JPH0510580B2 - - Google Patents

Description

[Detailed description of the invention] [Technical field to which the invention pertains]

This invention is a water cooling system that uses cold air heat blown out from an air conditioner in a room in which the device is installed to remove the heat generated by the operation of the electronic device, for example, when an electronic device such as a computer equipment is subject to a heat load. The present invention relates to a type cooling device.

[Prior art and its problems]

First, an outline of the equipment of a water-cooled cooling device, which is an object of the present invention and whose heat load is the electronic device described above with reference to FIG. 5, will be explained. In the figure, 1 is an electronic device, 2 is a water-cooled cooling device for cooling the electronic device,
3 is a machine room in which these devices are housed and installed, and 4 is an indoor air conditioner. Here, the machine room 3 has a floor surface as an access floor 31, and cold air outlets 33 and 34 are distributed over a part of the floor surface and communicate with a cold air supply duct 32 formed under the floor. Further, an air outlet 35 is opened on the ceiling side of the room, and the air conditioner 4 described above is connected to an air circulation path 36 that connects this air outlet 35 and the inlet of the cold air supply duct 32. By operating the air conditioner 4, air-conditioned cold air is blown into the room as indicated by arrow A.
On the other hand, the water-cooled cooling device 2 includes an air/water heat exchanger 21 installed on the indoor floor facing the cold air outlet 33 opened on the floor, and an air/water heat exchanger 21 and an electronic Device 1, especially a water-cooled object 1 as a heat sink installed in a power device that generates a large amount of heat.
Cooling water circulation path 2 piped across 1
2. It is composed of a cooling water tank 23, a water circulation pump 24, etc., which are interposed in the cooling water circulation path 22. The air/water heat exchanger 21 includes a wind cylinder 25 with open upper and lower surfaces, a heat exchanger main body 26 disposed inside the wind cylinder 25, and a plurality of fans arranged in parallel above the heat exchanger main body 26. It is constructed as an assembly such as 27. In such equipment, when the electronic device 1 is operated, the indoor air conditioner 4 is operated to blow out the air-conditioned cold air flow A indoors, and in the water-cooled cooling device 2, the water circulation pump 24 is operated to supply cooling water to the cooling water circulation path 22. is circulated, and the fan 27 is operated. Therefore, the air-conditioning cold air flow A blown out from the cold air outlet 33 opened on the floor surface of the room flows into the air/water heat exchanger 21.
The air is drawn into the wind barrel 25, and the heat retained in the cooling water is radiated to the air side through heat exchange with the cooling water.
As a result, the heat generated in the electronic device 1 is removed by the air/water heat exchanger 2 using the cooling water as a heat transfer medium. The air-conditioned cold air blown into the room from another cold air outlet 34 cools the electronic device 1 and its peripheral devices. In this case, the rated operating temperature of electronic equipment, such as computer equipment, is specified within the range of, for example, 15 to 30°C, and for this purpose, the air / Fan 27 installed in water heat exchanger 21
The number of units in operation, the rotation speed, etc. are controlled, and the heat dissipation capacity of the air/water heat exchanger 21 is controlled to maintain a predetermined operating temperature. However, as described above, the water-cooled cooling device for an electronic device that uses cold air blown from an indoor air conditioner to radiate heat has the following problems. In other words, in a machine room where electronic equipment, etc. are installed, the indoor air conditioner 4 is always operated to prevent adverse effects on the equipment due to changes in indoor temperature, such as condensation on the equipment, regardless of whether the electronic equipment is running or stopped. We try to maintain an appropriate temperature indoors. Further, in this case, the temperature of the air-conditioned cold air blown into the room from the cold air supply duct under the floor is usually considerably lower than the set temperature in the room.
Therefore, even when the electronic device 1 is out of operation, that is, the water-cooled cooling device 2 is also out of operation, the indoor air conditioner 4 continues to operate, so the air/water heat exchange is performed by the cold air blown out through the cold air outlet 33. The heat dissipation function of the device 21 is activated, and in this state there is no heat load on the electronic device side, so the cooling water is in a lower temperature state that is subcooled compared to during normal operation. As an actual measurement example regarding this point, during seasons such as winter when the ambient temperature is low, the temperature of the cooling water in the system of the water-cooled cooling device 2 may drop to a temperature close to 0°C. The state in which such a phenomenon occurs is explained using the operational balance diagram of the air blowing system shown in Fig. 6.During normal operation, the fan 27 of the air/water heat exchanger 21 is operated, so there is no energy in the heat exchanger. The amount of air flowing is Q1 given by the intersection of the combined air blowing characteristics and the air blowing characteristics of the heat exchanger. On the other hand, even if the fan 27 of the air/water heat exchanger 21 is stopped when the electronic device is out of operation,
The air/water heat exchanger 21 has an air volume Q2 given by the intersection of the air blowing characteristics of the air conditioning system and the air blowing characteristics of the heat exchanger.
The air-conditioned cold air flows through the heat exchanger, which acts as a heat dissipator. On the other hand, in order to quickly establish steady operation of the electronic device 1 when the electronic device 1 is restarted under the above-mentioned situation, the low-temperature cooling water that was in a supercooled state during the suspension of operation should be drained for as short a time as possible. During this time, it is necessary to raise the temperature to about 15°C, which is the operating temperature of electronic equipment. That is, in the rise characteristic diagram of the cooling water temperature shown in FIG. 7, the cooling water temperature in the stopped state is To, the target temperature of the cooling water required when restarting the operation of the electronic device is T1, and the electronic temperature is set at time ho. It is desirable that the time required for the cooling water temperature to reach the temperature T1 at time h1 when restarting the operation of the device and the air/water heat exchanger is as short as possible. However, as mentioned above, if the cooling water temperature decreases due to heat exchange with the air conditioner cold air that continues during the period of suspension of operation, the amount of air flow of the air conditioner cold air will increase even more due to fan operation after operation resumes. Therefore, the time h2 (h2=h1-ho) required to raise the cooling water temperature to T1 becomes longer, and the establishment of steady operation of the electronic device is delayed accordingly. In addition, under operating conditions where the heat load on the electronic equipment side is small and the amount of heat released by the air/water heat exchanger is greater than the amount of heat generated, the cooling water temperature should be raised to the predetermined temperature increase temperature T1. There may also be a situation where steady operation of the electronic device cannot be established due to the failure of the electronic device. To this end, attempts have been made in the past to forcibly raise the temperature of the cooling water by equipping the cooling water tank 23 interposed in the cooling water circulation path 22 in FIG. 5 with an electric heater or the like. This method increases power consumption and is uneconomical.

[Purpose of the invention]

This invention was made in consideration of the above points, and it slightly controls the operation of the fan installed in the air/water heat exchanger without using a secondary heating means such as a heater as in the conventional method. It is an object of the present invention to provide a water-cooled cooling device that can quickly raise the temperature of circulating cooling water supplied to an object to be cooled according to operating conditions on the heat load side, such as when restarting operation of an electronic device. shall be.

[Key points of the invention]

In order to achieve the above object, this invention
The fan of the water heat exchanger is a reversible fan, and during normal cooling operation, the fan is operated in the normal direction to actively suck and guide the air conditioned cold air to the air/water heat exchanger, and to reduce the heat load. When the cooling water temperature is raised earlier than the air-conditioned cold air temperature depending on the operating conditions, the fan is operated in reverse, and the air-conditioned cold air is suppressed from being guided to the air/water heat exchanger, thereby reducing its heat dissipation capacity. This makes it possible to quickly raise the temperature of the cooling water and expand the temperature control range.

[Embodiments of the invention]

FIGS. 1 and 2 each show an operation control circuit diagram of an air/water heat exchanger according to a different embodiment of the present invention, and parts corresponding to those in FIG. 5 are given the same reference numerals. That is, according to the present invention, the fan 27 installed in the wind barrel 25 of the air/water heat exchanger 21 is configured as a reversible fan, and the first
In the embodiment shown in the figure, an operation control means is provided between the fan 27 and the power supply to switch the direction of rotation of the fan 27 between forward and reverse rotation according to a command, and in the embodiment shown in FIG. In addition, it is equipped with operation control means that simultaneously controls the rotational speed of the fan during reverse operation. That is, the reversible fan 27 is equipped with a three-phase motor, and in FIG. In the embodiment shown in FIG. 2, the operation control means is an electromagnetic switch 5 for switching the phase, and a fan rotation speed as an inverter or a voltage regulator connected to the contact circuit on the reverse side. It is equipped with a control device 6. The rotation speed control device 6 is arranged near the radiator 26 inside the air/water heat exchanger 21, and controls the fan as described below based on the output signal of a sensor 7 that detects the wind speed or wind pressure inside the body at that position. 27 to increase/decrease the rotation speed. In this configuration, during normal cooling operation when the electronic device 1 shown in FIG. It is operated to actively suck and guide cold air A into the air/water heat exchanger 21. As a result, as described in FIG. 5, the heat retained in the cooling water is radiated to the air side through heat exchange with the low-temperature air conditioning cold air, and the heat generated on the electronic device side is removed. On the other hand, as mentioned earlier, when restarting electronic equipment after a suspension of operation, cooling water that has been exposed to the air conditioning cold air flow A during the previous suspension period and has reached a supercooled low temperature state is used to operate the electronic equipment. When raising the temperature to a predetermined target temperature, a command is given to the electromagnetic switch 5 of the control means to switch the contact point from 51 to 52, and the fan 27 is operated in reverse. As a result, in the air/water heat exchanger 21, indoor air is pushed into the wind barrel 25 from above against the flow of air-conditioned cold air blown out from below through the cold air outlet 33 on the floor side. As a result, air conditioning cold air flow A
The air flow B and the air flow B introduced from above cancel each other out, so that almost no ventilation flows around the heat exchanger main body 26. Therefore, the heat dissipation capacity of the air/water heat exchanger 21 decreases, and as shown in the coolant rise characteristic diagram shown in Fig. 3, the time h3 required to raise the coolant temperature from To to T1 is reduced. The required time h2 according to the conventional method shown in FIG. 7 can be significantly shortened. Note that when the cooling water temperature rises to a predetermined target temperature T1, this temperature rise is detected and the electromagnetic switch 5 of the control means is switched, the fan 27 is switched from reverse rotation to normal rotation operation, and from then on, normal cooling is performed. I go back to driving. Furthermore, if the ventilation condition in the air/water heat exchanger during the above-mentioned reverse operation is expressed on the operational balance diagram of the ventilation system shown in Figure 4, when the fan 27 is stopped, As shown, the air volume Q2 of air-conditioned cold air is flowing through the air/water heat exchanger 21, but due to the reversal of the fan 27, the air blowing characteristics are as shown in characteristic line A, and therefore the combined air blowing characteristics are as shown in characteristic line E. Therefore, the air volume is reduced to Q3 given by the intersection of this and the heat exchanger air blowing characteristic on the reverse side (-), and this reduces the heat dissipation capacity of the air/water heat exchanger to the normal operating state. This will be significantly reduced compared to . Furthermore, as in the embodiment shown in FIG. 2, a fan rotation speed control device 6 is installed to control the fan 2 during reverse operation.
By variously adjusting the rotation speed of 7, the air blowing characteristics when the fan is reversed in Fig. 4 change as shown by characteristic lines A to D, and along with this, the overall air blowing characteristics that are combined with the air conditioning system's air blowing characteristics also change. The characteristic line begins to change like Ho-chi. Here, the ventilation state inside the wind barrel of the air/water heat exchanger 21 is detected by the sensor 7 disposed near the heat exchanger main body 26, and the wind speed or wind pressure at this detection position is set to 0. In the figure, if the rotation speed of the fan 27 is controlled so that the air blowing characteristic during the reverse rotation becomes the characteristic line C, the overall air blowing characteristic becomes as shown in the characteristic line G, and the amount of forced air guided by the air conditioner cold air flow A and the fan 27 in the reverse direction. B exactly cancel each other out, and the air volume Q4 flowing near the heat exchanger main body 26 inside the air/water heat exchanger 21 becomes zero. This minimizes the heat dissipation capacity of the exchanger,
The time h3 required for the rise in temperature of the cooling water described in FIG. 3 can be shortened to the minimum time. Further, by appropriately combining the normal rotation operation and the reverse rotation operation described above, it is possible to expand the temperature control range of the cooling water.

【Effect of the invention】

As described above, according to the present invention, the fan of the air/water heat exchanger is a reversible fan, and during normal cooling operation, the fan is operated in normal rotation to transfer air-conditioned cold air to the air/water heat exchanger. At the same time, if the cooling water temperature is to be raised earlier than the air conditioner cold air temperature due to heat load operating conditions, the fan is operated in reverse to draw air conditioner cold air to the air/water heat exchanger. By suppressing the air flow and reducing its heat dissipation capacity, the heat load will be supercooled by air conditioner cold air and remain at a low temperature depending on the operating conditions of the heat load, such as when restarting the operation of electronic equipment as a heat load. When raising the temperature of the circulating cooling water to the target temperature, it is cooled by a simple means of controlling the operation of the fan installed in the air/water heat exchanger, without using secondary temperature raising means such as a heater as in conventional methods. Water can be quickly heated to the target temperature, and the temperature control range can be expanded.

[Brief explanation of the drawing]

1 and 2 are operation control circuit diagrams of a fan installed in an air/water heat exchanger showing different embodiments of the present invention, and FIG. 3 is an operation control circuit diagram of a fan according to the present invention and its cooling water. Temperature rise characteristic diagram, Figure 4 is an operational balance diagram of the air blowing system when the fan is operated in reverse relative to the air/water heat exchanger, and Figure 5 is a schematic configuration diagram of the entire water-cooled cooling system that handles the heat load of electronic equipment. , Figure 6 is an operational balance diagram of the air blowing system due to operation and stoppage of the air/water heat exchanger fan in Figure 5, and Figure 7 is a temperature rise characteristic diagram of the cooling water corresponding to Figure 6. be. In each figure, 1: electronic device as heat load, 11: water-cooled object to be cooled, 2: water-cooled cooling device, 21: air/water heat exchanger, 22: cooling water circulation path, 24: water circulation pump, 25: Wind barrel of heat exchanger, 26: Heat exchanger main body, 27: Fan, 3: Machine room, 33: Air conditioning cold air outlet, 4: Indoor air conditioner, 5: Fan for phase switching as forward and reverse switching control means Electromagnetic switch, 6:
Fan rotation speed control device, 7: Wind speed or wind pressure detection sensor.

Claims (1)

[Scope of Claims] 1. A cooling water circulation path is piped between an air/water heat exchanger equipped with a fan installed opposite to a cold air outlet of an indoor air conditioner and an object to be cooled on the heat load side, and the cooling water is While circulating cooling water through the water circulation path, the cold air blown out from the air conditioner is sucked and guided to the air/water heat exchanger by the fan operation of the heat exchanger to exchange heat with the cooling water. In a water-cooled cooling device that removes heat generated on the heat load side by dissipating retained heat into the air, the fan of the air/water heat exchanger is a reversible fan, and normal cooling operation is performed. Occasionally, the fan is operated in normal rotation to actively draw and guide air-conditioned cold air to the air/water heat exchanger, and when the cooling water temperature is quickly raised above the air-conditioned cold air temperature due to heat load operating conditions, the above-mentioned A water-cooled cooling device characterized by switching the fan to reverse operation to suppress the introduction of air-conditioned cold air to the air/water heat exchanger and reduce its heat dissipation capacity. 2. The water-cooled cooling device according to claim 1, comprising operation control means for switching the rotation direction of the fan installed in the air/water heat exchanger between forward rotation and reverse rotation based on a command. A water-cooled cooling device characterized by: 3. The water-cooled cooling device according to claim 2, characterized in that the heat collection control means has the functions of forward rotation and reverse rotation of the fan, and rotation speed control functions of the fan. Cooling system.