JP2580335B2 - Cooling system - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a cooling device using clathrate heat storage.

[Background Art] Conventionally, a so-called single-generation temperature heat storage system in which a single heat storage tank is used has been used even in a cooling device with an anti-AC refrigerant heat exchanger using a mixed refrigerant.

An example of such a cooling device will be described with reference to FIG.

In the figure, reference numeral 1 indicates a cooling device as a whole, and this cooling device 1 is composed of a primary cooling device 1a and a secondary cooling device 1b.

The primary side cooling device 1a is configured by being connected by a compressor 2, a condenser 3 as a heat exchanger, an evaporator 4, and a pipe 5 as a pipe route for circulating a refrigerant between these. ing. Further, the pipe 5 is provided with an expansion valve 6.

The secondary-side cooling device 1b includes a heat exchanger 7 for exchanging heat between a cooling load and cold water, and a heat storage tank 9 for keeping the heat storage water 8 at a constant temperature. 9 is
It is connected via a cold water cooling heat exchanger 10 for exchanging heat between the cold water and the heat storage water 8 in the heat storage tank 9. At this time, the heat exchanger 7 and the cold water cooling heat exchanger 10 are connected by a pipe 11 for circulating cold water and a circulation pump 12, and the heat storage tank 9 and the cold water cooling heat exchanger 10 circulate heat stored water. And a circulating pump 14.

The heat storage tank 9 and the evaporator 4 of the primary side cooling device 1a are connected by a pipe 15 as a pipe route for circulating a heat medium and a circulation pump 16.

In the cooling device 1 having such a configuration, the cold water heated by heat exchange with the outside air exchanges heat with the heat storage water 8 via the cold water cooling heat exchanger 10. The temperature of the heat storage water 8 in the heat storage tank 9 is maintained at a constant temperature by performing heat exchange with the primary side cooling device 1a through a pipe 15 for circulating a heat medium in the heat storage tank 9.

[Problems to be Solved by the Invention] In the conventional cooling device, the temperature of the heat medium exchanged with the heat storage water in the heat storage tank is determined by the temperature after use for generating the temperature in the heat storage tank (primary side cooling). Even at the temperature at the entrance of the device), the temperature must be lower than the temperature of the heat storage water in the heat storage tank.

Further, the heat storage water generation temperature in the heat storage tank is equal to or lower than the temperature obtained by subtracting the temperature difference required for heat exchange in the heat exchanger from the cold water utilization temperature.

For this reason, in the conventional apparatus using only the heat storage tank having a single generation temperature, for example, if the cold water use temperature is set to about 7 ° C., the heat storage water generation temperature in the heat storage tank becomes about 4 ° C. or outside, and the heat medium use temperature width is reduced. If the temperature is 6 ° C., the outlet temperature of the primary cooling device is -3.
If the temperature inside and outside of the primary cooling device is required and the primary cooling device outlet temperature is raised to within 0 ° C. to operate the primary cooling device, the heat medium circulation amount is doubled.

As a result, conventional cooling systems that use only a single-generation-temperature heat storage tank significantly impede the merits of anti-AC refrigerant heat exchangers that use a mixed refrigerant that aims to increase efficiency by stepwise chilled water cooling. Will do.

The present invention has been made in consideration of the above circumstances, and has as its object to provide a cooling device that utilizes the merits of a refrigerating machine with an alternating current refrigerant heat exchanger using a mixed refrigerant.

Means for Solving the Problems The cooling device of the present invention comprises a primary cooling device and a secondary cooling device, wherein the primary cooling device includes a compressor, a heat exchanger, and an evaporator. And a pipe path for circulating the refrigerant between them is connected. The secondary-side cooling device has a heat exchanger for performing heat exchange between the cooling load and the cold water, and the heat storage water is maintained at a constant temperature. A heat storage tank, wherein the heat exchanger and the heat storage tank are connected so that heat can be exchanged by a pipe route for circulating cold water, and the heat storage tank and the evaporator of the primary side cooling device are connected by a pipe route for circulating a heat medium. And a plurality of heat storage tanks having different temperatures of the heat storage water are provided.

[Action] When performing chilled water cooling using a heat storage tank, heat storage water is circulated in ascending order of heat storage temperature to one of the heat exchangers in the series for cooling water cooling, and the other heat exchanger , Cold water to be cooled is successively connected and flowed in a counter-current manner to cool the cold water stepwise.

Example An example of an example will be described below with reference to the drawings.

FIG. 1 shows an embodiment of a cooling device provided with two or more types of heat storage tanks having different generation temperatures.

The cooling device 20 of the present embodiment includes a primary cooling device 20a that circulates and cools a refrigerant, and a secondary cooling device 20b that cools cold water heated by a cooling load by heat exchange with heat storage water in a heat storage tank. It consists of

The primary-side cooling device is schematically configured such that a compressor 2, a condenser 3 as a heat exchanger, an evaporator 4, and a pipe 5 as a pipe route for circulating a refrigerant therebetween are connected.
Further, the primary side cooling device is provided with an expansion valve 6 for expanding the refrigerant.

The secondary-side cooling device 20b includes a heat exchanger 7 for exchanging heat between a cooling load and cold water, and two heat storage tanks 22 and 24 in which the heat storage waters 21 and 23 are each maintained at a constant temperature. Vessel 7
And the heat storage tanks 22 and 24 are connected so as to be able to exchange heat via two chilled water cooling heat exchangers 10 and 10. The heat storage tanks 22 and 24 and the evaporator 4 of the primary side cooling device 20a are provided with a heat medium. Circulating pipes15
Connected by

The heat storage tanks 22, 24 are heat storage water tanks for storing heat storage water,
Coolers and stirring pumps 22a and 24a are incorporated.

In the case of using the cooling device of this embodiment, the refrigerant is moved as shown by the arrow I by operating the expansion valve 6 in the primary cooling device in FIG. Then, the refrigerant is liquefied when passing through the condenser 3 and the compressor 2 and flows into the evaporator 4.

 This refrigerant is vaporized in the evaporator 4.

On the other hand, in the secondary-side cooling device 20b, the cold water warmed by heat exchange with air circulates in the pipe 11, passes through the cold-water cooling heat exchangers 10, 10, and is cooled.

The heat storage water 21 and 23 of the heat storage tanks 22 and 24 are
It circulates through 13, 14 and passes through heat exchangers 10, 10, where it is heated and exchanged with cold water. At the same time, heat storage tank 2
The pipes 15 exchange heat inside the pipes 2 and 24 to be cooled.

In the cooling device according to the present embodiment, the heat storage waters 21 and 23 whose generation temperatures are set to two different temperatures different from 4.7 and 7 ° C. 22 and 24 are provided.
Therefore, if the cold water use temperature is 7 ° C. and the heat medium use temperature width during heat storage is 6 ° C., the primary cooling device inlet temperature during heat storage is 6 ° C. and the outlet temperature is 0 ° C.

Thus, according to the cooling device of the present embodiment, compared with the conventional cooling device using only the heat storage tank for generating a single temperature,
The primary-side cooling device can be operated at a high evaporation temperature, and smooth stepwise refrigerant evaporation, which is an advantage of a counter-current refrigerant heat exchanger using a mixed refrigerant, is performed. Device) can be significantly improved.

Note that the cooling device of the present invention is not limited to the above embodiment, and other modifications are also possible.

For example, the temperature of the heat storage water in the heat storage tank is 4,
It is also possible to provide three different heat storage tanks at 6, 8 ° C., and in this case, if the cold water use temperature and the heat medium use temperature width during heat storage are the same as those in the above embodiment, the heat medium refrigerator inlet temperature Is 7
° C and the outlet temperature is 1 ° C, and the refrigerator can be operated at a higher evaporation temperature.

Further, the same effect can be obtained even if the pipe path for circulating the heat medium is provided not in one system but in the same number as the heat storage tanks and the primary cooling device is circulated. Further, when the primary cooling device has a plurality of evaporators or when the effect of the stepwise evaporation is high, it is possible to use different systems.

In addition, even when a plurality of different temperatures are desired to be used as the heat exchanger with the cooling load, the heat exchangers may be configured as independent systems.

“Effect of the Invention” The cooling device of the present invention includes a primary cooling device and a secondary cooling device. The primary cooling device includes a compressor, a heat exchanger, an evaporator, A pipe path for circulating the refrigerant is connected between the cooling device and the secondary-side cooling device includes a heat exchanger for performing heat exchange between the cooling load and the cold water, and a heat storage tank in which the heat storage water is maintained at a constant temperature. The heat exchanger and the heat storage tank are connected so that heat can be exchanged by a pipe route for circulating cold water, and the heat storage tank and the evaporator of the primary cooling device are connected by a pipe route for circulating a heat medium. Since the heat storage tank has a configuration in which a plurality of heat storage waters having different temperatures are provided, compared to a conventional cooling device using only a single temperature-generating heat storage tank, the refrigerator can be operated at a higher evaporation temperature. With the merits of an AC-type refrigerant heat exchanger that can operate and use a mixed refrigerant Some smooth stepwise refrigerant evaporation takes place,
Accordingly, the coefficient of performance of the refrigerator can be significantly improved.

[Brief description of the drawings]

FIG. 1 is an overall view showing a configuration of an embodiment of a cooling device of the present invention, and FIG. 2 is an overall view showing a configuration of a conventional example of a conventional cooling device. 1, 20 ... cooling device, 1a, 20a ... primary cooling device, 1b, 20b ... secondary cooling device, 9 ... heat storage tank.

Claims (1)

(57) [Claims] 1. A primary cooling device and a secondary cooling device, wherein the primary cooling device includes a compressor, a heat exchanger,
An evaporator and a pipe path for circulating a refrigerant are connected between the evaporators. The secondary-side cooling device has a heat exchanger that exchanges heat between a cooling load and chilled water, and heat storage water is maintained at a constant temperature. A heat storage tank, wherein the heat exchanger and the heat storage tank are heat-exchangeably connected by a pipe path for circulating cold water, and the heat storage tank and the evaporator of the primary cooling device are connected to a pipe path for circulating a heat medium. And a plurality of heat storage tanks having different temperatures of the heat storage water are provided.