50 includes a heat exchange unit 51 disposed within the duct 10 to perform heat exchange between the circulating refrigerant R and the air within the duct 10. The fan 3 is provided in the duct 10. The fan 3 is rotationally driven to discharge air from the air outlet 11. The control device 40 includes a fan operation unit 43 and a fan stop unit 44. The fan operating unit 43 starts rotating the fan 3 from a stopped state when the circulating refrigerant R is introduced into the duct 10. The fan stopping unit 44 stops the fan 3 when the natural circulation condition is satisfied after the fan 3 has started rotating.

[0054] According to the above configuration, when high-temperature circulating refrigerant is introduced from the server room 1 into the duct 10, the control device 40 rotates the fan 3, which is normally stopped. As a result, the duct 10 can be forcibly exhausted by the airflow of the fan 3 for a while after the start of exhaust. The circulating refrigerant R is supplied into the duct 10 while recovering heat from the server room 1. The refrigerant supplied into the duct 10 supplies heat to the air in the duct 10 via the heat exchanger 51. This heat heats the air in the duct 10, making the air inside the duct 10 hotter than the air outside the duct 10. This creates an upward flow in the duct 10. This upward flow draws the air in the server room 1 into the duct 10 (chimney effect). Immediately after the start of exhaust, the exhaust flow rate due to the chimney effect is low, but the heat of the circulating refrigerant R heats the inside of the duct 10, causing the temperature of the duct 10 to rise rapidly. This increases the exhaust flow rate due to the chimney effect. Thereafter, the air is sufficiently exhausted from the duct 10 solely by the exhaust flow rate due to the chimney effect, and the natural circulation condition is met. In this embodiment, when this natural circulation condition is met, the control device 40 stops the fan 3. This allows the air in the duct 10 to be sufficiently exhausted solely by the chimney effect. This allows efficient heat exchange between the circulating refrigerant R and the air, and the server room 1 can be sufficiently cooled by the air flowing through the duct 10 via the circulating refrigerant R. Therefore, according to this embodiment, it is ultimately possible to ensure sufficient cooling performance by utilizing the natural circulation of air due to the chimney effect.

[0055] 9 , the refrigerant introduction section 50 may further include fins 57 provided on the outer surface of the heat exchange section 51. Specifically, the refrigerant introduction section 50 includes a supply-side header 54, a discharge-side header 55, a connecting pipe 56, and the fins 57.

[0056] The supply-side header 54 is connected to the refrigerant supply pipe 52. The circulating refrigerant is supplied to the supply-side header 54. The discharge-side header 55 is connected to the refrigerant discharge pipe 53. The discharge-side header 55 discharges the circulating refrigerant R, which has been cooled by exchanging heat with the air in the duct 10 in the heat exchange section 51, into the refrigerant discharge pipe 53.

[0057] The connecting pipe 56 connects the supply-side header 54 and the discharge-side header 55. A plurality of connecting pipes 56 are provided. The fins 57 are attached so as to protrude from the outer circumferential surface of the connecting pipe 56. The fins 57 are formed in a plate shape. A plurality of fins 57 are provided. Each fin 57 is attached so as to be penetrated by a plurality of connecting pipes 56.

[0058] As described above, in this modification, the refrigerant introduction section 50 further includes fins 57 provided on the outer surface of the heat exchange section 51 .

[0059] As a result, the fins 57 increase the surface area of ​​the heat exchanger 51, thereby improving the heat exchange efficiency of the heat exchanger 51. As a result, the cooling performance of the server cooling system 100 is further improved.

[0060] Also, in this embodiment, similarly to the first embodiment, the temperature sensor 4 may not be provided. In this case, the determination unit 42 may determine that the natural circulation condition is satisfied when a predetermined time has elapsed since the fan 3 started to rotate.

[0061] Third Embodiment (Configuration of Server Cooling System) A server cooling system 300 according to a third embodiment of the present disclosure will be described below with reference to Figures 10 and 11. Configurations similar to those in the above-described embodiments will be designated by the same names and reference numerals, and descriptions thereof will be omitted as appropriate. In Figure 10, in addition to the flow of air, the flow of circulating refrigerant R, which will be described later, is indicated by arrows.

[0062] 10 , the lower end of the first cylindrical portion 10a of the duct 10 is closed, as in the first embodiment. The server cooling system 300 of this embodiment includes the exhaust gas inlet 20 of the first embodiment and the refrigerant inlet 50 of the second embodiment. The refrigerant inlet 50 is provided below the exhaust gas inlet 20. As in the second embodiment, the refrigerant inlet 50 supplies the circulating refrigerant R that has absorbed heat from the server room 1 into the duct 10, and exchanges heat with the air in the duct 10 in the heat exchanger 51.

[0063] The circulating refrigerant R supplied into the duct 10 is cooled by absorbing heat into the air inside the duct 10. It is then returned to the server room 1. If the circulating refrigerant R is not sufficiently cooled inside the duct 10, the refrigerant discharge pipe 53 may be connected to a separate heat exchanger (not shown) such as a chiller to further cool the circulating refrigerant R.

[0064] The fan operating unit 43 of this embodiment starts rotating the fan 3 from a stopped state when exhaust air from the server room 1 is introduced into the duct 10 and the circulating refrigerant R is introduced into the duct 10 .

[0065] (Operation of the Server Cooling System) Next, the operation procedure of the server cooling system 300 will be described with reference to the flow chart of FIG. 11 . When the servers 2 are operating, the heat from the servers 2 raises the room temperature in the server room 1. Then, high-temperature exhaust air is introduced from the server room 1 into the duct 10. The acquisition unit 41 acquires information about the operation of the servers 2 (step S31). Immediately after step S31, the refrigerant operation unit 47 operates the refrigerant introduction unit 50 to introduce the circulating refrigerant into the duct 10 (step S32). Immediately thereafter, or after a predetermined time has elapsed, the damper closing unit 45 operates the damper 30 to close the air outlet 11 (step S33). Immediately thereafter, the fan operation unit 43 rotates the fan 3, which has been stopped (step S34). The rotation of the fan 3 introduces high-temperature air from within the server room 1 into the duct 10. The high-temperature exhaust air introduced into the duct 10 is exhausted to the outside of the server room 1 through the fan outlet 12. In this way, immediately after the servers 2 start operating, the high-temperature air in the server room 1 is forcibly exhausted by the fans 3 .

[0066] In this embodiment, the exhaust flow rate by the fan 3 is also controlled while monitoring the indoor temperature of the duct 10. When the fan 3 starts to rotate, the exhaust flow rate sent from the server room 1 to the duct 10 increases, causing the temperature inside the duct 10 to rise. In addition, circulating refrigerant R that has absorbed heat from the server room 1 is supplied into the duct 10. The air inside the duct 10 is heated by the circulating refrigerant R from the server room 1, causing the temperature inside the duct 10 to rise further.

[0067] When the temperature inside the duct 10 rises, an upward flow occurs inside the duct 10 due to thermal convection, and the exhaust flow rate of the duct 10 increases (chimney effect).

[0068] When a predetermined time has elapsed since the start of rotation of the fan 3, the rotation speed of the fan 3 is reduced. As a result, the exhaust flow rate by the fan 3 gradually decreases. Furthermore, as the temperature rises, the damper opening unit 46 operates the damper 30 to gradually increase the opening of the air exhaust port 11 (step S35). As a result, the exhaust flow rate due to the chimney effect gradually increases. In this way, forced exhaust by the fan 3 and natural exhaust due to the chimney effect are used together, and the proportion of natural exhaust due to the chimney effect increases over time.

[0069] When a predetermined time has elapsed since the start of rotation of the fan 3, the rotation speed of the fan 3 is reduced. As a result, the exhaust flow rate by the fan 3 gradually decreases. Furthermore, as the temperature rises, the damper opening unit 46 operates the damper 30 to gradually increase the opening of the air exhaust port 11 (step S35). As a result, the exhaust flow rate due to the chimney effect gradually increases. In this way, forced exhaust by the fan 3 and natural exhaust due to the chimney effect are used together, and the proportion of natural exhaust due to the chimney effect increases over time.

[0070] Thereafter, the determination unit 42 determines whether or not the natural circulation condition, which means that a volume of air sufficient to cool the server 2 can naturally circulate through the duct 10 by the chimney effect alone, is satisfied (step S37). In this embodiment, as in the first embodiment, the determination unit 42 determines that the natural circulation condition is satisfied when the temperature detected by the temperature sensor 4 exceeds a predetermined threshold value.

[0071] If the natural conditions are met (step S37; YES), the damper opening unit 46 operates the damper 30 to completely open the air exhaust port 11 (step S37). Thereafter, the fan stopping unit 44 stops the fan 3 (step S38). Step S38 completely switches from forced exhaust by the fan 3 to natural exhaust by the chimney effect. After step S38, the high-temperature air in the server room 1 is exhausted by the natural circulation of air in the duct 10 due to the chimney effect. This cools the server room 1, and the room temperature in the server room 1 is kept constant. The cooling system operates according to the above procedure.

[0072] The operating procedure of the server cooling system 300 can be changed as appropriate. For example, steps S33 and S34 may be performed simultaneously. Also, steps S37 and S38 may be performed simultaneously.

[0073] (Operation and Effect) In this embodiment, the server cooling system 300 further includes a refrigerant introduction unit 50. The refrigerant introduction unit 50 introduces the circulating refrigerant R from the server room 1 into the duct 10 below the air outlet 11. The refrigerant introduction unit 50 has a heat exchange unit 51. The heat exchange unit 51 is disposed within the duct 10 and performs heat exchange between the circulating refrigerant R and the air within the duct 10. The fan operation unit 43 starts the fan 3 from a stopped state when exhaust air from the server room 1 is introduced into the duct 10 and the circulating refrigerant R is introduced into the duct 10.

[0074] As a result, the circulating refrigerant R is supplied into the duct 10 while collecting heat from within the server room 1. The circulating refrigerant R supplied into the duct 10 supplies heat to the air within the duct 10 via the heat exchanger 51. This heat further heats the air within the duct 10, increasing the exhaust flow rate due to the chimney effect. This makes it possible to exhaust a larger amount of high-temperature air from within the duct 10, further improving cooling performance.

[0075] As shown in FIG. 12 , the server cooling system 300 may further include a first earthquake-resistant member 6 and a second earthquake-resistant member 7 .

[0076] The first earthquake-resistant member 6 is provided at the connection between the exhaust inlet 20 and the side wall 1a of the server room 1. The first earthquake-resistant member 6 is, for example, a rubber damper attached to the outer circumferential surface of the exhaust inlet 20. When the first earthquake-resistant member 6 contracts, it can absorb vibrations transmitted to the duct 10 via the side wall 1a.

[0077] The second earthquake-resistant member 7 is provided at the connection between the refrigerant inlet 50 and the side wall 1a of the server room 1. The second earthquake-resistant member 7 is, for example, a rubber damper attached to the outer circumferential surface of the refrigerant supply pipe 52 and the outer circumferential surface of the refrigerant discharge pipe 53. By contracting, the second earthquake-resistant member 7 can absorb vibrations transmitted to the duct 10 via, for example, the side wall 1a. In this way, even if the duct 10 is installed away from the side wall 1a of the server room 1, the first earthquake-resistant member 6 and the second earthquake-resistant member 7 can absorb vibrations of the duct 10, ensuring the earthquake resistance of the duct 10. Note that the first earthquake-resistant member 6 and the second earthquake-resistant member 7 are not limited to rubber dampers. For example, the first earthquake-resistant member 6 and the second earthquake-resistant member 7 may be configured to absorb vibrations using a bellows structure.

[0078] The above-described first earthquake-resistant members 6 are applicable to the server cooling system 100 of the first embodiment. The second earthquake-resistant members 7 are applicable to the server cooling system 200 of the second embodiment.

[0079] Also, in this embodiment, similarly to the first embodiment, the temperature sensor 4 may not be provided. In this case, the determination unit 42 may determine that the natural circulation condition is satisfied when a predetermined time has elapsed since the fan 3 started to rotate.

[0080] Also in this embodiment, similarly to the second embodiment, the heat exchange section 51 of the refrigerant introduction section 50 may have fins 57 on its outer peripheral surface. That is, the heat exchange section 51 may have a supply-side header 54, a discharge-side header 55, a connecting pipe 56, and fins 57.

[0081] (Other Embodiments) Although the embodiments of the present disclosure have been described in detail above with reference to the drawings, the specific configuration is not limited to this embodiment, and design changes and the like within the scope that does not deviate from the gist of the present disclosure are also included.

[0082] 13 , the server cooling system 100 may further include a heat insulating material 8. The heat insulating material 8 is provided on a side surface 10 c of the outer circumferential surface of the duct 10 that faces away from the side wall 1 a of the server room 1.

[0083] The heat insulating material 8 prevents the air inside the duct 10 from radiating heat to the outside of the duct 10. This prevents a decrease in the temperature of the air inside the duct 10. Therefore, according to this embodiment, the server cooling system 100 can prevent a decrease in the exhaust flow rate due to the chimney effect.

[0084] The location of the heat insulating material 8 can be changed as appropriate. For example, the heat insulating material 8 may be provided around the entire outer periphery of the first cylindrical portion 10a of the duct 10. Alternatively, the heat insulating material 8 may be provided on the inner surface of the duct 10.

[0085] 14, the server cooling system 100 may further include a heating mechanism 60. The heating mechanism 60 is provided on a side surface 10c of the outer circumferential surface of the duct 10 that faces away from the side wall 1a of the server room 1. The heating mechanism 60 heats the air inside the duct 10. The heating mechanism 60 is, for example, an absorber 61 that absorbs sunlight.

[0086] The heating mechanism 60 heats the air in the duct 10. This prevents a decrease in the temperature of the air in the duct 10. Therefore, according to this embodiment, the server cooling system 100 can prevent a decrease in the exhaust flow rate due to the chimney effect. Furthermore, the heating mechanism 60 in this modified example is an absorber 61 that absorbs sunlight. Therefore, the air in the duct 10 can be heated by the energy of sunlight.

[0087] 15, the side surface 10c of the duct 10 on which the absorber 61 is installed is curved. This makes it possible to increase the surface area of ​​the absorber 61 compared to when the side surface 10c is flat. Therefore, the absorber 61 can absorb more sunlight.

[0088] The location where the absorbent material 61 is installed can be changed as appropriate. For example, the absorbent material 61 may be provided around the entire outer periphery of the first cylindrical portion 10a of the duct 10. Also, a heater may be provided as the heating mechanism 60 instead of the absorbent material 61. Also, this heater may be installed inside the duct 10, for example.

[0089] 16 , the server cooling system 100 may further include a solar panel 9. The solar panel 9 is provided on a side surface 10c of the outer periphery of the duct 10 that faces away from the side wall 1a of the server room 1. The solar panel 9 converts sunlight irradiated from outside the duct 10 into electricity and supplies the electricity to the fans 3.

[0090] This allows the server cooling system 100 to generate at least a portion of the power required to operate the fans 3 using solar power generation.

[0091] Furthermore, the side surface 10c of the duct 10 on which the solar panel 9 is installed may be curved as shown in Figure 15. In this case, the surface area of ​​the solar panel 9 increases, thereby increasing the amount of power generated by the solar panel 9. Furthermore, the installation location of the solar panel 9 can be changed as appropriate. For example, the solar panel 9 may be provided around the entire outer periphery of the first cylindrical portion 10a of the duct 10.

[0092] The heat insulating material 8, the heating mechanism 60, and the solar panel 9 described above can be applied not only to the server cooling system 100 of the first embodiment, but also to the server cooling systems 200 and 300 of the second and third embodiments.

[0093] In the above embodiments, the server cooling systems 100, 200, and 300 are described as including the damper 30, but this is not limitative. The server cooling systems 100, 200, and 300 do not necessarily have to include the damper 30.

[0094] (Hardware Configuration) The control device 40 of each of the above-described embodiments and modifications is implemented in a computer 1100 shown in Fig. 17. The computer 1100 includes a processor 1110, a main memory 1120, a storage 1130, and an interface 1140.

[0095] The operations of the above-described processing units of the control device 40 are stored in the form of a program in the storage 1130. The processor 1110 reads the program from the storage 1130, loads it into the main memory 1120, and executes the above-described processing in accordance with the program. The processor 1110 also allocates storage areas in the main memory 1120 corresponding to the above-described storage units in accordance with the program.

[0096] The program may be for realizing some of the functions to be performed by the computer 1100. For example, the program may be combined with other programs already stored in the storage 1130 or other programs implemented in other devices to perform the functions. Furthermore, the computer 1100 may include a custom large-scale integrated circuit (LSI) such as a programmable logic device (PLD) in addition to or instead of the above configuration. Examples of PLDs include programmable array logic (PAL), generic array logic (GAL), complex programmable logic device (CPLD), and field programmable gate array (FPGA). In this case, some or all of the functions realized by the processor 1110 may be realized by the integrated circuit.

[0097] Examples of storage 1130 include a magnetic disk, a magneto-optical disk, and a semiconductor memory. Storage 1130 may be an internal medium directly connected to the bus of computer 1100, or an external medium connected to computer 1100 via interface 1140 or a communication line. Furthermore, when this program is distributed to computer 1100 via a communication line, computer 1100 that receives the program may load the program into main memory 1120 and execute the above-mentioned processing. Storage 1130 may also be a non-transitory tangible storage medium.

[0098] The program may also be a program for realizing part of the above-described functions. Furthermore, the program may be a so-called differential file (differential program) that realizes the above-described functions in combination with another program already stored in storage 1130.

[0099] <Additional Notes> The server cooling systems 100, 200, and 300 described in the respective embodiments can be understood, for example, as follows.

[0100] (1) The server cooling system 100, 300 according to the first aspect comprises a duct 10 having a cylindrical shape extending in the vertical direction Dv and having an air exhaust port 11 formed at the top thereof, an exhaust intake section 20 for introducing exhaust air from a server room 1 into a section of the duct 10 below the air exhaust port 11, a fan 3 provided in the duct 10 and driven to rotate so that air is exhausted from the air exhaust port 11, and a control device 40, wherein the control device 40 has a fan operating section 43 for rotating the fan 3 from a stopped state when the exhaust air is introduced into the duct 10, and a fan stopping section 44 for stopping the fan 3 when a natural circulation condition is met after the fan 3 has rotated.

[0101] According to the above configuration, when high-temperature exhaust air from the server room 1 is introduced into the duct 10, the control device 40 rotates the fan 3, which is normally stopped. Because high-temperature exhaust air from the server room 1 is supplied into the duct 10, the temperature inside the duct 10 becomes higher than the temperature outside the duct 10. This generates an upward flow within the duct 10. This upward flow draws air from the server room 1 into the duct 10. This phenomenon is called the chimney effect. Immediately after the start of exhaust, the exhaust flow rate due to the chimney effect is low, but the fan 3 forcibly supplies a large amount of high-temperature exhaust air into the duct 10. This causes the temperature of the duct 10 to rise rapidly, increasing the exhaust flow rate due to the chimney effect. Thereafter, sufficient air is exhausted from the server room 1 solely through the exhaust flow rate due to the chimney effect. The conditions under which this state occurs are referred to as natural circulation conditions. In this embodiment, when this natural circulation condition is met, the control device 40 stops the fan 3. As a result, the high-temperature air in the server room 1 is sufficiently exhausted solely through the chimney effect, thereby sufficiently cooling the server room 1.

[0102] (2) The server cooling system 100, 300 of the second aspect may be the server cooling system 100, 300 of the first aspect, further comprising a first earthquake-resistant member 6 that is provided at the connection between the exhaust intake section 20 and the server room 1 and is capable of absorbing vibrations.

[0103] This allows the first earthquake-resistant member 6 to absorb vibrations transmitted to the duct 10 when an earthquake occurs, for example.

[0104] (3) A third aspect of the server cooling system 300 is the server cooling system 300 of the first or second aspect, and further includes a refrigerant introduction section 50 below the air exhaust port 11 in the duct 10 for introducing circulating refrigerant R from the server room 1, and the refrigerant introduction section 50 has a heat exchange section 51 arranged in the duct 10 for performing heat exchange between the circulating refrigerant R and the air in the duct 10, and the fan operating section 43 may rotate the fan 3 from a stopped state when the exhaust air is introduced into the duct 10 and the circulating refrigerant R is introduced into the duct 10.

[0105] As a result, the circulating refrigerant R is supplied into the duct 10 while collecting heat from within the server room 1. The circulating refrigerant R supplied into the duct 10 supplies heat to the air within the duct 10 via the heat exchanger 51. This heat further heats the air within the duct 10, increasing the exhaust flow rate due to the chimney effect.

[0106] (4) A server cooling system 200 according to a fourth aspect includes a duct 10 having a cylindrical shape extending in the vertical direction Dv, an air inlet 13 formed at the bottom, and an air outlet 11 formed at the top, a refrigerant introduction section 50 for introducing circulating refrigerant R from a server room 1 between the air inlet 13 and the air outlet 11 in the duct 10, a fan 3 provided in the duct 10 and driven to rotate so that air is discharged from the air outlet 11, and a control device 40, wherein the refrigerant introduction section 50 has a heat exchange section 51 disposed within the duct 10 for exchanging heat between the circulating refrigerant R and the air within the duct 10, and the control device 40 has a fan operating section 43 for rotating the fan 3 from a stopped state when the circulating refrigerant R is introduced into the duct 10, and a fan stopping section 44 for stopping the fan 3 when a natural circulation condition is satisfied after the fan 3 has rotated.

[0107] According to the above configuration, when high-temperature circulating refrigerant R is introduced into the duct 10 from the server room 1, the control device 40 rotates the fan 3, which is normally stopped. The circulating refrigerant R is supplied into the duct 10 after collecting heat from the server room 1. The refrigerant supplied into the duct 10 supplies heat to the air in the duct 10 via the heat exchanger 51. This heat heats the air in the duct 10, making the air inside the duct 10 hotter than the air outside the duct 10. This creates an upward flow in the duct 10. This upward flow draws the air in the server room 1 into the duct 10 (chimney effect). Immediately after exhaust begins, the exhaust flow rate due to the chimney effect is low, but the heat from the circulating refrigerant R heats the inside of the duct 10, causing the temperature of the duct 10 to rise rapidly. This increases the exhaust flow rate due to the chimney effect. Thereafter, sufficient air is exhausted from the duct 10 solely through the exhaust flow rate due to the chimney effect, satisfying the natural circulation condition. In this embodiment, when this natural circulation condition is met, the control device 40 stops the fan 3. As a result, the air in the duct 10 is sufficiently exhausted solely by the chimney effect. This allows efficient heat exchange between the circulating refrigerant R and the air, and the interior of the server room 1 can be sufficiently cooled by the air flowing through the duct 10 via the circulating refrigerant R.

[0108] (5) The server cooling system 200, 300 of the fifth aspect is the server cooling system 200, 300 of the third or fourth aspect, and the refrigerant introduction section 50 may further have fins 57 provided on the outer surface of the heat exchange section 51.

[0109] As a result, the fins 57 increase the surface area of ​​the heat exchanger 51, thereby improving the heat exchange efficiency of the heat exchanger 51.

[0110] (6) The server cooling system 200, 300 of the sixth aspect may be any one of the server cooling systems 200, 300 of the third to fifth aspects, and may further include a second earthquake-resistant member 7 that is provided at the connection between the refrigerant introduction part 50 and the server room 1 and is capable of absorbing vibrations.

[0111] This allows the second earthquake-resistant member 7 to absorb vibrations transmitted to the duct 10 when an earthquake occurs, for example.

[0112] (7) A seventh aspect of the server cooling system 100, 200, 300 is a server cooling system 100, 200, 300 of any one of the first to sixth aspects, further comprising a temperature sensor 4 that detects the temperature inside the duct 10, and the control device 40 has a judgment unit 42 that judges whether the natural circulation condition is satisfied, and the judgment unit 42 may judge that the natural circulation condition is satisfied when the temperature detected by the temperature sensor 4 exceeds a predetermined threshold value.

[0113] This allows the determination unit 42 to determine whether the natural circulation condition is satisfied from the temperature of the duct 10.

[0114] (8) The server cooling system 100, 200, 300 of an eighth aspect is the server cooling system 100, 200, 300 of any one of the first to sixth aspects, wherein the control device 40 has a judgment unit 42 that judges whether the natural circulation condition is satisfied, and the judgment unit 42 may judge that the natural circulation condition is satisfied when a predetermined time has elapsed since the fan 3 started to rotate.

[0115] This allows the determination unit 42 to determine whether the natural circulation condition is satisfied based on the time that has passed since the fan 3 started to rotate.

[0116] (9) A ninth aspect of the server cooling system 100, 200, 300 is the server cooling system 100, 200, 300 of any one of the first to eighth aspects, further comprising a damper 30 that opens and closes the air exhaust port 11, the duct 10 is provided separately from the air exhaust port 11, and further comprises a fan exhaust port 12 to which the fan 3 is attached, and the control device 40 may further comprise a damper closing unit 45 that operates the damper 30 to close the air exhaust port 11 before the fan 3 starts to rotate, and a damper opening unit 46 that operates the damper 30 to open the air exhaust port 11 after the fan 3 has rotated.

[0117] As a result, when the fan 3 is rotating, the server cooling system 100 can exhaust air from the duct 10 using the fan exhaust port 12, in which the fan 3 is installed, as the main exhaust port. Therefore, the server cooling system 100 can efficiently exhaust air using the fan 3. Furthermore, after the exhaust flow rate has increased sufficiently due to the chimney effect, the fan 3 is stopped, the air exhaust port 11 is opened, and the air from the duct 10 is exhausted from both the fan exhaust port 12 and the air exhaust port 11. Therefore, when the fan 3 is stopped, the server cooling system 100 can increase the opening area of ​​the exhaust port and increase the exhaust flow rate.

[0118] (10) The server cooling system 100 , 200 , 300 of a tenth aspect is the server cooling system 100 , 200 , 300 of any one of the first to ninth aspects, and may further include a heat insulating material 8 provided in the duct 10 .

[0119] The heat insulating material 8 prevents the air in the duct 10 from radiating heat to the outside of the duct 10. This prevents the temperature of the air in the duct 10 from decreasing.

[0120] (11) The server cooling system 100, 200, 300 of the eleventh aspect may be any one of the server cooling systems 100, 200, 300 of the first to tenth aspects, and may further include a heating mechanism 60 provided in the duct 10 to heat the air in the duct 10.

[0121] The heating mechanism 60 heats the air in the duct 10. This prevents the temperature of the air in the duct 10 from decreasing.

[0122] (12) A server cooling system 100, 200, 300 according to a twelfth aspect is a server cooling system 100, 200, 300 according to any one of the first to eleventh aspects, further comprising a solar panel 9 provided in the duct 10 for converting sunlight irradiated from outside the duct 10 into electricity, and the solar panel 9 may supply electricity to the fan 3.

[0123] This allows the server cooling system 100 to generate at least a portion of the power required to operate the fans 3 using solar power generation.

[0124] According to the server cooling system of the present disclosure, sufficient cooling performance can be ensured.

[0125] DESCRIPTION OF SYMBOLS 1...Server room 1a...Side wall 1b...Air intake port 1c...Exhaust port 2...Server 3...Fan 4...Temperature sensor 5...Display unit 6...First earthquake-resistant member 7...Second earthquake-resistant member 8...Insulating material 9...Solar panel 10...Duct 10a...First cylindrical portion 10b...Second cylindrical portion 10c...Side surface 11...Air exhaust port 12...Fan exhaust port 13...Air inlet 20...Exhaust air introduction section 30...Damper 40...Control device 41...Acquisition section 42...Determination section 43...Fan operation section 44...Fan stopping section 45...Damper closing section 46...Damper opening section 47...Refrigerant operation section 50...Refrigerant introduction section 51...Heat exchange section 52...Refrigerant supply pipe 53...Refrigerant discharge pipe 54...Supply side header 55...Discharge side header 56...Connecting pipe 57...Fin 60...Heating mechanism 61: Absorbent material 100: Server cooling system 200: Server cooling system 300: Server cooling system 1100: Computer 1110: Processor 1120: Main memory 1130: Storage 1140: Interface Dv: Up-down direction

Claims

1. A server cooling system comprising: a duct in the shape of a cylinder extending in the vertical direction and with an air exhaust port formed at the upper part; an exhaust intake section which introduces exhaust air from a server room into a section of the duct below the air exhaust port; a fan which is provided in the duct and driven to rotate so that air is exhausted from the air exhaust port; and a control device, wherein the control device has: a fan operating section which causes the fan to rotate from a stopped state when the exhaust air is introduced into the duct; and a fan stopping section which stops the fan when natural circulation conditions are satisfied after the fan has rotated.

2. The server cooling system according to claim 1, further comprising a first earthquake-resistant member provided at a connection between said exhaust intake section and said server room and capable of absorbing vibrations.

3. The server cooling system of claim 1, further comprising a refrigerant inlet section below the air exhaust port in the duct for introducing circulating refrigerant from the server room, the refrigerant inlet section having a heat exchange section disposed within the duct for performing heat exchange between the circulating refrigerant and the air within the duct, and the fan operating section causing the fan to rotate from a stopped state when the exhaust air is introduced into the duct and the circulating refrigerant is introduced into the duct.

4. A server cooling system comprising: a duct having a cylindrical shape extending in the vertical direction, with an air inlet formed at the bottom and an air outlet formed at the top; a refrigerant inlet section for introducing circulating refrigerant from a server room between the air inlet and the air outlet in the duct; a fan provided in the duct and driven to rotate so as to exhaust air from the air outlet; and a control device, wherein the refrigerant inlet section has a heat exchange section disposed within the duct for exchanging heat between the circulating refrigerant and the air within the duct, and the control device has: a fan operating section for rotating the fan from a stopped state when the circulating refrigerant is introduced into the duct; and a fan stopping section for stopping the fan when natural circulation conditions are satisfied after the fan has rotated.

5. A server cooling system according to claim 3 or 4, wherein the coolant introduction section further has fins provided on an outer surface of the heat exchange section.

6. A server cooling system according to claim 3 or 4, further comprising a second earthquake-resistant member provided at a connection between the coolant introduction section and the server room and capable of absorbing vibrations.

7. A server cooling system as described in any one of claims 1 to 4, further comprising a temperature sensor for detecting the temperature inside the duct, wherein the control device has a judgment unit for judging whether the natural circulation condition is satisfied, and wherein the judgment unit judges that the natural circulation condition is satisfied when the temperature detected by the temperature sensor exceeds a predetermined threshold value.

8. A server cooling system as described in any one of claims 1 to 4, wherein the control device has a judgment unit that judges whether the natural circulation condition is satisfied, and the judgment unit judges that the natural circulation condition is satisfied when a predetermined time has elapsed since the fan started to rotate.

9. A server cooling system as described in any one of claims 1 to 4, further comprising a damper for opening and closing the air exhaust port, the duct further having a fan exhaust port provided separately from the air exhaust port and having the fan attached thereto, and the control device further comprising: a damper closing section for operating the damper to close the air exhaust port before the fan begins to rotate, and a damper opening section for operating the damper to open the air exhaust port after the fan has rotated.

10. A server cooling system according to any one of claims 1 to 4, further comprising a thermal insulation material provided in the duct.

11. The server cooling system according to any one of claims 1 to 4, further comprising a heating mechanism provided in the duct for heating air within the duct.

12. A server cooling system as described in any one of claims 1 to 4, further comprising a solar panel provided in the duct for converting sunlight irradiated from outside the duct into electricity, the solar panel supplying power to the fan.

Images