JPH11351685A - Cooling system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cooling system having an excellent economy field in the system of a clean room, a computer room or the like required for cooling at a predetermined room temperature year-round. SOLUTION: The cooling system 10 comprises an air-cooled condenser 12B using an atmosphere and a water-cooled condenser 12A using a cooling water in parallel as a condenser 12, and a controller 24 for controlling opening/closing valves 26, 28, a fan 42, a cooling water supply source 32 and a pump 34 based on an atmospheric temperature measured by an atmospheric thermometer 44, thereby selecting the condenser 12 used for condensing the refrigerant.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling system, and more particularly to a cooling system such as a clean room or a computer room which is required to cool to a constant room temperature throughout the year.

[0002]

2. Description of the Related Art In a cooling system in which a room is indirectly cooled by a refrigerant such as chlorofluorocarbon or the like, an evaporator is installed on the side of a room to be cooled, a condenser is installed on a cold heat source side, and an evaporator and a condenser are installed. A closed system circulation path is formed between them. A refrigerant such as chlorofluorocarbon is sealed in the circulation path, and the refrigerant is circulated between the evaporator and the condenser to cool air supplied to the room to be cooled. That is, the liquefied refrigerant condensed by the condenser is evaporated by the evaporator, and at that time, the cooling is performed by removing latent heat of evaporation from the air supplied to the room to be cooled.

[0003]

However, in the conventional cooling system, since the refrigerant is condensed by cooling with the cooling water, the consumption of the cooling water used in the condenser is large and the running cost is high. There were drawbacks.
In particular, when annual cooling of a computer room or the like is required, cooling water must be supplied at all times, so that the running cost has become extremely large.

[0004] The present invention has been made in view of such circumstances, and has as its object to provide a cooling system that is economically excellent.

[0005]

In order to achieve the above object, the present invention circulates a refrigerant in a circulation path connecting an evaporator installed on the room to be cooled and a condenser installed on the cold heat source side. Then, in the cooling system that cools air supplied to the room to be cooled by evaporating the refrigerant condensed in the condenser in the evaporator, the condenser is supplied from cooling water supply means. A water-cooled condenser that cools and condenses the refrigerant with cooling water, and an air-cooled condenser that cools and condenses the refrigerant with outside air supplied from outside air supply means are provided in parallel with the evaporator. It is characterized by being able to.

According to the present invention, an air-cooled condenser utilizing outside air and a water-cooled condenser utilizing cooling water are arranged side by side with respect to the evaporator, and the air-cooled condenser and the water-cooled condenser are arranged side by side. on the other hand,
Alternatively, both were used as condensers. For example, when the outside air used for the air-cooled condenser is lower than the predetermined temperature range, only the air-cooled condenser is used, and when the outside air is higher than the predetermined temperature range, only the water-cooled condenser is used. When the outside air is within a predetermined temperature range, both the air-cooled condenser and the water-cooled condenser are used.
As a result, the consumption of cooling water used for the water-cooled condenser can be reduced as a whole system, so that the running cost can be reduced. Further, in the present invention, by using the air-cooled condenser and the water-cooled condenser as described above, the condensation capacity of the condenser can be stabilized regardless of the outside air temperature, and the cooling in the room to be cooled can be stabilized. Can be done.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a cooling system according to the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a system diagram of a cooling system 10 according to the present invention. The duct 20 communicates with the room to be cooled, and the duct 40 communicates with the outside air.

As shown in FIG. 1, in a cooling system 10, a condenser 12, a liquid pipe 14, an evaporator 16 and a steam pipe 18 are provided.
Thus, a closed circulation circuit is formed. A refrigerant such as chlorofluorocarbon is sealed in the circulation path, and the refrigerant evaporates in the evaporator 16 and condenses in the condenser 12, thereby circulating in the circulation path. The evaporator 16
Installed on the side of the room to be cooled, and in particular, a plurality of evaporators 16, 16,.
Are required, they are juxtaposed as shown in FIG. That is, the liquid pipe 14 branches at the branch portion 14b and branches into pipes 14a, 14a,.
Are connected to the evaporators 16, 16,... Respectively, and branch pipes 18a, 18a,... Of the steam pipes 18 connected to the respective evaporators 16, 16,.

The evaporator 16 is configured to evaporate the liquefied refrigerant sent through the liquid pipe 14 so as to remove latent heat of evaporation from the air in the room to be cooled. For example, like the evaporator 16 on the left side in the figure, the evaporator 16 is installed in a duct 20 communicating with the room to be cooled, and the air in the room to be cooled blown by the fan 22 passes through the inside of the evaporator 16. It is configured to Thus, the refrigerant evaporates in the evaporator 16 by removing latent heat of evaporation from the air in the room to be cooled, so that the air in the room to be cooled is cooled.

The fan 22 is configured to be able to adjust the flow rate of air to be blown, and is connected to a control device 24 via a signal cable. Control device 24
Is connected via a signal cable to a room temperature meter 30 for measuring the room temperature in the room to be cooled, and a signal of the room temperature is output from the room thermometer 30 to the control device 24. Control device 2
When the room temperature signal is output, the air conditioner 4 controls the fan 22 to adjust the air flow rate so that the room temperature becomes a preset target temperature.

On the other hand, the condenser 12 is installed above the evaporator 16, and is provided with a vapor pipe 18 and a liquid pipe 14.
It communicates with 6. As a result, the refrigerant gas evaporated in the evaporator 16 is spontaneously sent to the condenser 12 as an ascending airflow, and the liquefied refrigerant condensed in the condenser 12 is spontaneously sent to the evaporator 16 as a flowing liquid. You. The condenser 12 is configured by juxtaposing a water-cooled condenser 12A and an air-cooled condenser 12B. That is, the steam pipe 18 and the liquid pipe 14 are each branched into two, one of which is connected to the water-cooled condenser 12A,
The other is connected to the air-cooled condenser 12B. The steam pipes 18 after branching are provided with an on-off valve 26 and an on-off valve 28, respectively. The on-off valve 26 and the on-off valve 28 are respectively
It is connected to the control device 24 via a signal cable, and opens and closes when a signal is output from the control device 24 to open or close the steam pipe 18.

The water-cooled condenser 12A cools and condenses the refrigerant gas with cooling water. The cooling water used for the water-cooled condenser 12A is supplied from the cooling water supply source 32 to the water-cooled condenser 12A by driving the pump 34. The water-cooled condenser 12A is provided with a three-way valve 36 on the supply side of the cooling water, and the flow rate of the supplied cooling water can be adjusted by adjusting the valve opening. The cooling water supply source 32, the pump 34, and the three-way valve 36 described above are connected to the control device 24 via a signal cable.
4 controls the operation or stop of the cooling water supply source 32 and the pump 34 and the opening degree of the three-way valve 36.

The air-cooled condenser 12B is configured to cool and condense the refrigerant gas using outside air. That is, the air-cooled condenser 12B is installed in the duct 40 communicating with the outside air, and is configured such that the outside air blown by the fan 42 passes outside the pipe (not shown) through which the refrigerant gas passes. You. Thereby, the refrigerant gas is cooled and condensed by the outside air flowing outside the pipe.

The fan 42 is configured to adjust the flow rate of the blown air, and is connected to the controller 24 via a signal cable. Duct 40 upstream of fan 42
Inside, an outside air thermometer 44 for measuring the temperature of outside air is provided. The outside air thermometer 44 is connected to the control device 24 via a signal cable, and an outside air temperature signal is output from the outside air thermometer 44 to the control device 24.

When the outside air temperature signal is output, the control device 24 compares the outside air temperature with a predetermined temperature range set in advance.
8. Control the cooling water supply source 32, the pump 34, and the fan 42. That is, when the outside air temperature is lower than the predetermined temperature range, the control device 24 opens the on-off valve 28 and closes the on-off valve 26, and simultaneously operates the cooling water supply source 32 and the pump 34.
Is stopped and the fan 42 is driven. Conversely, when the outside air temperature is higher than the predetermined temperature range, the on / off valve 28 is closed and the on / off valve 26 is opened, and the cooling water supply source 32 and the pump 34 are driven to stop the fan 42. Further, when the outside air temperature is within a predetermined temperature range, the on-off valve 26
The opening and closing valve 28 is opened, and the cooling water supply source 32, the pump 34 and the fan 42 are driven. Thereby, when the outside air temperature is relatively low, the consumption of the cooling water can be reduced. Note that the predetermined temperature range is determined by the temperature of the cooling water to be used and the like.
At this time, the temperature is set to 7 ° C. to 15 ° C.

The control device 24 also controls the three-way valve 36 and the fan 42 based on the outside air temperature measured by the outside air thermometer 44.
To control the amount of cooling water sent to the water-cooled condenser 12A and the amount of outside air sent to the air-cooled condenser 12B. For example, when the outside air temperature is lower than a predetermined temperature range, the outside air amount is reduced when the outside air temperature decreases, and the outside air amount is increased when the outside air temperature increases. Further, when the outside air temperature is within a predetermined temperature range,
When the outside air temperature decreases, the outside air amount and the cooling water amount are reduced, and when the outside air temperature increases, the outside air amount and the cooling water amount increase. Thereby, it is possible to suppress a change in the condensation capacity of the condenser 12 caused when the outside air temperature changes.

Next, the operation of the cooling system 10 configured as described above will be described. In the cooling system 10,
The refrigerant circulates in a circulation path formed by the condenser 12, the liquid pipe 14, the evaporator 16, and the steam pipe 18. That is, the refrigerant evaporates into the refrigerant gas by removing the latent heat of evaporation from the air in the room to be cooled in the evaporator 16. This refrigerant gas is
Air is naturally supplied to the condenser 12 installed above via the steam pipe 18, and is cooled and condensed in the condenser 12 by outside air or cooling water. Then, the liquefied refrigerant is spontaneously sent to the lower evaporator 16 via the liquid pipe 14 and evaporates again in the evaporator 16. When the refrigerant circulates in the circulation path in this way,
The air in the room to be cooled is deprived of latent heat of evaporation when the refrigerant evaporates, and is cooled. The cooled air is sent to the room to be cooled by the fan 22, and the room to be cooled is cooled. As described above, since the flow rate of the fan 22 is adjusted by the controller 24 so that the room temperature of the room to be cooled becomes the preset target temperature, the room to be cooled is reliably cooled to the target temperature.

In the cooling system 10, a water-cooled condenser 12A and an air-cooled condenser 12B are provided side by side as the condenser 12, and the operation thereof is controlled by a controller 24. The controller 24 controls the condenser 12 for condensing the refrigerant.
Are switched as follows according to the outside air temperature. First, when the outside air temperature is higher than a predetermined temperature range, the refrigerant gas is condensed only by the water-cooled condenser 12A. That is, the control device 24 opens the on-off valve 26 to send the refrigerant to the water-cooled condenser 12A, and also supplies the cooling water supply source 32 and the pump 34
To supply cooling water to the water-cooled condenser 12A. As a result, the refrigerant gas is cooled and condensed by the cooling water in the water-cooled condenser 12A.

Next, when the outside air temperature is lower than the predetermined temperature range, the operation of the water-cooled condenser 12A is stopped, and the refrigerant gas is condensed only by the air-cooled condenser 12B. That is, the controller 24 opens the on-off valve 28 to send the refrigerant gas to the air-cooled condenser 12B, and supplies the outside air to the air-cooled condenser 12B by the fan 42. Thereby, the refrigerant gas is cooled by the low-temperature outside air and condensed. When the outside air is at a low temperature, the refrigerant gas can be sufficiently condensed only by the air-cooled condenser 12B, and the operation of the water-cooled condenser 12A is stopped. That is, the control device 24
Closes the on-off valve 26 to stop the supply of the refrigerant gas to the water-cooled condenser 12A, and stops the cooling water supply source 32 and the pump 34 to stop the supply of the cooling water. Thereby, the consumption of the cooling water can be suppressed, and the cost can be reduced.

When the outside air temperature is within a predetermined temperature range, both the water-cooled condenser 12A and the air-cooled condenser 12B are used. That is, the control device 24 opens the on-off valve 26 and the on-off valve 28, and supplies the cooling water supply source 32 and the pump 3
4 and the fan 42 are driven. Thereby, the refrigerant gas is cooled and condensed by the cooling water and the outside air. As described above, since the refrigerant is condensed by using both the water-cooled condenser 12A and the air-cooled condenser 12B, the water-cooled condenser 12A
It is possible to suppress fluctuations in the condensation capacity of the condenser 12 that occur when switching between the operation of the condenser A and the operation of the air-cooled condenser 12B.
When the outside air temperature is within a predetermined temperature range, the water-cooled condenser 12A and the air-cooled condenser 12B have almost the same condensation capacity. Accordingly, when the difference between the two condensing capacities becomes remarkably large, for example, as in the case where the air-cooled condenser 12B is continuously used even when the outside air temperature is higher than a predetermined temperature range, the cooling effect of the cooled room is maintained. Does not rise, and the room temperature of the room to be cooled does not become unstable.

The control device 24 not only switches the condenser 12 for condensing the refrigerant as described above, but also uses the cooling water in accordance with a change in the outside air temperature when the air-cooled condenser 24 is used. And the supply of outside air is varied. That is, when the outside air temperature rises, the control device 24
The supply amount of the cooling water or the outside air is increased by increasing the valve opening of the direction valve or increasing the amount of air blown by the fan 22. Conversely, when the outside air temperature decreases, the supply amounts of the cooling water and the outside air are reduced. Thus, it is possible to suppress a change in the condensation capacity of the condenser 12 due to a change in the outside air temperature, and to provide a stable cooling system.

As described above, in the cooling system 10, since the water-cooled condenser 12A and the air-cooled condenser 12B are used side by side, the consumption of the cooling water used for the water-cooled condenser 12A can be reduced. it can. Thereby, the running cost of the cooling system 10 can be reduced. In addition, the cooling system 10 determines the condenser 12 to be used for condensing the refrigerant based on the outside air temperature, and also supplies the amount of cooling water sent to the water-cooled condenser 12A or the air to the air-cooled condenser 12B according to the outside air temperature. Since the amount of outside air to be controlled is adjusted, it is possible to suppress a change in the condensation capacity of the condenser 12 due to the outside air temperature. Therefore, the refrigerant gas can be stably condensed, and a reliable cooling system can be provided.

In the above-described embodiment, the fan 22
Although the room temperature of the room to be cooled was adjusted by adjusting the amount of air blown, an electric valve was provided on the branch pipe 14a of the liquid pipe 14,
The valve opening may be adjusted. Thereby, the evaporator 16
Since the flow rate of the liquefied refrigerant fed into the inside can be adjusted, the room temperature of the room to be cooled can be adjusted. Further, instead of adjusting the amount of cooling water sent to the water-cooled condenser 12A or the amount of outside air sent to the air-cooled condenser 12B, the valve opening of the on-off valve 26 or the on-off valve 28 may be adjusted. .

In the above-described embodiment, cooling of the room to be cooled is performed. However, the condenser 12 and the evaporator 16 may be installed in reverse to perform heating. For example, a water-cooled condenser 12A
A hot water supply source is provided instead of the cooling water supply source 32, and the water-cooled condenser 12A is installed below the evaporator 16.
Thereby, the refrigerant is evaporated by the hot water supplied from the hot water supply source in the water-cooled condenser 12A, condensed by the evaporator 16 installed on the room side, and heats the room.

In the above embodiment, the condenser 1
2 is installed above the evaporator 16 and described in the example of the natural circulation cooling system in which the refrigerant is naturally circulated. However, the present invention is not limited to this, and the refrigerant may be circulated using a fan or a pump. The air-cooled condenser 12B is not limited to the structure described above, but may be provided with a water spraying unit to spray water on the outer surface of a pipe through which the refrigerant flows. Thereby, while the outside air is cooled by the sprayed water,
Since the sprayed water evaporates and deprives the refrigerant gas of latent heat of evaporation, the refrigerant can be more effectively condensed.

[0026]

As described above, in the cooling system according to the present invention, a water-cooled condenser using cooling water and an air-cooled condenser using outside air are juxtaposed, and the condenser to be used is kept at the outside air temperature. In addition to the above-mentioned determination, the condensation capacity of the condenser is adjusted in accordance with the fluctuation of the outside air temperature, so that the consumption of the cooling water can be reduced and the room can be stably cooled. As a result, running costs can be reduced, and a cooling system that is economically excellent can be provided.

[Brief description of the drawings]

FIG. 1 is a system diagram of a cooling system according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Cooling system 12 ... Condenser 12A ... Water-cooled condenser 12B ... Air-cooled condenser 14 ... Liquid pipe 16 ... Evaporator 18 ... Steam pipe 24 ... Control device 26 ... On-off valve 28 ... On-off valve 30 ... Indoor thermometer 44 … Outside air thermometer

Continued on the front page (72) Inventor Junta Hirata 1-11-1 Uchikanda, Chiyoda-ku, Tokyo Inside Hitachi Plant Construction Co., Ltd. (72) Inventor Noboru Oshima 1-1-1-1 Uchikanda, Chiyoda-ku, Tokyo Hitachi Plant Construction Co., Ltd.

Claims (6)

[Claims] A refrigerant is circulated in a circulation path connecting an evaporator installed on the side of a room to be cooled and a condenser installed on the side of a cold heat source, and the refrigerant condensed in the condenser is evaporated. In a cooling system that cools air supplied to the room to be cooled by evaporating the inside of the container, the condenser is a water-cooled condenser that cools and condenses the refrigerant with cooling water supplied from cooling water supply means. And an air-cooled condenser for cooling and condensing the refrigerant by external air supplied from external air supply means, and an air-cooled condenser provided in parallel with the evaporator. 2. An outside air temperature measuring means for measuring a temperature of outside air supplied to the air-cooled condenser; and a water-cooled condenser and / or an air-cooled condenser based on a temperature measured by the outside air temperature measuring means. And control means for switching control of the operation, wherein the control means controls both the water-cooled condenser and the air-cooled condenser when the measured temperature of the outside air temperature measuring means is within a predetermined temperature range. And operating only the air-cooled condenser when the temperature is lower than the predetermined temperature range, and operating only the water-cooled condenser when the temperature is higher than the predetermined temperature range. Cooling system. 3. The water-cooled condenser is provided with a water amount adjusting means for adjusting a flow rate of cooling water supplied to the water-cooled condenser, and the air-cooled condenser is provided with the air-cooled condenser. Air amount adjusting means for adjusting the flow rate of the supplied outside air is provided, and the control means controls the water amount adjusting means or the air amount adjusting means based on a temperature measured by the outside air temperature measuring means, and The cooling system according to claim 1, wherein a flow rate of the cooling water or the outside air is adjusted. 4. The condenser is installed above the evaporator, and the refrigerant evaporated in the evaporator is sent to the condenser as an ascending airflow, and the refrigerant condensed in the condenser is discharged. 4. The cooling system according to claim 1, wherein the liquid is sent to the evaporator as a flowing liquid. 5. A room temperature measuring means for measuring a temperature in the room to be cooled, a cooling amount adjusting means for adjusting a cooling amount of air in the room to be cooled by the evaporator, and a measurement temperature of the room temperature measuring means. The cooling system according to any one of claims 1, 2, 3 and 4, further comprising: a room temperature adjusting unit that controls the cooling amount adjusting unit based on the temperature and adjusts the temperature in the room to be cooled. 6. A water spraying means for spraying water is provided inside the air-cooled condenser, and the refrigerant is cooled by utilizing latent heat of evaporation of the water sprayed by the water spraying means. Item 5. The cooling system according to item 1, 2, 3, 4, or 5.