JP2007024488A - Cooler - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cooler capable of using a water coolant and capable of reducing an electric power consumption. <P>SOLUTION: This cooler 1 has a water coolant circulation part 1 constituted of an evaporator 21 built in with a heat exchanger 211 with a flowing heating medium to exchange heat with the water coolant, a condenser 24 for radiating a heat quantity of the water coolant to the atmosphere, the first pipe 23 having a compressing means 22 for compressing steam generated in the evaporator 21, and connected with an outlet of the evaporator 21 and an inlet of the condenser 24, and the second pipe 25 connected with an outlet of the condenser 24 and an inlet of the evaporator 21, and an evacuation means 3 for bringing the water coolant circulation part into vacuum pressure. The evacuation means 3 has the third pipe 31 connected to a lower side with respect to the evaporator 21, and having the water coolant with a height for forming a water head difference corresponding to vacuum pressure of a water coolant circulation part 2, a water supply means 33 for supplying water to the water coolant circulation part 2 and the third pipe 31, an exhaust means 35 communicating the water coolant circulation part 2 with the atmosphere, and a releasing means 34 for releasing the water coolant of the water coolant circulation part to the atmosphere. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a cooling device that uses water as a refrigerant for cooling a fluid to be cooled flowing out from various devices and uses a pipe line through which the water refrigerant circulates as a vacuum pipe.

  In various machine facilities, the fluid to be cooled is cooled to 10 to 30 ° C., for example. In Patent Document 1, as a device for cooling a fluid to be cooled to a medium to low temperature range of about 20 ° C. to 25 ° C., water is sprayed on a cooling unit and a cooling unit formed by stacking a plurality of heat transfer (cooling) pipes. A hermetic evaporative cooling tower having a watering device and a cooling fan that ventilates a cooling unit, and a cooler having a compressor, a condenser, an expansion valve, and an evaporator and circulating a refrigerant in this order in the same casing Provided integrally on the top and bottom, connecting the cooling unit and the evaporator so that the fluid to be cooled passes, and providing the fluid to be cooled first to the cooling unit and then to the evaporator and then to the outside At the same time, a cooling device having a temperature controller for controlling the operation and stop of the cooling tower and the cooler according to the temperature of the fluid to be cooled has been proposed and put into practical use. In this closed type cooling device, the temperature of the water sprayed to the cooling section does not rise even when the cooler is in operation, so the power consumption during operation of the cooler can be reduced, and if necessary, the bypass pipe can be opened to cool it. Since it passes through the evaporator without passing through the section and operates the switching valve on the compressor to reverse the refrigeration cycle and heats it with the evaporator, there is an advantage that it is possible to supply a fluid to be cooled at a constant temperature throughout the year.

  In existing cooling devices, in general, alternative chlorofluorocarbons (for example, substances with zero ozone depletion potential (ODP) such as HFC) are used as refrigerants in terms of cooling performance and environmental performance. Cooling devices using natural refrigerants (water, ammonia, propane, carbon dioxide, etc.) with a low coefficient (GWP) are being put into practical use. Among these natural refrigerants, water having zero GWP, excellent environmental properties and non-toxic water is most useful, but water has an evaporation pressure at 5 ° C. of 0.8718 kPa and other natural refrigerants (for example, ammonia). Then, it is low compared with 515.8 kPa at 5 ° C. Therefore, since a cooling (freezing) cycle is executed under a vacuum condition in a cooling device using water refrigerant, a structure for improving the cooling efficiency (for example, coefficient of performance: COP) in vacuum operation has been studied. .

  For example, in Patent Document 2, an evaporator and a condenser communicate with each other through two pipe lines to form a closed circulation line, and a compressor is accommodated in one pipe line and adjusted to the other pipe line. A valve is arranged, water is used as a cooling refrigerant, the inside of the evaporator is set to a temperature of 5 ° C., a pressure of 6.5 mmHg (0.8 kPa) to a temperature of 30 ° C., a pressure of 31.8 mmHg (4.2 kPa), and a condenser. A cooling device is described in which heat exchange is performed with the inside of a temperature range of 10 ° C., a pressure of 9.2 mmHg (1.2 kPa) to a temperature of 90 ° C., and a pressure of 525.8 mmHg (70.1 kPa). In this cooling device, when heat exchange is performed, for example, an exhaust port is provided in a part of the circulation line, and a vacuum pump is connected to the exhaust port for exhaustion, and the pressure in the circulation line is reduced to a substantially vacuum pressure. The water is lowered and filled into the evaporator.

  In Patent Document 3, in a vacuum ice making apparatus having a vacuum ice making unit, an absorption refrigerator, and a cooling circulation line, the vacuum ice making unit is maintained under a pressure condition of a triple point pressure of cold water or less of the supplied water. A vacuum ice-making container that evaporates a part of the water and freezes a part of the remaining water by the latent heat of the water evaporation, a compressor that compresses the water vapor evaporated in the vacuum ice-making container, and heat for cooling the water vapor provided therein It describes that it comprises a vacuum ice making unit side condenser that cools and condenses water vapor evaporated in a vacuum ice making container by an exchanger. In this vacuum ice maker, the inside of the ice maker is maintained in a vacuum by connecting a vacuum pump to the vacuum ice making unit side condenser.

  Patent Document 4 discloses an apparatus comprising a vapor compression refrigerator comprising an evaporator for introducing water vapor, a compressor, and a condenser incorporating makeup water, and a cooling tower for introducing cooling water to the condenser. Cold water is sent from the condenser to the path of the cooling water liquid level control means installed at each level of the building and a cooling radiation panel as a heat exchange means are interposed, one end of the cold water pipe is connected to the condenser, The other end is connected to the water vapor pipe through a cold water liquid level control means (ball tap type liquid level controller) and a heat exchange means (heat exchange coil), and the water vapor pipe passes through the heat exchange means and the cold water liquid level control means. A water refrigerant vaporization natural circulation cooling system is described which is connected to a cold water pipe and whose upper end is connected to the input side of the evaporator. In this water vapor compression refrigerator, a part of air contained in water vapor and water accumulated in a condenser is discharged by a vacuum pump.

Japanese Patent Publication No. 5-70069 (pages 2 and 3, FIG. 1) JP-A-11-257817 (page 3-4, FIG. 1) JP-A-7-280401 (page 5-6, FIG. 1) JP 2003-322423 (page 3-4, FIG. 1)

  In a cooling device in which water refrigerant is used, in order to make a circulation piping line into a vacuum, as described in Patent Documents 2 to 4, exhaust is generally performed using a vacuum pump. Further, according to the cooling device in which condensed water is discharged and supply water is supplied to the evaporator by that amount, it is necessary to exhaust non-condensable gas such as air entering along with the supply water. Is always operated. Therefore, when the vacuum pump is always operated, about 1/3 of the total power consumption of the cooling device is consumed, and the reduction is desired. Here, the non-condensable gas refers to a gas that does not condense under the temperature and pressure in the cooling device, and indicates, for example, air, oxygen, nitrogen, carbon dioxide, etc. dissolved in makeup water.

  Further, in a cooling device in which a vacuum pump is used, if the vacuum pump is driven when there is condensed water in the pipe system, failure due to penetration of the condensed water in the pipe can be considered.

An object of the present invention is to solve the above-described problems and provide a cooling device that uses a water refrigerant and that consumes less power than before.
Another object of the present invention is to provide a cooling device that solves the above problems and uses a highly reliable water refrigerant with few failures.

In order to achieve the above object, a cooling device of the present invention includes an evaporator containing a heat exchanger in which a heat medium flows and exchanges heat with a water refrigerant, a condenser that releases heat of the water refrigerant to the atmosphere, A first pipe having compression means for compressing water vapor generated in the evaporator and connected to an outlet of the evaporator and an inlet of the condenser; and an outlet of the condenser and an inlet of the evaporator are connected A second refrigerant pipe, a water refrigerant circulation section formed by:
A vacuum means for setting the water refrigerant circulation section to a vacuum pressure;
A cooling device comprising:
The vacuum means is
A third pipe connected to the lower side of the evaporator and having a height at which the water refrigerant forms a water head difference corresponding to the vacuum pressure of the water refrigerant circulation section;
Water supply means for supplying water to the water refrigerant circulation section and the third pipe;
An exhaust means for allowing the water refrigerant circulation part to communicate with the atmosphere;
Opening means for opening the water refrigerant in the water refrigerant circulation section to the atmosphere;
It is characterized by having.

  In the present invention, the opening means includes a first water tank that opens to the atmosphere, and an opening valve provided in the middle of the third pipe, the compression means is a turbo compressor, and the third pipe is Preferably, the exhaust means is an exhaust valve provided so that the water refrigerant circulation part and the atmosphere can communicate with each other.

  In the present invention, the condenser has a refrigerant coil having an inlet connected to the evaporator via the first pipe having the compression means, and an outlet connected to the evaporator via the second pipe; It is preferable to have watering means for water-cooling the refrigerant coil and air blowing means for blowing air to the refrigerant coil.

  According to the invention, the condenser has an inlet connected to the evaporator via the first pipe having the compression means, and an outlet connected to the evaporator via the second pipe. It can also be made to have any one of a refrigerant | coolant coil, the water spray means which water-cools the said refrigerant | coolant coil, and the ventilation means which ventilates the said refrigerant | coolant coil.

  In the present invention, it is desirable that the water refrigerant circulation unit has a volume capable of maintaining the vacuum of the water refrigerant circulation unit even when non-condensable gas is released from the water refrigerant.

  Further, in the present invention, at least a part of the water refrigerant circulation part and the vacuum means may be provided with a heating means to prevent freezing of each device when the operation is stopped at an outside temperature of 0 ° C. or less such as in winter. desirable.

According to the present invention, the piping system in which the water refrigerant circulates is made into a vacuum pressure by utilizing the water head difference, and the mass of the water refrigerant in the piping system is maintained because the piping system is formed by the sealed piping. Therefore, it is not necessary to supply makeup water to the evaporator, and it is not necessary to provide a vacuum pump for discharging non-condensable gas that enters with the makeup water, so that power consumption can be greatly reduced.
Further, according to the present invention, since it is not necessary to provide a vacuum pump itself for obtaining a vacuum, even if condensation in the pipe is generated inside the piping system, a failure due to intrusion of condensed water into the vacuum pump. It is possible to obtain a highly reliable cooling device that does not cause any of the above.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a cross-sectional view schematically showing a cooling device according to an embodiment of the present invention. The cooling device 1 is composed of a water refrigerant circulation part 2 in which water refrigerant such as tap water circulates as indicated by a broken line arrow, and a vacuum means 3 for evacuating the water refrigerant circulation part 2. The water-refrigerant circulation unit 2 includes an evaporator 21 that evaporates the water refrigerant that flows therein, and a condenser that is installed on the downstream side of the evaporator 21 via a first pipe 23 provided with compression means 22 in the middle thereof. 24 is a sealed flow path in which an outlet 242 of the condenser 24 and a second pipe 25 that connects the evaporator 21 in a sealed state are connected. The vacuum means 3 includes a third pipe 31 connected below the evaporator 21, a water supply means 33 for supplying water to the water refrigerant circulation unit 2 and the vacuum means 3, and an exhaust valve (exhaust means) provided in the water refrigerant circulation unit 2. ) 35 and an open valve (opening means) 34 provided at the end of the third pipe 31. The water-refrigerant circulation part 2 is made into a vacuum pressure by the vacuum means 3, and a cooling cycle, such as evaporation, compression, condensation, and expansion, is formed thereafter.

Details of each part of the cooling device are as follows.
(Water refrigerant circulation part)
The evaporator 21 is a sealed container in which water refrigerant flowing into the evaporator 21 evaporates to generate water vapor, and a heat exchanger formed of a coiled tube in which, for example, a heat medium (fluid to be cooled) flows. 211 is arranged. When water is used as the refrigerant, for example, in the use temperature range where the water refrigerant at 5 ° C. is obtained, it is necessary to evaporate the water at room temperature (5 ° C.). It is set to be 8718 kPa. Further, the outlet 212 of the evaporator 21 is connected to the condenser 24 via a first pipe 23 provided with a compression means 22 in the middle.

  In the present invention, water is used as a refrigerant. Since water has a low cooling capacity per unit volume and requires a high compression ratio, a turbo compressor is preferably used as the compression means 22. The turbo compressor imparts energy (increases pressure) to water vapor by the rotation of the impeller. For example, a centrifugal turbo compressor (one stage or multiple stages) in which the meridian surface at the exit of the impeller is perpendicular to the rotation axis. ) Can be used. Further, in order to smoothly discharge the water refrigerant inside the piping system when obtaining a vacuum, which will be described later, as shown in FIG. 1, the compression means 22 is disposed above the evaporator 21 so as not to form a liquid pool. It is desirable that

  The condenser 24 has a refrigerant coil 243 accommodated therein, and has a structure in which a blower 244 and a water spray pipe 245 are installed above the condenser coil 243. The refrigerant coil inlet 241 is connected to the first pipe 23, and the outlet 242 is connected to the evaporator 21 via the second pipe 25 including the pressure reducing / regulating valve 26 and the connecting pipe 27. The water spray pipe 245 has a plurality of water spray holes (not shown) on the side facing the refrigerant coil 243, and a water spray pump 246 is provided on the lower end side. The condenser 24 is provided with a supply pipe 249 having a float 247 at the tip and a supply valve 248 in the middle.

(Vacuum means)
The third pipe 31 is connected to the lower side of the evaporator 21, and the tip thereof is open to the atmosphere via the first water tank 32. A water supply means 33 including a water supply valve 331 and a water supply pipe 332 is provided at an intermediate portion of the third pipe 31 in order to supply water to the water refrigerant circulation section 2 and the vacuum means 3. An open valve 34 is provided in the vicinity of the open end of the third pipe 31 in order to open the water refrigerant inside the water refrigerant circulating unit 2. The length of the third pipe 31 is set such that the water refrigerant circulation unit 2 is provided at such a height that the degree of vacuum in the low vacuum region is obtained inside the water refrigerant circulation unit 2. Specifically, the water head difference h1 between the water surface of the water refrigerant inside the evaporator 21 and the water surface of the first water tank 32 is about 10 m (10% corresponding to the evaporation pressure of water of 5 ° C. when the evaporation temperature is 5 ° C.). .24m).

  The material constituting the piping system including the refrigerant coil 243, the first piping 23, the second piping 25, and the third piping 31 is a metal material having corrosion resistance since the refrigerant is water, such as austenitic stainless steel (SUS304, etc. ) Is preferably used. The refrigerant coil 243 can be formed of a bellows tube made of this kind of material. Since the gasket material (packing) is used in a vacuum region, it is preferable to use acrylonitrile butadiene rubber or chloroprene rubber having excellent mechanical properties (use temperature is 90 ° C. or less).

  Here, the principle of cooling by the cooling device 1 will be described with reference to FIGS. FIG. 2 shows a Mollier diagram (pressure-specific enthalpy diagram) in the case where a cooling cycle having an evaporation temperature of 5 ° C. and a condensation temperature of 40 ° C. is constructed using water as a refrigerant, and the vertical axis represents pressure (kPa). ), And the horizontal axis is specific enthalpy (kJ / kg). Each section in FIG. 2, that is, between point A and point B (first section), between point B and point C (second section), between point C and point D (third section), and between point D and point A In the (fourth section), a cooling cycle is configured corresponding to each process of evaporation, adiabatic compression, condensation, and expansion. Changes in the state of the water refrigerant in each section are as follows.

(First section)
The evaporator 21 is filled with, for example, 5 ° C. water refrigerant, and the water refrigerant circulating unit 2 including the evaporator 21 is operated at 0.87 kPa, which is the evaporation pressure of water at 5 ° C., by operating the vacuum means 3 described below. The vacuum pressure is set to At this time, the height h1 from the water surface of the first water tank to the upper surface of the water refrigerant in the evaporator 21 is 10.24 m at which a water pressure corresponding to the difference between the atmospheric pressure and the pressure in the evaporator 21 is obtained. . The water refrigerant starts to evaporate at point A in FIG. 2 and changes isothermally until the state of point B on the saturated vapor line (saturated steam) is reached by the evaporator 21. As described above, in the present invention, the above-described vacuum pressure fills the inside of the water refrigerant circulation unit 2 including the evaporator 21, the compressor 22, and the condenser 24 with a height of about 10 m below the evaporator 21. It is obtained by discharging the water refrigerant of the water refrigerant circulation section 2 from the third pipe 31 provided so as to have the outside. In FIG. 2, the point B is shown on the saturated steam line, but it is desirable to set the superheated steam (on the right side of the saturated steam line in the figure) in order to prevent water from entering the compression means 22.
(Second section)
The saturated steam in the state of point B is sent to the compression means 22 and adiabatically compressed by the compression means 22 until the evaporation pressure of water at 40 ° C. reaches 7.385 kPa, and the state of point C (high temperature (about 195 ° C.)) Superheated steam).
(3rd section)
The superheated steam in the state of point C is cooled by the condenser 24 and becomes a state of point D on the saturated liquid line at 7.385 kPa (completely liquefied and hot water of 40 ° C.). At this time, the water refrigerant in the evaporator 21 The height difference h2 between the water surface and the water surface of the water refrigerant in the second pipe is 0.66 m corresponding to the difference in vapor pressure between 5 ° C and 40 ° C. In FIG. 2, the point D is shown on the saturated liquid line, but in order to improve the coefficient of performance (COP), it is desirable to set it to supercooled water (left side of the saturated liquid line in the figure).
(4th section)
The hot water in the state of point D is decompressed to 0.8718 kPa which is the evaporation pressure of 5 ° C. water by the pressure reducing / regulating valve 26 and sent to the evaporator 21 to be in the state of point A (5 ° C. wet steam).
Thereafter, this cooling cycle is repeated.

By operating the cooling device configured as described above, for example, according to the following procedures (a), (b), and (c), the water refrigerant circulation unit 2 is brought into a vacuum pressure state and the cooling cycle can be executed. .
(A) With the open valve 34 closed and the piping system (water refrigerant circulation part 2) shut off from the atmosphere, the exhaust valve 35 is opened and the water supply valve 331 is opened for a predetermined time. By this operation, water is supplied from the water supply pipe 332, all the air in the piping system is released into the atmosphere from the exhaust valve 35, and the piping system is filled with the water pressure of the refrigerant (for example, 101.325 kPa or more).

(B) After the piping system is full, the water supply valve 331 and the exhaust valve 35 are closed, and the release valve 34 is opened. By the operation of closing and opening these valves, the water refrigerant circulating unit 2 is opened to the outside through the first water tank 32 that receives the end of the third pipe 31 connected to the lower side of the evaporator 21. At this time, the water surface above the water refrigerant descends from the exhaust valve 35, and the descent of the water surface stops at a position where the upper water surface descends to a position about 10 m higher than the water surface in the first water tank 32. This phenomenon occurs because the pressure of water in the piping system and the atmospheric pressure are balanced, and at this time, the inside of the closed flow path of the water refrigerant circulation unit 2 is in a vacuum state in a low vacuum region. The degree of vacuum obtained here depends on the water head difference h between the water surface in the first water tank 32 and the evaporator 21. If the water head difference h1 is set to 10.243 m, for example, the vacuum is theoretically 0.8718 kPa. . At this time, since the non-condensable gas such as air contained in the water refrigerant is released to the water refrigerant circulation unit 2, the water non-condensable gas is reduced in order to lower the partial pressure of the released non-condensable gas and reduce its influence. It is desirable to make the internal volume of the refrigerant circulation part 2 sufficiently large, and the exhaust valve 35 can be arranged so as to have a predetermined height from the first pipe 23.

(C) Next, the heat medium (for example, water to be cooled at 12 ° C.) discharged from the external device 4 is introduced into the heat exchanger 211 in the evaporator 21 while the compression unit 22 is driven, and the condenser 24 is provided. By driving the blower 244 and the watering pump 246, a cooling cycle such as evaporation, compression, condensation, and expansion of the water refrigerant is performed and the heat medium is cooled as follows.

  In the evaporator 21, when the water evaporates (the evaporation temperature of water is 5 ° C.), water vapor (vapor pressure is 0.8718 kPa) is generated, and cold water of about 5 ° C. is accumulated inside. This water vapor is compressed by the compression means 22 (for example, a pressure increase of 7.375 kPa is given) and sent to the condenser 24. In the condenser 24, cold water is sprayed on the cooling coil 243 from the upper part of the sprinkling pipe 245, and the water refrigerant is cooled by the latent heat of vaporization, and is also cooled by the outside air introduced by the blower 244. In this case, the sprinkled cooling water sequentially falls to the lower cooling pipe while forming a water film on the outer peripheral surface of the cooling pipe, and the water refrigerant in the cooling pipe is cooled. The cold water sprayed on the cooling coil is supplied from the supply pipe 249, and then the foreign matter is removed by a strainer (not shown) and then pumped up by the watering pump 246. Finally, the water vapor is cooled and liquefied to become 40 ° C. warm water, which is reduced in pressure through the second pipe 25 including the pressure reducing / regulating valve 26 and the connecting pipe 27 and returns to the evaporator 21.

  In the process of repeating the above cooling cycle, in the evaporator 21, the water to be cooled (for example, 12 ° C.) flowing from the external device 4 is cooled by heat exchange with the water refrigerant (for example, 5 ° C.) obtained above. And returned to the external device 4 (for example, 7 ° C.).

  FIG. 3 is a schematic cross-sectional view schematically showing a cooling device according to the second embodiment of the present invention. The same functional parts as those in FIG. This cooling device 1 ′ has the same structure as that of FIG. 1 except that the watering means (watering pipe 245, water supply pipe 249 and their attached devices) is omitted in the condenser 24 of FIG. 1 and the cooling coil 243 is air-cooled. Have According to this structure, since the number of parts of the condenser 24 can be reduced, a low-cost device can be obtained. Further, according to the cooling device 1 ′, the cooling capacity is slightly lower than that of the water-cooled type, but since the scale does not adhere to the cooling coil 243, there is an advantage that maintenance inspection becomes easy. According to this cooling device, the operation can be performed by the same operation as the cooling device shown in FIG.

  1 and 3 uses water refrigerant, it is necessary to prevent the water refrigerant from freezing at the time of operation stop when the outside air temperature is 0 ° C. or lower, such as in winter. 22, it is desirable to perform a heat insulation process (heat insulation process) on the water refrigerant circulation section 2 formed by the first pipe 23 and the second pipe 25 connecting the condenser 24 and each device and at least a part of the vacuum means 3. . Furthermore, it is more desirable to provide heating means (not shown) for preventing each of the above devices from becoming 0 ° C. or lower.

(Experimental example)
The operation of the cooling device of the present invention was confirmed by independently producing the water refrigerant circulation part 2 and the vacuum means 3 and carrying out a confirmation test of each operation.
First, the operation confirmation test of the vacuum means will be described. 4 is a test apparatus in which only the vacuum means 3 is extracted from the cooling device 1 shown in FIG. That is, this test apparatus is composed of an exhaust valve 35 ′, a virtual water refrigerant circulation part 2 ′, a third pipe 31, an open valve 34, and a first water tank 32 from above, and a water supply valve is provided in the middle part of the third pipe 31. A water supply pipe 332 is connected via 331. The installation height h of the exhaust valve 35 ′ is 13.4 m above the water surface of the first water tank 32. Further, a vacuum gauge 36 is connected to the virtual water refrigerant circulation section 2 ′.

Using this test apparatus, a confirmation test was performed according to the following procedure.
1. The water supply valve 331 is opened with the exhaust valve 35 ′ and the open valve 34 opened, and water is supplied from the water supply pipe 334 to the first water tank 32 until the open valve 34 is completely immersed.
2. In this state, the open valve 34 is closed, and water supply is continued until the third pipe 32 and the virtual water / refrigerant circulation unit 2 ′ are full. At this time, the air in the third pipe 32 and the virtual water / refrigerant circulation part 2 ′ is discharged to the atmosphere from the exhaust valve 35 ′, so that the inside of the pipe below the exhaust valve 35 ′ is filled only with water.
3. Next, when the release valve 34 is opened, as a result, the water below the exhaust valve 35 ′ is discharged to the outside through the release valve 34 and the first water tank 32, so that the water level in the pipe is accumulated in the first water tank 32. It descends from the surface of the water thus obtained until it reaches the height of h1.
4). At this time, the pressure of the virtual water refrigerant circulation section 2 ′, the water level h <b> 1 upward from the water surface of the first water tank 32, and the pressure value of the vacuum gauge 36 are confirmed.

  As a result of the confirmation test, it was confirmed that the pressure of the virtual water refrigerant circulating part 2 ′ was 2 kPa to 4 kPa, a vacuum pressure was obtained, and that the water level h2 at this time was 10.33 m to 10.54 m. At this time, a boiling phenomenon was confirmed near the water surface. From this, it was confirmed that the vacuum pressure necessary for boiling water at room temperature (27 ° C.) without using a vacuum pump was obtained.

Next, the operation confirmation test of the water refrigerant circulating unit will be described. The test apparatus shown in FIG. 5 has the same configuration as the cooling apparatus shown in FIG. 1 except that it includes a vacuum pump 3 ′ instead of the vacuum means 3 of the cooling apparatus shown in FIG. 1 and omits the exhaust valve 35. is there. In this test apparatus, an evaporator having an internal volume of 0.21 m ³ and storing water refrigerant therein, a compressor with a compressor output of 2.2 kW, a vacuum pump with an exhaust speed of 8.5 m ³ / h, and a heat of condensation A confirmation test was carried out using a 4.85 kW condenser according to the following procedure.
1. The vacuum pump 3 ′ is driven in a state where the water refrigerant is put in the evaporator 21, the water refrigerant circulation unit 2 is vacuumed at 0.8718 kPa, and the vacuum pump 3 ′ is stopped.
2. The compressor 22 is driven.
3. The pressure inside the evaporator 21 and the temperature of the water refrigerant are confirmed.

As a result of the above confirmation test, once the water refrigerant circulation unit 2 is vacuumed to 0.8718 kPa by the vacuum pump 3 ′, the vacuum state is maintained even after the operation of the compressor 22 is started. It was confirmed that water (0.21 m ³ ) inside 21 was cooled to 17.0 ° C. to 4.6 ° C.

  As a result of the above-mentioned two confirmation tests, a cooling device that does not require the use of a vacuum pump can be obtained by using a vacuum means utilizing a water head difference and configuring the water refrigerant circulation part with a sealed pipe. I was able to confirm.

It is a schematic sectional drawing of the cooling device concerning the 1st Embodiment of this invention. It is a Mollier diagram (pressure-specific enthalpy diagram (5-40 ° C.)) of a water refrigerant. It is a schematic sectional drawing of the cooling device concerning the 2nd Embodiment of this invention. It is a schematic sectional drawing which shows the confirmation test apparatus of a vacuum means. It is a schematic sectional drawing which shows the confirmation test apparatus of a water refrigerant circulation part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1 ': Cooling device 2: Water refrigerant circulation part 2': Virtual water refrigerant circulation part 21: Evaporator 211: Heat exchanger 22: Compression means (compressor)
23: first piping 24: condenser, 241: inlet, 242: outlet, 243: cooling coil, 244: blower, 245: watering pipe, 246: watering pump, 247: float, 248: supply valve, 249: supply pipe 25: second pipe 26: pressure reducing / regulating valve 27: connecting pipe 3: vacuum means, 3 ': vacuum pump 31: third pipe 32: first water tank 33: water supply means, 331: water supply valve, 332: water supply pipe 34 : Open valve 35, 35 ': Exhaust valve 4: External equipment

Claims (5)

An evaporator having a built-in heat exchanger in which a heat medium flows and exchanges heat with water refrigerant; a condenser that releases heat of the water refrigerant to the atmosphere; and compression means that compresses water vapor generated in the evaporator A water refrigerant circulation section formed by a first pipe to which the outlet of the evaporator and the inlet of the condenser are connected, and a second pipe to which the outlet of the condenser and the inlet of the evaporator are connected. When,
A vacuum means for setting the water refrigerant circulation section to a vacuum pressure;
A cooling device comprising:
The vacuum means is
A third pipe connected to the lower side of the evaporator and having a height at which the water refrigerant forms a water head difference corresponding to the vacuum pressure of the water refrigerant circulation section;
Water supply means for supplying water to the water refrigerant circulation section and the third pipe;
An exhaust means for allowing the water refrigerant circulation part to communicate with the atmosphere;
Opening means for opening the water refrigerant in the water refrigerant circulation section to the atmosphere;
A cooling device comprising: The opening means includes a first water tank that opens to the atmosphere, and an opening valve provided in the middle of the third pipe,
The compression means is a turbo compressor,
The third pipe has a height that forms a water head difference corresponding to the evaporation pressure of water,
The cooling device according to claim 1, wherein the exhaust unit is an exhaust valve provided so that the water refrigerant circulation unit and the atmosphere can communicate with each other. The condenser is
A refrigerant coil having an inlet connected to the evaporator via the first pipe having the compression means, and an outlet connected to the evaporator via the second pipe;
Watering means for water cooling the refrigerant coil and / or air blowing means for blowing air to the refrigerant coil;
The cooling device according to claim 1, wherein: The cooling device according to any one of claims 1 to 3, wherein the water refrigerant circulation unit has a volume capable of maintaining a vacuum even when non-condensable gas is released from the water refrigerant. The cooling device according to any one of claims 1 to 4, wherein a heating unit is provided in at least a part of the water refrigerant circulation unit and the vacuum unit.

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