JPWO2013186904A1 - Condensation detection device, cooling system, and cooling medium flow rate control method - Google Patents

Abstract

The supply conduit (14) for supplying the cooling medium from the cooling medium supply device (12) to the cooled device (10) is provided with a dew condensation detector (20) for detecting water droplets due to dew condensation and detecting dew condensation. The heat transfer unit (30) is connected to the dew condensation detector (20) and the cooled device ( Heat is transferred to the cooling medium flowing through the supply line (14) to and from 10).

Description

  The embodiment relates to a dew condensation detection apparatus that detects dew condensation by detecting water droplets generated by dew condensation.

  When the temperature of the electronic device component becomes a temperature equal to or lower than the dew point temperature of the surrounding atmosphere, dew condensation occurs on the electronic device component. Moisture generated by condensation may cause corrosion of metal parts of the electronic device or cause short circuit between electrodes of the electric circuit inside the electronic device, which may cause problems due to condensation.

  In general, the temperature and humidity of the installation environment of the liquid-cooled electronic device and the temperature of the coolant are managed so that no condensation occurs. However, if the air conditioner breaks down or a temperature abnormality of the coolant output device occurs, the temperature of the coolant reaching the electronic device may become lower than the dew point, and the inside of the electronic device may be in a dew condensation state. In such a state, the electronic device may be turned on or the electronic device may continue to operate. In this case, if there is more than a certain amount of water droplets due to condensation inside the electronic device, a short circuit between the electrodes may occur in the electric circuit in the electronic device, which may cause failures such as malfunction of the electric circuit or burning of the electric circuit. is there.

In order to prevent such problems due to condensation, it has been proposed to provide a condensation sensor in an electronic device to detect condensation and take measures against condensation. That is, when dew condensation is detected by the dew condensation sensor, the electronic device is prohibited from being turned on or the electronic device is dried.
There are several types of condensation sensors. There is known a dew condensation water detection sensor that detects dew condensation by detecting that water droplets generated by condensation flow out and reach a detection unit. Such a dew condensation water detection sensor generally has a device to be measured and a water drop sensor (liquid sensor) formed of metal or the like that easily causes dew condensation. The measured object is provided in a cold water supply passage between the cold water supply device and the electronic device, and is cooled by the cold water from the cold water supply device. Therefore, when the temperature of the object to be measured becomes lower than the dew point temperature of the atmosphere, condensation occurs on the object to be measured. That is, the cold water from the cold water supply device first cools the measurement object of the dew condensation detection sensor, and then the cold water is supplied to the electronic device to cool the heat generating components in the electronic device.

  Since the heat capacity of the subject body of the condensed water detection sensor is small and does not generate heat, the temperature of the cold water entering the electronic device after cooling the subject body is the temperature of the cold water supplied to the subject body from the cold water supply device. Almost the same as temperature. Therefore, when dew condensation occurs on the side body, dew condensation may occur in the cold water passage in the electronic device almost simultaneously.

  Here, it has been proposed to prevent condensation in the apparatus by reducing the flow rate of the supplied refrigerant and increasing the refrigerant temperature when dew condensation is detected by a dew condensation sensor provided in the external refrigerant facility piping. (For example, refer to Patent Document 1).

  In addition, it has been proposed that a dew condensation sensor is provided in the uppermost stream of a supply side pipe that supplies cold water to a cooling panel to detect dew condensation and control a cold water supply device (see, for example, Patent Document 2).

JP 2006-32515 A Japanese Patent No. 3447257

  Here, as described above, since the dew condensation sensor detects dew condensation by detecting water droplets due to dew condensation, a certain amount of time is required from the start of dew condensation until it reaches a detectable amount of water droplets due to dew condensation. Therefore, there is a possibility that water droplets may be generated due to condensation in the electronic device between the time when condensation starts in the condensation sensor and the electronic device and until the condensation sensor detects condensation. May cause this. Therefore, there is a demand for the development of a dew condensation detection device that can prevent dew condensation from occurring in an electronic device between the start of dew condensation in the dew condensation sensor and the time when the dew condensation sensor detects dew condensation.

  According to one embodiment, a dew condensation detector that is provided in a supply pipeline that supplies a cooling medium from a cooling medium supply device to a cooled device and detects water droplets due to condensation to detect dew condensation; and A heat transfer unit configured to transfer heat from the cooling medium flowing through the reflux pipe returning the cooling medium to the cooling medium supply apparatus to the cooling medium flowing through the supply pipe between the dew condensation detector and the apparatus to be cooled; A condensation detection device is provided.

  In addition, a cooled device that cools internal components with a cooling medium, a cooling medium supply device that generates a cooling medium to be supplied to the cooled device, the cooled device and the cooling medium supply device are connected, and the cooling A circulation line for connecting a cooling medium from the medium supply apparatus to the cooled apparatus, the cooled apparatus and the cooling medium supply apparatus, and returning the cooling medium from the cooled apparatus to the cooling medium supply apparatus A conduit, a dew condensation detector provided in the middle of the supply conduit, and heat of the cooling medium flowing through the reflux conduit through the supply conduit between the condensation detector and the cooled device A cooling system is provided having a heat transfer section that is moved to a cooling medium.

  Further, a cooling medium flow rate control method for controlling the flow rate of the cooling medium supplied to the cooled apparatus, wherein the temperature of the cooling medium discharged from the cooled apparatus is detected, and the detected temperature is compared with a temperature threshold value. There is provided a cooling medium flow rate control method for controlling the flow rate of the cooling medium supplied to the apparatus to be cooled based on the comparison result.

  According to the embodiment, since the cooling water having a temperature higher than that in the dew condensation detector is supplied to the electronic device, dew condensation occurs in the dew condensation detector earlier than in the electronic device. As a result, the dew condensation detector can detect the dew condensation before the dew condensation occurs inside the electronic device, and it is possible to prevent problems caused by the dew condensation in the electronic device.

It is the schematic which shows the whole structure of the electronic device cooling system with which the dew condensation detection apparatus by 1st Embodiment was attached. It is an expanded sectional view of an example of a heat transfer part. It is an expanded sectional view of other examples of a heat transfer part. It is a flowchart of a dew condensation detection process. It is the schematic which shows the whole structure of the electronic device cooling system with which the dew condensation detection apparatus by 2nd Embodiment was attached. It is an expanded sectional view of the A section in FIG. It is a perspective view of connection piping. It is sectional drawing which shows the modification of connection piping. It is a flowchart of the cold water flow rate control process which adjusts the supply amount of cold water. It is the schematic which shows the whole structure of the electronic device cooling system with which the dew condensation detection apparatus by 3rd Embodiment was attached. It is a flowchart of the cold water flow control process performed with the electronic device cooling system shown in FIG. It is a time chart which shows the operation | movement of each part at the time of the cold water flow rate control process shown in FIG. 11, and the change of temperature.

  Next, embodiments will be described with reference to the drawings.

  FIG. 1 is a schematic diagram showing an overall configuration of an electronic device cooling system to which a dew condensation detection device according to the first embodiment is attached.

  In FIG. 1, an electronic device 10 that is an example of a cooled device is a liquid-cooled electronic device such as a computer or a server, for example, and is cooled by low-temperature cooling water (hereinafter referred to as cold water) supplied from a cold water supply device 12. The internal heat generating components (for example, semiconductor devices and power supply circuits) are cooled. The cold water generated by the cold water supply device 12 is supplied to a cooling water passage (not shown) in the electronic device 10 through the cold water supply pipe 14. A heat generating component is arranged in the middle of the cooling water passage, and the cold water absorbs heat from the heat generating component and cools the heat generating component. Cooling water (hereinafter referred to as hot water) that has been heated by cooling the heat generating components is returned from the cooling water passage in the electronic device 10 to the cold water supply device 12 through the hot water recirculation conduit 16.

  The cold water supply device 12 is a well-known cooling water cooling device having, for example, a refrigerator and a heat exchanger, but any device that can cool the hot water discharged from the electronic device 10 and supply it to the electronic device 10 again as cold water. Any configuration of the cooling water cooling device may be used.

  In this embodiment, the cooling water is used as the cooling medium. However, the cooling medium is not limited to the cooling water, and may be a cooling medium such as a cooling liquid other than water.

  Normally, the cold water supply device 12 cools the hot water flowing from the hot water circulation pipe 16 to a predetermined temperature to make cold water, and flows the cold water to the cold water supply pipe 14 at a constant flow rate. Therefore, the cold water supply device 12 is provided with a water temperature sensor 12a for detecting the temperature of the hot water flowing from the hot water circulation pipe 16 and a water temperature sensor 12b for detecting the temperature of the cold water supplied to the cold water supply pipe 14. Yes. Further, the cold water supply device 12 is provided with a flow rate controller 12 c that adjusts the flow rate of the cold water supplied to the cold water supply line 14. The flow rate controller 12c may be a flow rate adjustment valve provided in the flow path of cold water, or may be a mechanism that adjusts the flow rate by adjusting the number of rotations of a pump for transporting cold water.

  The cold water supply device 12 is provided with a control unit 12d for controlling the flow rate controller 12c based on the detected temperatures of the water temperature sensors 12a and 12b. The control unit 12d is configured by a microcomputer including a CPU and a memory. In general, a plurality of electronic devices 10 are provided for one cold water supply device 12.

  A dew condensation sensor 20, which is an example of a dew condensation detector, is provided in the middle of a cold water supply pipe 14 provided between the cold water supply device 12 and the electronic device 10. When the chilled water supply pipeline 14 is short, the dew condensation sensor 20 may be provided at any position of the chilled water supply pipeline 14, but when the chilled water supply pipeline 14 is long, the dew condensation sensor 20 is located near the electronic device 10. It is desirable to arrange in (near). If the environment (temperature, humidity) around the condensation sensor 20 and the environment (temperature, humidity) around the electronic device 10 or around the electronic device 10 are equal, the condensation detection by the condensation sensor 20 is detected in the electronic device 10. It is because it can be considered that it is equal to dew condensation detection.

  The dew condensation sensor 20 detects water droplets due to dew condensation on the object to be measured and outputs a dew condensation detection signal. The dew condensation detection signal output from the dew condensation sensor 20 is supplied to a service processor 10b provided in the control unit 10a of the electronic device 10. The service processor 10b is a CPU that performs control to keep some functions working even when the main power of the electronic device 10 is shut off and the main functions are stopped. For example, when the dew condensation detection signal is supplied, the service processor 10b can shut down the main power supply of the electronic device 10 and stop the operation of the electronic device 10.

  Between the dew condensation sensor 20 and the electronic device 10, a heat transfer unit 30 that is an example of a heat transfer unit that transfers heat from hot water to cold water is provided. The heat transfer unit 30 is provided to supply heat to the cold water that has passed through the dew condensation sensor 20 to increase the temperature of the cold water that enters the electronic device 10. In other words, the heat transfer unit 30 transfers a part of the heat of the hot water flowing out from the electronic device 10 to the hot water circulation pipe 16 to the cold water just before flowing into the electronic device 10 after passing through the dew condensation sensor 20. This is to increase the temperature of the cold water flowing into the electronic device 10 by a predetermined temperature (for example, 2 ° C.).

  In the present embodiment, as shown in FIG. 2, a metal member 40 formed of a metal such as copper, copper alloy, aluminum, aluminum alloy, or the like is used as the heat transfer unit 30 as shown in FIG. 2. The metal member 40 has a shape that fits between the cold water supply line 14 and the hot water reflux line 16. The portions where the metal member 40 contacts the cold water supply pipe 14 and the hot water reflux pipe 16 are joined by a thermal bonding material such as welding, brazing material, or solder.

  In the portion to which the metal member 40 is attached, that is, in the heat transfer unit 30, the temperature of the hot water flowing through the hot water circulation pipe 16 is higher than the temperature of the cold water flowing through the cold water supply pipe 14, so By being transmitted from the path 16 to the metal member 40 and further transmitted to the cold water supply pipe 14, it is transferred to the cold water flowing through the cold water supply pipe 14. By being heated by this heat, the temperature of the cold water flowing into the electronic device 10 rises.

  For example, if the temperature of the cold water passing through the dew condensation sensor 20 (or the temperature of the cold water coming out of the dew condensation sensor 20) is 21 ° C., heat is supplied to the cold water of 21 ° C. and the temperature is raised to 23 ° C., for example. Let 23 ° C. cold water enter the electronic device 10. The cold water that has flowed through the electronic device 10 and cooled the electronic components becomes, for example, 33 ° C. warm water, and is discharged from the electronic device 10 to the hot water recirculation conduit 16.

  For example, it is assumed that the environment in the server room in which the electronic device 10 is installed is maintained at a room temperature of 25 ° C. and a relative humidity of 50% or less, and the temperature of the cold water supplied from the cold water supply device 12 is 21 ° C. . In the environment of the server room, it can be seen that the dew point temperature inside the dew condensation sensor 20 and the electronic device 10 is 13.9 ° C. as determined from the wet air diagram. Therefore, in this environment, also in the dew condensation sensor 20 (21 ° C. same as that of the cold water), the cooling water passage inside the electronic device 10 (23 ° C. same as that of the cold water heated by the heater 30). In this case, the dew point temperature (13.9 ° C.) or lower does not cause condensation.

  Here, for example, it is assumed that the environment in the server room has changed due to a failure of the air conditioner in the server room, and has risen to a room temperature of 28 ° C. and a relative humidity of 70%. At this time, the dew point temperature in the environment in the server room rises to 22 ° C. and becomes higher than the cold water temperature 21 ° C. Therefore, dew condensation occurs in the dew condensation sensor 20 that is 21 ° C., which is the same as cold water. On the other hand, the cooling water passage in the electronic device 10 has a temperature of 23 ° C., which is the same as the temperature of the cold water heated by the heat transfer unit 30, and is higher than the dew point temperature of 22 ° C. Therefore, condensation occurs in the electronic device 10. Absent.

  If the environment in the server room continues to change and the room temperature or relative humidity increases, the dew point temperature further increases from 22 ° C. When the dew point temperature exceeds the cold water temperature of 23 ° C., condensation occurs in the electronic device 10.

  However, after the dew point temperature reaches the temperature 21 ° C. of the dew condensation sensor 20, it takes a certain amount of time to reach the temperature 23 ° C. of the cooling water passage in the electronic device 10. In the meantime, in the dew condensation sensor 20, dew condensation proceeds and water droplets grow, and the dew condensation sensor 20 has a water droplet amount that can detect the water droplets. That is, no condensation has started in the electronic device 10 until the condensation sensor 20 outputs a condensation detection signal after the condensation in the server room has changed and the condensation sensor 20 has started to form a condensation. Is not generated.

  Therefore, by receiving a dew condensation detection signal from the dew condensation sensor 20 and taking a measure such as shutting off the power supply of the electronic device 10, the failure of the electronic device 10 due to dew condensation can be prevented in advance.

  In addition, it is not restricted to using the metal member 40 as the heat transfer part 30, and if the material has good heat transfer, for example, the heat transfer part 30 is formed using a ceramic material, heat conductive plastic, heat conductive rubber, or the like. May be. When a heat conductive plastic is used, a heat transfer adhesive can be used as a bonding material. In addition, when a heat conductive rubber is used, it is preferable to apply a heat conductive grease or liquid to the connecting portion.

  The size and shape of the metal member 40 are determined by the amount of heat to be transferred. The amount of heat to be transferred is, for example, the amount of heat that can raise 21 ° C. cold water to 23 ° C. and the amount of heat that 33 ° C. hot water drops to 31 ° C. in the above description. The amount of heat that can be transferred by the metal member 40 is determined by the thermal conductivity of the metal member 40 and the heat transfer coefficient between the metal member 40, the cold water supply pipe 14, and the hot water reflux pipe 16.

  Further, as another embodiment of the heat transfer section 30, the structure shown in FIG. 3 can be used. The heat transfer unit 30 illustrated in FIG. 3 includes a connection cover 52 wound around the cold water supply pipe 14 and the hot water reflux pipe 16. The connection cover 52 is preferably formed of a heat conductive material. For example, the connection cover 52 is formed of a metal plate such as copper or aluminum.

  A space between the cold water supply pipe 14 and the hot water reflux pipe 16 covered with the connection cover 52 is filled with a heat transfer filler 54 (heat transfer material). The filler 54 is a material having good thermal conductivity such as a thermal sheet or a thermal compound. When a sufficient amount of heat can be transferred only by heat conduction of the filler 54, the connection cover 54 may not be formed of a heat conductive material, and may be formed of, for example, a plastic sheet or a vinyl sheet.

  Moreover, you may strengthen heat conductivity by attaching the metal member 40 shown in FIG. 2, and attaching the connection cover 52 to the circumference | surroundings.

  Here, a dew condensation detection method in the electronic device cooling system will be described with reference to FIG. FIG. 4 is a flowchart of the dew condensation detection process.

  When the dew condensation detection process is started, first, the service processor 10b of the control unit 10a of the electronic device 10 outputs a signal from the dew condensation sensor 20 when the electronic device 10 is activated and the internal heat generating component is cooled. Capture (step S1). Subsequently, the service processor 10b of the electronic device 10 determines whether or not the signal from the dew condensation sensor 20 is a dew condensation detection signal indicating that dew condensation has been detected (step S2). If it is determined in step S2 that the signal from the dew condensation sensor 20 is not a dew condensation detection signal, the process returns to step S1 and takes in the signal from the dew condensation sensor 20 again.

  On the other hand, if it is determined in step S2 that the signal from the dew condensation sensor 20 is a dew condensation detection signal, the process proceeds to step S3. In step S3, the service processor 10b performs a process of shutting down (turning off) the power of the electronic device 10. At this time, the display device may notify the administrator of the dew condensation state, or may issue an alarm to notify the administrator. Alternatively, instead of turning off the power of the electronic device 10, the inside of the electronic device 10 may be dried so as to eliminate condensation.

  While the above dew condensation detection process is being performed, the cold water that has passed through the dew condensation sensor 20 and before entering the electronic device 10 is heated by the heat from the heat transfer unit 30, and is higher than the temperature in the dew condensation sensor 20. Is set to Therefore, the condensation does not start in the electronic device 10 until the condensation is detected after the condensation sensor 20 starts the condensation. As a result, before the condensation starts in the electronic device 10, for example, a countermeasure against the condensation can be taken so that the power of the electronic device 10 is turned off, thereby preventing a failure due to the condensation in the electronic device 10. be able to.

  In FIG. 1, the dew condensation sensor 20 and the heat transfer unit 30 are arranged near the outside of the electronic device 10. However, if a space can be secured inside the electronic device 10, the dew condensation sensor 20 and the heat transfer unit 30 are connected to the electronic device 10. It may be provided inside the device 10.

  Next, a second embodiment will be described. FIG. 5 is a schematic diagram showing an overall configuration of an electronic device cooling system to which the dew condensation detection device according to the second embodiment is attached. 5, parts that are the same as the parts shown in FIG. 1 are given the same reference numerals, and descriptions thereof will be omitted.

  In the electronic device cooling system shown in FIG. 5, a connecting pipe 60 is used as the heat transfer unit 30 for transferring heat to cold water. That is, instead of transferring heat by the metal member 40, a part of the hot water flowing through the hot water circulation pipe 16 is returned to the cold water supply pipe 14 through the connection pipe 60, so that the hot water is mixed with the cold water, and the temperature of the cold water Rises. The connecting pipe 60 transfers the heat of the hot water flowing through the hot water reflux pipe line 16 to the cold water in the cold water supply pipe line 14 and functions as the heat transfer unit 30.

  6 is an enlarged cross-sectional view of a portion A in FIG. The connecting pipe 60 is inserted between the cold water supply pipe 14 and the hot water reflux pipe 16 with one end 60 a inserted into the hot water reflux pipe 16 and the other end 60 b inserted into the cold water supply pipe 14. Provided. One end 60 a of the connection pipe 60 is inserted into the hot water circulation pipe 16 in the vicinity of the electronic device 10, and the other end 60 b is inserted into the cold water supply pipe 14 between the dew condensation sensor 20 and the electronic device 10. An inflow opening 62 is provided on one end 60a side of the connecting pipe 60, and an outflow opening 64 is formed on the other end 60b side.

  The inflow opening 62 opens toward the upstream side of the hot water flow in the hot water circulation pipe 16. The outflow opening 64 opens toward the downstream of the flow of cold water in the cold water supply pipe 14. Therefore, when the warm water discharged from the electronic device 10 flows into the warm water circulation pipe 16, a part of the warm water flows into the inflow opening 62 of the connection pipe 60. Then, the hot water flows through the connection pipe 60 and flows out from the outflow opening 64 to the cold water supply pipe 14. That is, a part of the hot water discharged from the electronic device 10 is mixed with the cold water immediately before the electronic device 10 through the connection pipe 60. Thereby, the temperature of the cold water supplied to the electronic device 10 can be raised by the heat of the mixed hot water.

  For example, if the temperature of the cold water passing through the dew condensation sensor 20 (or the temperature of the cold water coming out of the dew condensation sensor 20) is 21 ° C., the hot water is mixed with the cold water of 21 ° C. and the temperature is raised to 23 ° C., for example. Let 23 ° C. cold water enter the electronic device 10. It is assumed that the cold water that has flowed through the electronic device 10 and cooled the electronic components becomes, for example, 33 ° C. warm water and is discharged from the electronic device 10 to the hot water circulation conduit 16.

  For example, it is assumed that the environment in the server room in which the electronic device 10 is installed is maintained at a room temperature of 25 ° C. and a relative humidity of 50% or less, and the temperature of the cold water supplied from the cold water supply device 12 is 21 ° C. . The flow rate of cold water supplied from the cold water supply device 12 is assumed to be 450 ml / min. Hot water is supplied to the cold water after passing through the dew condensation sensor 20 via the connecting pipe 60. Assuming that the flow rate of hot water (33 ° C.) flowing through the connecting pipe 60 is 150 ml / min, cold water in which 150 ml / min hot water (33 ° C.) is mixed with 450 ml / min cold water (21 ° C.) is supplied to the electronic device 10. Supplied. The temperature of the cold water supplied to the electronic device 10 rises due to the merging of hot water and reaches 23 ° C. Therefore, 600 ml / min of cold water (23 ° C.) is supplied to the electronic device 10.

  Assuming that the heat generation amount of the electronic components in the electronic device 10 is 420 W, the cold water having a temperature of 23 ° C. and a flow rate of 600 ml / min absorbs this heat generation amount to become hot water having a temperature of 33 ° C. It is discharged to the path 16. A portion of the 33 ° C. hot water (150 ml / min as described above) flows into the connecting pipe 60 as soon as it is discharged from the electronic device 10, and the remaining 450 ml / min hot water (33 ° C.) is supplied to the cold water supply device 12. Return to. The cold water supply device 12 cools 450 ml / min of hot water (33 ° C.) to generate 450 ml / min of cold water (21 ° C.), and supplies the cold water to the cold water supply line 14.

  In the environment in the server room described above, the dew point temperature inside the dew condensation sensor 20 and the electronic device 10 is found to be 13.9 ° C. when determined from the wet air diagram. Therefore, in this environment, also in the dew condensation sensor 20 (21 ° C. same as that of the cold water), the cooling water passage inside the electronic device 10 (23 ° C. same as that of the cold water heated by the heater 30). In this case, the dew point temperature (13.9 ° C.) or lower does not cause condensation.

  Here, for example, it is assumed that the environment in the server room has changed due to a failure of the air conditioner in the server room, and has risen to a room temperature of 28 ° C. and a relative humidity of 70%. At this time, the dew point temperature in the environment in the server room rises to 22 ° C. and becomes higher than the cold water temperature 21 ° C. Therefore, dew condensation occurs in the dew condensation sensor 20 that is 21 ° C., which is the same as cold water. On the other hand, the cooling water passage in the electronic device 10 has a temperature of 23 ° C., which is the same as the temperature of the cold water heated by the heat transfer unit 30, and is higher than the dew point temperature of 22 ° C. Therefore, condensation occurs in the electronic device 10. Absent.

  If the environment in the server room continues to change and the room temperature or relative humidity increases, the dew point temperature further increases from 22 ° C. When the dew point temperature exceeds the cold water temperature of 23 ° C., condensation occurs in the electronic device 10.

  However, after the dew point temperature reaches the temperature 21 ° C. of the dew condensation sensor 20, it takes a certain amount of time to reach the temperature 23 ° C. of the cooling water passage in the electronic device 10. In the meantime, in the dew condensation sensor 20, dew condensation proceeds and water droplets grow, and the dew condensation sensor 20 has a water droplet amount that can detect the water droplets. That is, no condensation has started in the electronic device 10 until the condensation sensor 20 outputs a condensation detection signal after the condensation in the server room has changed and the condensation sensor 20 has started to form a condensation. Is not generated.

  As described above, also in the present embodiment, the temperature of the cold water after passing through the dew condensation sensor 20 can be increased similarly to the first embodiment described above, and the same effect as in the first embodiment can be obtained. . Therefore, by receiving a dew condensation detection signal from the dew condensation sensor 20 and taking a measure such as shutting off the power supply of the electronic device 10, the failure of the electronic device 10 due to dew condensation can be prevented in advance.

  In addition, although the connection piping 60 of the shape shown in FIG. 7 is used as the heat transfer part 30, the shape of the connection piping is not limited to this shape. The shape / configuration capable of taking in a part (predetermined flow rate) of the hot water flowing through the hot water circulation pipe 16 and supplying it to the cold water supply pipe 14 is various shapes / configurations in addition to the shape / configuration shown in FIG. Can think. As an example, as shown in FIG. 8, inclined plates 72 and 74 can be provided at both ends 70 a and 70 b of a cylindrical pipe 70 having both ends opened to control the flow of hot water. Alternatively, although not illustrated, both ends of the cylindrical pipe are cut obliquely, and the obliquely cut surface faces the upstream direction of the hot water flow on the hot water reflux pipe line 16 side, and conversely, on the cold water supply pipe side. The pipe may be attached so that the surface cut in the direction of the cold water faces the downstream direction of the flow of cold water.

  Here, in the first and second embodiments described above, when the heat generation amount of the electronic component that is the heat generating component in the electronic device 10 is constant, the temperature of the dew condensation sensor 20 and the temperature of the electronic component in the electronic device 10 are the same. The difference (temperature difference) is constant. Therefore, the time from when the dew condensation is detected by the dew condensation sensor 20 until the dew condensation occurs inside the electronic device 10 is also constant. The electronic device 10 such as a server may have a different heat generation amount depending on the electronic device 10, and even in the same electronic device 10, the heat generation amount varies due to a load variation on the electronic component.

  Therefore, an optimum temperature difference can be set by adjusting the amount of heat transferred by the heat transfer unit 30, and the system power supply is turned on before the condensation sensor 20 detects the condensation and before the condensation occurs in the electronic device 10. Shut off and stop safely. For an electronic device with a small load fluctuation, if an optimum design is performed in advance, it is possible to take measures against condensation only by providing the heat transfer unit 30 as in the first and second embodiments.

  On the other hand, in an electronic device having a high load fluctuation, such as a server, if the amount of heat transferred by the heat transfer unit 30 is set in accordance with the state where the load on the electronic component is the lowest (the state where the heat generation amount is small), the load is high. If this happens, the cooling of the electronic components will be insufficient. For this reason, the operating temperature of the electronic component becomes high, which causes a reduction in the life of the electronic component and an increase in the failure rate. Conversely, when the amount of heat transferred by the heat transfer unit 30 is set in accordance with the highest load state, when the load is low, the temperature of the dew condensation sensor 20 and the internal temperature of the electronic device 10 (the temperature of the electronic component) The temperature difference becomes smaller. In such a situation, the time from when the dew condensation sensor 20 detects dew condensation to when dew condensation occurs in the electronic device 10 is short, and there is a possibility that the system power supply cannot be shut off reliably and stopped safely. .

  In order to solve such a problem, the flow rate of the cold water supplied from the cold water supply device 12 is controlled / adjusted based on the temperature of the hot water flowing back through the hot water circulation pipe 16. That is, the temperature of the hot water returned to the cold water supply device 12 is measured, and the flow rate of the cold water generated by the cold water supply device 12 is controlled based on the measured temperature. In this case, the supply amount of the cold water is set to a flow rate that matches the lowest load state in the initial setting. If the temperature of the hot water exceeds a certain threshold, the cooling capacity of the electronic component by the cold water can be increased by increasing the flow rate of the supplied cold water, and the operating temperature of the electronic component can be kept low. Thereby, the temperature difference between the temperature of the dew condensation sensor 20 and the temperature of the electronic component can also be maintained within a certain range.

  FIG. 9 is a flowchart of a cold water flow rate control process for adjusting the amount of cold water supplied. The cold water flow rate control process is repeated at regular intervals.

  When the cold water flow rate control process is started, first, the control unit 12d of the cold water supply device 12 acquires the temperature Tw of the hot water that has flowed back through the hot water circulation pipe 16 (S11). The temperature Tw of the hot water can be detected by the water temperature sensor 12a.

  Next, the control unit 12d of the cold water supply device 12 compares the temperature Tw of the obtained hot water with the temperature threshold (step S12). The temperature threshold includes an upper limit threshold UTH and a lower limit threshold LTH. When the temperature of the hot water is not more than the upper limit threshold value UTH and not less than the lower limit threshold value UTH, the temperature of the returning warm water is an appropriate temperature, and the electronic components in the electronic device 10 are appropriately cooled. And the process ends. Although the chilled water flow rate control process is repeatedly performed at regular time intervals, the process may return to step S11 so that the next process is started immediately after the process is completed.

  If the temperature Tw of the hot water is higher than the upper limit threshold value UTH, it is determined that the electronic components in the electronic device 10 are not sufficiently cooled, and the process proceeds to step S13. In step S13, the flow rate of the cold water (21 ° C.) supplied from the cold water supply device 12 to the cold water supply pipe 14 (that is, the electronic device 10) is increased by a predetermined amount, and then the process ends. Although the chilled water flow rate control process is repeatedly performed at regular time intervals, the process may return to step S11 after step S13 so that the next process is started immediately after the process is completed.

  On the other hand, if the temperature Tw of the hot water is lower than the lower limit threshold LTH, it is determined that the electronic components in the electronic device 10 are sufficiently cooled, and the process proceeds to step S14. In step S14, the flow rate of the cold water (21 ° C.) supplied from the cold water supply device 12 to the cold water supply pipe 14 (that is, the electronic device 10) is decreased by a predetermined amount, and then the process ends. Although the chilled water flow rate control process is repeatedly performed at regular time intervals, the process may return to step S11 after step S14 so that the next process is started immediately after the process is completed.

  Next, a third embodiment will be described. FIG. 10 is a schematic diagram showing an overall configuration of an electronic device cooling system to which the dew condensation detection device according to the third embodiment is attached. 10, parts that are the same as the parts shown in FIG. 5 are given the same reference numerals, and descriptions thereof will be omitted.

  In the electronic device cooling system shown in FIG. 10, a connection pipe 60 is used as the heat transfer unit 30 for transferring heat to cold water, as in the second embodiment described above. However, as the thermal phase portion 30, a metal member 40 may be used as in the first embodiment.

  In the present embodiment, a heater 80 that is an example of a heating unit is provided between the dew condensation sensor 20 and the electronic device 10. The heater 80 is provided to heat the cold water that has passed through the dew condensation sensor 20 and raise the temperature of the cold water that enters the electronic device 10. In the first and second embodiments described above, the chilled water that has passed through the dew condensation sensor 20 is heated by the heat transferred by the heat transfer unit 30 and becomes chilled water that is higher by a predetermined temperature in the electronic device 10. Supplied.

  However, for example, when the electronic device 10 is in a standby state and the load on the electronic component is extremely small, the temperature of the hot water discharged from the electronic device 10 may be extremely low. In such a case, a sufficient temperature difference between the temperature of the dew condensation sensor 20 and the internal temperature of the electronic device 10 cannot be obtained, and dew condensation occurs inside the electronic device 10 after dew condensation is detected by the dew condensation sensor 20. It will not be possible to take enough time.

  Therefore, in the present embodiment, when the temperature of the hot water becomes extremely low, the heater 80 is driven and the temperature of the cold water supplied to the electronic device 10 is increased by heating with the heat of the heater 80, thereby increasing the temperature of the electronic device. 10 Condensation inside is suppressed.

  In FIG. 10, the dew condensation sensor 20, the heat transfer unit 30 (connection pipe 60), and the heater 80 are arranged in the vicinity outside the electronic device 10. However, if a space can be secured inside the electronic device 10, dew condensation is achieved. The sensor 20, the heat transfer unit 30 (connection pipe 60), and the heater 80 may be provided inside the electronic device 10.

  In FIG. 10, the heater 80 is provided between the connection pipe 60 and the electronic device 10. However, the heater 80 may be attached between the condensation sensor 20 and the connection pipe 60, or the heater 80 may be attached to the condensation sensor 20. It is good also as attaching to. In this case, it is preferable to provide a thermal insulator between the heater 80 and the dew condensation sensor 20 so that the heat of the heater 80 is not transmitted to the dew condensation sensor 20. As described above, the heater 80 may be disposed at any position as long as it can raise the temperature of the cold water after leaving the dew condensation sensor 20 and before entering the electronic device 10. The dew condensation sensor 20, the heat transfer unit 30 (connection pipe 60), and the heater 80 constitute a dew condensation detection device.

  As the heater 80, a heater that performs heating by electric energy such as an electric heater (resistance heater) or an induction heater can be used. Alternatively, instead of the heater 80, heating may be performed using heat from a heating element of a peripheral device of the electronic device 10.

  FIG. 11 is a flowchart of a cold water flow rate control process performed by the electronic device cooling system shown in FIG. The cold water flow rate control process is repeated at regular intervals. In FIG. 11, steps that are the same as the steps shown in FIG. 9 are given the same step numbers, and descriptions thereof are omitted.

  In the chilled water flow rate control process shown in FIG. 11, if it is determined in step S12 that the temperature Tw of the hot water is lower than the lower limit threshold LTH, it is determined that the electronic components in the electronic device 10 are sufficiently cooled, and the process proceeds to step S21. move on. In step S21, the control unit 12d of the chilled water supply device 12 determines whether the flow rate of chilled water (21 ° C.) supplied from the chilled water supply device 12 to the chilled water supply pipeline 14 (that is, the electronic device 10) is equal to or higher than the flow rate lower limit value. Determine.

  When the flow rate of the cold water to be supplied is equal to or higher than the lower limit value of the flow rate (YES in step S21), the process proceeds to step S22. In step S22, the flow rate of the cold water (21 ° C.) supplied from the cold water supply device 12 to the cold water supply pipe 14 (that is, the electronic device 10) is decreased by a predetermined amount, and then the process ends. Although the chilled water flow rate control process is repeatedly performed at regular time intervals, the process may return to step S11 after step S22 so that the next process is started immediately after the process is completed.

  On the other hand, when the flow rate of the cold water to be supplied is less than the lower limit value of the flow rate (NO in step S21), the process proceeds to step S23. In step S23, the flow rate of the cold water (21 ° C.) supplied from the cold water supply device 12 to the cold water supply pipe 14 (that is, the electronic device 10) is maintained as it is, and the heater 80 is driven. Thereby, the temperature of the cold water supplied to the electronic device 10 rises due to the heating of the heater 80, and a sufficient difference between the temperature of the dew condensation sensor 20 and the internal temperature of the electronic device 10 can be taken. After driving the heater 80 in step S23, the process ends. Although the chilled water flow rate control process is repeatedly performed at regular time intervals, the process may return to step S11 after step S23 so that the next process is started immediately after the process of step 23 is completed.

  FIG. 12 is a time chart showing the operation and temperature change of each part when the cold water flow rate control process shown in FIG. 11 is performed.

  Until time A, it is assumed that a certain amount of heat is generated by the operation of the electronic components in the electronic device 10 and is sufficiently cooled by a certain amount of cold water from the cold water supply device 12. Therefore, until the time A, the temperature of the hot water discharged from the electronic device 10 (that is, the temperature of the hot water returning to the cold water supply device) is constant. Therefore, the difference between the temperature of the dew condensation sensor 20 and the internal temperature of the electronic device 10 is kept constant with a sufficient temperature difference.

  At time A, for example, it is assumed that the operating state of the electronic device 10 has changed and the load on the electronic component has decreased, and the amount of heat generated by the electronic component has decreased, as shown in FIG. At this time, as shown in FIG. 12- (d), the temperature of the hot water discharged from the electronic device 10 decreases with a slight time difference. When the control unit 12d of the chilled water supply device 12 detects the temperature drop of the hot water from the detected value of the water temperature sensor 12a, the chilled water supply amount (the flow rate of chilled water) is reduced by a predetermined flow rate as shown in FIG. . As a result, as shown in FIG. 12- (d), the temperature of the warm water slightly increases and then rises and returns to the original constant temperature. At this time, the difference (temperature difference) between the temperature of the dew condensation sensor 20 and the internal temperature of the electronic device 10 is also slightly reduced to return to the original temperature difference as shown in FIG. The above state change is a state change by the processing of steps S11, S12, S21, and S22 in the flowchart shown in FIG.

  Next, it is assumed that at time B, the operating state of the electronic device 10 changes and the load on the electronic component increases, and the amount of heat generated by the electronic component increases as shown in FIG. At this time, as shown in FIG. 12- (d), the temperature of the hot water discharged from the electronic device 10 rises with a slight time difference. When the control unit 12d of the chilled water supply device 12 detects the temperature rise of the hot water from the detection value of the water temperature sensor 12a, the chilled water supply amount (the flow rate of chilled water) is increased by a predetermined flow rate as shown in FIG. . As a result, as shown in FIG. 12- (d), the temperature of the hot water slightly increases and then decreases, and returns to the original constant temperature. At this time, the difference between the temperature of the dew condensation sensor 20 and the internal temperature of the electronic device 10 (temperature difference) also increases slightly as shown in FIG. The above state change is a state change by the processing of steps S11, S12, and S13 in the flowchart shown in FIG.

  Next, at time C, for example, the operating state of the electronic device 10 is changed, the load of the electronic component is greatly reduced, and the amount of heat generated by the electronic component is greatly reduced as shown in FIG. . At this time, as shown in FIG. 12- (d), the temperature of the hot water discharged from the electronic device 10 decreases with a slight time difference. When the controller 12d of the cold water supply device 12 detects a decrease in the temperature of the hot water from the detection value of the water temperature sensor 12a, the control unit 12d reduces the supply amount of cold water (the flow rate of cold water) by a predetermined flow rate.

  However, since the amount of heat generated by the electronic components is greatly reduced, the temperature of hot water continues to rise even if the amount of cold water supplied is reduced, and the amount of cold water supplied is further reduced accordingly. Then, the supply amount of cold water (flow rate of cold water) is greatly reduced, and as shown in FIG. Then, in order to increase the temperature of the cold water in order to maintain the temperature difference, the power supply of the heater 80 is turned on and a voltage is applied to the heater 80 as shown in FIG. Thereby, the heater 80 generates heat and the cold water supplied to the electronic device 10 is heated.

  When the cold water supplied to the electronic device 10 is heated by the heater 80, as shown in FIG. 12- (d), the temperature of the hot water discharged from the electronic device 10 rises again and returns to the original constant temperature. . Accordingly, the temperature difference increases again as shown in FIG. 12- (e) and returns to the original temperature difference. For this reason, it is possible to secure a time from when the dew condensation sensor 20 detects the dew condensation until the dew condensation occurs inside the electronic device 10, and it is possible to take dew condensation measures such as turning off the system power in advance.

  The change in state after time C is a change in state due to the processing in steps S11, S12, S21, S22, S112, S12, S21, and S23 in the flowchart shown in FIG.

  As mentioned above, although the present invention has been described with the embodiment relating to the dew condensation detection device, the present invention is not limited to the specifically disclosed embodiment, and various modifications and improvements can be made without departing from the scope of the present invention. It will be.

DESCRIPTION OF SYMBOLS 10 Electronic device 10a Control part 10b Service processor 12 Chilled water supply apparatus 12a, 12b Water temperature sensor 12c Flow controller 12d Control part 14 Chilled water supply line 18 Hot water reflux line 20 Condensation sensor 30 Heat transfer part 40 Metal member 52 Connection cover 54 Filler 60 Connecting piping 62 Inflow opening 64 Outflow opening 70 Piping 72, 74 Inclined plate 80 Heater

Claims (16)

A dew condensation detector that is provided in a supply line for supplying a cooling medium from the cooling medium supply device to the apparatus to be cooled and detects water droplets due to dew condensation;
Heat is transferred from the cooling medium flowing through the reflux line returning the cooling medium from the cooled apparatus to the cooling medium supply apparatus to the cooling medium flowing through the supply line between the dew condensation detector and the cooled apparatus. A dew condensation detection device having a heat transfer section. The dew condensation detection device according to claim 1,
The said heat transfer part is a dew condensation detection apparatus which is a heat-transfer member which contacts the said supply pipe line and the said reflux flow line. The dew condensation detection device according to claim 2,
The said heat-transfer member is a dew condensation detection apparatus which is a metal material joined to the said supply pipe line and the said recirculation pipe line. The dew condensation detection device according to claim 1,
The heat transfer unit is filled in a connection cover that surrounds the supply pipe line and the reflux pipe line in a loop shape, and a space between the supply pipe line and the reflux pipe line surrounded by the connection cover. Condensation detection device including a heat transfer material. The dew condensation detection device according to claim 4,
The dew condensation detection device, wherein the heat transfer material is a thermal sheet or a thermal compound. The dew condensation detection device according to claim 1,
The said heat transfer part is a dew condensation detection apparatus which is a connection piping which supplies a part of cooling medium which flows through the said circulation pipe to the said supply pipe. The dew condensation detection device according to claim 6,
One end of the connection pipe is inserted into the reflux pipe, and the other end is inserted into the supply pipe.
A dew condensation detection device provided with an inflow opening through which the cooling medium flows in on one end side and an outflow opening through which the cooling medium flows out on the other end side. The dew condensation detection device according to claim 6,
One end of the connection pipe is inserted and opened in the reflux line, and the other end is inserted and opened in the supply line.
A dew condensation detection device in which an inclined plate for controlling a flow of a cooling medium is provided on each of the one end and the other end. The dew condensation detection device according to claim 1,
The dew condensation detection apparatus which further has a heating part provided in the said supply pipe line between the said dew condensation detector and the said to-be-cooled apparatus. The dew condensation detection device according to claim 9,
The dew condensation detection device, wherein the heating unit is an electric heater. A cooled device that cools internal components with a cooling medium;
A cooling medium supply device for generating a cooling medium to be supplied to the cooled device;
A supply line for connecting the cooled device and the cooling medium supply device, and supplying a cooling medium from the cooling medium supply device to the cooled device;
A recirculation conduit for connecting the cooled device and the cooling medium supply device and returning the cooling medium from the cooled device to the cooling medium supply device;
A dew condensation detector provided in the middle of the supply line;
A cooling system comprising: a heat transfer unit configured to move heat of the cooling medium flowing through the reflux pipe to the cooling medium flowing through the supply pipe between the dew condensation detector and the device to be cooled. A cooling system according to claim 11, comprising:
The said heat transfer part is a cooling system which is a heat-transfer member which contacts the said supply pipe line and the said reflux flow line. A cooling system according to claim 11, comprising:
The cooling system, wherein the heat transfer unit is a connecting pipe that supplies a part of a cooling medium flowing through the reflux pipe to the supply pipe. A cooling medium flow rate control method for controlling a flow rate of a cooling medium supplied to an apparatus to be cooled,
Detecting the temperature of the cooling medium discharged from the device to be cooled;
A cooling medium flow rate control method for comparing a detected temperature with a temperature threshold and controlling a flow rate of a cooling medium supplied to the apparatus to be cooled based on a comparison result. The cooling medium flow rate control method according to claim 14,
The temperature threshold includes an upper threshold and a lower threshold,
When the detected temperature is higher than the upper limit threshold, increase the flow rate of the cooling medium supplied to the cooled device,
When the detected temperature is lower than the lower limit threshold, the flow rate of the cooling medium supplied to the cooled device is reduced,
Cooling medium flow rate control method. The cooling medium flow rate control method according to claim 15,
When the detected temperature is lower than the lower limit threshold, the flow rate of the cooling medium supplied to the cooled device is compared with the lower limit flow rate,
When the flow rate of the cooling medium supplied to the cooled device is equal to or higher than the flow rate lower limit value, the flow rate of the cooling medium supplied to the cooled device is reduced,
When the flow rate of the cooling medium supplied to the cooled apparatus is less than the lower limit value of the flow rate, the cooling medium supplied to the cooled apparatus is heated between the dew condensation detection position and the cooled apparatus.
Cooling medium flow rate control method.

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