JPH11257817A - Cooling system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cooling system having a simple configuration and high cooling efficiency by obtaining a large cooling effect by utilizing the latent heat of evaporation of water on an evaporator side and easily condensing steam to water on a condenser side. SOLUTION: In a cooling system, a closed circulating line 2 is constituted by connecting an evaporator 11 and a condenser 12 to each other through pipelines 13 and 14 and a compressor 17 is housed in the pipeline 13, and then, a regulating valve 19 is connected to the pipeline 14 and water is used as a coolant. The temperature and pressure for heat exchange in the evaporator 11 are adjusted between 5 deg.C and 30 deg.C and between 6.5 mmHg and 31.8 mmHg and those for heat exchange in the condenser 12 are adjusted between 10 deg.C and 90 deg.C and between 9.2 mmHg and 525.8 mmHg.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technology of a cooling apparatus in which an evaporator, a condenser and a compressor are arranged in a closed pipe and used for an air conditioner, a chiller, a refrigerator, and the like using water as a medium.

[0002]

2. Description of the Related Art Conventionally, those using chlorofluorocarbon, ammonia or the like as a cooling medium of a cooling device have been known. However, chlorofluorocarbon has been an environmental problem as a substance causing global warming and the like. Also, ammonia is toxic, corrosive,
Since it has problems such as odor, there are many problems to be solved in order to use it as a cooling medium. On the other hand, cooling has also been performed using water evaporation heat (evaporation latent heat) which is easily obtained and has high safety. However, at atmospheric pressure, water can evaporate only up to the saturated water vapor pressure with respect to the temperature in the air. By evaporating the water, the surrounding area decreases only by 4-5 ° C with respect to the temperature. As the humidity approaches 100%, the amount of evaporation decreases,
There has been a drawback that the cooling capacity is reduced and the humidity is increased to be humid. As a cooling device using this technique, there is a cooling fan or the like.

It is also known that the boiling point of water is lowered by lowering the pressure in a container containing water, and the water temperature is lowered by the latent heat of evaporation when the water is evaporated. For example, 5
When the temperature is lowered to ° C. and the water is boiled, the volume of the vapor when evaporated is 140,000 times the volume of the water. In other words, with 5 ° C water, the pressure is 6.539mmHg (about 870P
In the case of a), 1 cc of water becomes 147 liters of water vapor. The water vapor generated by this evaporator becomes 147 liters in 1 cc of water, and becomes 14.7 Kl in 100 g of water. Therefore, it is discharged by a piston type or gear type pump to discharge from the evaporator. In such a case, a large-capacity cylinder is required, and the exhaust efficiency is poor, which is uneconomical. In addition, if the cylinder is driven at a high rotation speed under the atmospheric pressure, the cylinder may be burned by resistance or the like. In the case of a compressor (pump) of a piston type, a gear type, a rotary type, etc., it is possible to compress a gas, but if water is compressed, it cannot be mechanically tolerated and may be broken. Had to be removed.

In heat pumps and refrigerators,
A technique for exchanging heat in an evaporator or a condenser using water as a refrigerant is also known. For example, JP-A-63-23
No. 1150 and Japanese Patent Application Laid-Open No. 7-280401.

[0005]

DISCLOSURE OF THE INVENTION The above-mentioned JP-A-63-23
In the technology of No. 1150, when the pressure is reduced to −610 mmHg at 60 ° C., water vapor is obtained by evaporating, and when the pressure is increased to 1 kg / cm ² G by a pump, the temperature is increased to 120 ° C. The heat can be recovered. In this case, water at 60 ° C is required at the evaporator,
Further, since the pressure needs to be compressed from -610 mmHg to 1 kg / cm ² G, a high driving force is required for the pump.

[0006] In the technique of Japanese Patent Application Laid-Open No. 7-280401, the temperature of the evaporator in the vacuum ice making section is set to 4.degree.
When the pressure is reduced to 5 Torr (4.5 mmHg), it reaches the boiling point and evaporates,
The pressure is increased by a centrifugal compressor to 10 Torr in a condenser, and the condensation temperature is set to 11 ° C. On the other hand, ice is produced in the evaporator part, and the condenser is cooled by circulating the refrigerant cooled in the absorption refrigerator. In this apparatus, it is shown that in a vacuum ice making section, a cooling cycle is constituted by compressing with a centrifugal compressor having a pressure ratio of 2.22, but in a condenser, it is necessary to lower the temperature to 11 ° C. However, it is not suitable for a cooling device such as an air conditioner, and it is necessary to always reduce the pressure of the condenser to 10 Torr by a vacuum pump, and a large capacity of the vacuum pump is required. The lower part of the vacuum ice making unit is connected to an ice heat storage tank that is opened to the atmosphere via a pump. Is difficult to maintain. In other words, it is difficult to seal with almost being in communication.

[0007] With respect to such a conventional technique, as described above, for example, when the pressure is 6.539 mmHg (about 870 Pa) at 5 ° C, 1 cc
Is 147 liters of water vapor. When this water vapor is compressed to 40 mmHg and brought into contact with an object at 30 ° C., the water vapor condenses and returns to 1 cc of water. Its temperature 30
At 25 ° C. and a pressure of 40 mmHg, the volume of water vapor is about 25 liters. The present invention focuses on this fact and constitutes a cooling device. That is, at this time, the volume ratio is about 1 /
6 (25/147), but the pressure difference is 40 mmHg-6.
5 mmHg = 33.5 mmHg (approximately 0.045 kgf / cm ² ), and it can be seen from the comparison that the atmospheric pressure is 1.033 kgf / cm ² that it is possible to compress with a small amount of power. That is, the present invention can provide a cooling device capable of performing cooling (cooling) efficiently by compressing with small power in a daily cooling temperature range.

[0008]

The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described. That is, the closed circulation line 2 is formed by connecting the evaporator 11 and the condenser 12 by the pipes 13 and 14, and the compressor 17 is provided in the pipe 13.
A cooling device in which a regulating valve 19 is disposed in the pipe line 14 and water is introduced into the circulation line 2 as a cooling refrigerant, wherein the inside of the evaporator 11 has a temperature of 5 ° C. and a pressure of 6.5 mmHg to 30. ℃, pressure 31.8mmHg range, the inside of the condenser 12 temperature 10 ℃, pressure 9.2mmHg ~ temperature 90 ℃, pressure 525.8mmH
The heat exchange is performed in the range of g. Also, the compressor 17 is configured so that the space between the suction side and the discharge side is not sealed. In addition, the compressor 1
7 is constituted by an axial fan or a screw fan.

[0009]

FIG. 1 is a view showing an example of a cooling apparatus according to the present invention. In the cooling apparatus 1 according to the present invention, an evaporator 11 and a condenser 12 are communicated with each other by a pipe 13 and a pipe 14, and These are sealed. A heat exchanger 15 is arranged in the evaporator 11, and a heat exchanger 16 is arranged in the condenser 12. A compressor 17 is arranged in the middle of the pipe 13, and a regulating valve 19 is arranged in a middle of the pipe 14. The regulating valve 19 regulates the flow rate of water. The regulating valve 19 may be an on-off valve that opens when a predetermined amount of water runs out in the evaporator 11 and closes when the evaporator 11 reaches a set water level.
Note that the compressor 17 does not isolate the pipe 13, and when the compressor 17 is not driven, the communication between the evaporator 11 and the condenser 12 is established.

Further, it is also possible that one or both of the heat exchangers 15 and 16 are not water-cooled but air-cooled. In this case, fins 22 are provided around the container of the evaporator 11 or the condenser 12 to increase the surface area to promote heat exchange. For example, as shown in FIG. 2, a fan 23 is installed in the evaporator 11, and cool air is sent by the wind of the fan 23 to perform heat exchange. The condenser 12 is connected via a heat exchange pipe (heat exchanger 16). 3 to perform heat exchange, and as shown in FIG.
2 are provided with fans 23
Can be used to perform heat exchange. Further, as shown in FIG. 4, a heat exchanger 15 is provided in the evaporator 11 and cooling water is circulated by a pump 24. A fan 23 and the like are provided on the other side of the heat exchanger 15 to blow air to generate heat. It can be configured to perform exchange.

[0011] The evaporator 11, the condenser 12, and the pipes 13 and 14 form a closed circulation line 2 for the cooling device 1.
In the present invention, in the circulation line 2, the temperature inside the evaporator 11 is set to 5 ° C. and the pressure is set to 6.5 mmHg to 30.
℃, pressure 31.8mmHg, the temperature inside the condenser 12 is 10 ℃,
At a pressure of 9.2 mmHg to 90 ° C. and a pressure of 525.8 mmHg, a cooling device for exchanging heat in the evaporator 11 and the condenser 12 is constituted. In particular, when used as an air conditioner or a cooling device, the temperature inside the evaporator 11 is set to 10 ° C. and the pressure is set to 9.2 mmH.
g to 20 ° C, pressure 17.5mmHg, indoor unit side. Then, the temperature inside the condenser 12 is set to 20 ° C. and the pressure is set to 17.5 mmHg to 60.
The cooling unit is configured to perform heat exchange with the outdoor unit side at ℃ and pressure of 149.4mmHg. Further, when actually used as a cooling device, preferably, the temperature in the evaporator 11 is 14 ° C., the pressure is 12.0 mmHg to 16 ° C., the pressure is 13.6 mmHg, and the temperature in the condenser 12 is 25 ° C., the pressure is 23.8 mmHg. ~ 35
The heat is exchanged at a temperature of 42.1mmHg at ℃.

The compressor 17 comprises a motor 20 and a fan 21. The suction side and the discharge side of the compressor 17 are not sealed. The fan 21 is, for example, an axial type or a screw type. Cross-flow fans are applied. The axial fan includes a turbo fan,
A multi-blade axial flow fan, an axial flow multi-stage fan, a fan including a moving blade and a stationary blade, and the like are included. Further, the screw type fans include those called screw type fans, single-shaft screw fans, screw groove type fans, helical type fans and the like. The fan 21 of the compressor 17 has a motor 2
The motor 20 is housed in the conduit 13 together with the fan 21 so as to prevent leakage (air intrusion) from occurring in the circulation line 2. The compressor 17 is housed in an airtight container close to a vacuum and drives the compressor 17, so that the resistance at the time of rotation of the fan 21 is small and the frictional resistance is small, so that the motor is driven at high rotation. Even if it does not burn, it does not require large horsepower and does not increase noise.

In FIG. 1, the motor 20 is accommodated in a pipe 13 on the side of the evaporator 11 so that the motor 20 can be cooled. However, as shown in FIG.
Can be arranged outside the conduit 13. At this time, the motor 20 can be covered with the cover 24 to have the same pressure as the evaporator 11 side. Similarly, as shown in FIG.
It is also possible to arrange the motor 20 outside the conduit 13 on the condenser 12 side. With this configuration, the motor 2
0 can be easily maintained, and it is possible to prevent the motor 20 from becoming difficult to flow. In addition, it is also possible to arrange the motor 20 'in the conduit 13 on the condenser 12 side as shown by the two-dot chain line in FIG.

Next, an embodiment of the present invention and the principle of heat exchange will be described with reference to FIG. An exhaust port (not shown) is provided in a part of the circulation line 2, and a vacuum pump is connected to the exhaust port to exhaust the gas. The pressure in the circulation line 2 is reduced to a substantially vacuum pressure, and water is used as a cooling medium. The inside of the evaporator 11 is filled.
Alternatively, the circulation line 2 is filled with water, the temperature is raised to 100 ° C. or more, the water is boiled, and steam and expansion components are discharged from the exhaust port. Thus, a low-pressure space close to a substantially vacuum pressure may be obtained.

However, the water serving as the cooling medium is most preferably degassed pure water.
There is no oxygen inside, no rust (oxidation) is generated, and compressors, valves and heat exchangers having metal parts are not corroded even if they are disposed in the circulation line 2, and there is no deterioration or deterioration in durability. It is. Further, since pure water has a high insulating property, it is not short-circuited by a motor or the like. Further, since pure water does not freeze until about -40 ° C, it can be used not only for air conditioners and the like but also for refrigerators and refrigerators. Further, if water is used as a simple refrigerant, a cooling cycle can be constituted even if other impurities are mixed, and the content of the impurities is preferably 30% or less in liquid or gas.

When water is charged into the evaporator 11 of the circulation line 2 having a pressure close to the vacuum, the water boils and evaporates, and the pressure in the circulation line 2 rises to the saturation pressure of the temperature at that time. For example, if the room temperature is 25 ° C., the pressure becomes 23.75 mmHg, and an equilibrium state is established. Here, when the compressor 17 is driven to lower the pressure in the evaporator 11, the water boils and evaporates more and more, and the water is cooled by the heat of vaporization (latent heat of evaporation). At this time, it takes about 595 cal / g of heat and evaporates. Then, when cooling to, for example, 5 ° C., the pressure at that time drops to 6.54 mmHg (about 0.00889 kgf / cm ² ), and boiling stops. At this time, by flowing cooling water of 5 ° C. or more through the heat exchanger 15, the cooling water is cooled and can be used for cooling or the like.

On the other hand, in the condenser 12, steam is compressed by the operation of the compressor 17, and for example, the heat exchanger 16
When water of 35 ° C. is flowed through the heat exchanger, the water vapor that has touched the heat exchanger 16 is condensed to form water droplets, and water accumulates more and more in the condenser 12. The pressure inside the condenser 12 at this time is 42.17 mmHg
(Approximately 0.05732 kgf / cm ² ), heat of condensation is also generated, and a slight rise in temperature is observed. Then, since the evaporation is performed in the evaporator 11 by the driving of the compressor 17, the water is steadily reduced. Therefore, the regulating valve 19 is appropriately opened to allow the water in the condenser 12 to flow into the evaporator 11. Be replenished. At this time, since the pressure in the evaporator 11 is lower than the pressure in the condenser 12, it is naturally sucked. At this time, a temperature rise occurs, but the specific heat of water (sensible heat) is much smaller than the latent heat, so that it is negligibly small.

In this way, water is evaporated and condensed in the circulation line 2 to complete the circulation cycle, and the evaporator 11
By arranging on the indoor side, the room can be cooled, and the condenser 12 need only be arranged outside the room.
In winter, it is also possible to heat the room by compressing in the opposite direction or exchanging the evaporator 11 and the condenser 12.

Here, the capacity required to cool the compressor 17 in the same manner as in the case of cooling with a CFC air conditioner used in ordinary households will be described with specific numerical values. Usually, the cooling capacity of an air conditioner of about 1 horsepower used in a general home is 3300 kcal / h. Assuming that the latent heat of evaporation is about 590 cal / g,
3300 (kcal / h) / 590 (kcal / kg) ≒ 5.59 (kg / h). This is 5590/60 93.2 (g / min) per minute. That is,
Approximately 100 g / min water evaporation per horsepower per minute, including losses, is required.

On the other hand, in the evaporator 11, the temperature 10
When cooled to ℃, the pressure at that time is 9.2 mmHg (0.012512
At a pressure of kgf / cm ² ), water boils to generate steam, and the volume of water vapor at this time is 106.43 l / g. Then, as described above, when evaporating 100 g per minute, the volume becomes 10643 l / min (about
11m ³ / min). On the other hand, in the condenser 12, 4
If you condense at 0 ° C, the pressure at that time is 55.32mmHg
(0.075204 kgf / cm ² ), the differential pressure between 40 ° C. and 10 ° C. is 0.062692 kgf / cm ² . The volume ratio is 106.43
l / g (10 ° C.): 19.546 l / g (40 ° C.) = 5.45: 1
It is.

That is, in the circulation line 2,
In order to obtain the same cooling capacity as a CFC air conditioner by using the latent heat of vaporization of water, the suction volume of the compressor is 11 m ³ / min.
It suffices if the pressure difference between the evaporation pressure and the condensation pressure is 0.062692 kgf / cm ² . On the other hand, this suction amount of 11 m ³ / min can be easily realized in the atmosphere because it is equivalent to a ventilating fan having a diameter of 20 cm and about 50 W. By the way, in the case of Freon R22, it is a gas at normal temperature, and a compressive force of 15.64 kgf / cm ² is required to make it liquid at 40 ° C., which requires a considerably higher pressure than the above. The latent heat of vaporization at 10 ° C. is 47 cal / g, which is very small as compared with water. However, since the volume of steam is small, the displacement of the pump can be small.

[0022]

According to the present invention having the above-described structure, the following effects can be obtained. That is, the closed circulation line 2 is formed by connecting the evaporator 11 and the condenser 12 by the pipes 13 and 14, and the compressor 17 is housed in the pipe 13, A cooling device in which a regulating valve 19 is disposed in the evaporator 11 and water is introduced into the circulation line 2 as a cooling refrigerant.
Since the heat exchange is performed in the range of mHg to 30 ° C. and the pressure of 31.8 mmHg, and the inside of the condenser 12 is set to the temperature of 10 ° C., the pressure of 9.2 mmHg to 90 ° C. and the pressure of 525.8 mmHg, the evaporator 11 Thus, a large cooling effect is obtained by the latent heat of vaporization of water, and water vapor is easily condensed and returned to water on the condenser 12 side, so that a cooling device having a simple configuration and high cooling efficiency can be obtained. Further, since the inside of the circulation line 2 is maintained at a low pressure, the driving force required for the compressor 17 is small, the driving energy is small, and the running cost is small. And since the cooling refrigerant is water, even if it leaks, it does not adversely affect the environment. Further, since the pressure inside is lower than that of a CFC-based refrigerant, there is no danger of explosion.

Further, since the suction side and the discharge side of the compressor 17 are not hermetically sealed, the pressure difference between the evaporator 11 and the condenser 12 is instantaneously eliminated when the cooling device is stopped, and There is no need to provide a seal or a valve mechanism for separating the quantity space in the machine, and the structure of the compressor can be simplified.

Further, since the compressor 17 is constituted by an axial flow type fan or a screw type fan, a large capacity can be continuously sucked and exhausted.

[Brief description of the drawings]

FIG. 1 is a diagram showing a cooling device of the present invention.

FIG. 2 is a view showing an embodiment in which the evaporator performs heat exchange with a fan in the cooling device of the present invention.

FIG. 3 is a view showing an embodiment in which heat is exchanged between an evaporator and a condenser by a fan in the cooling device of the present invention.

FIG. 4 is a view showing an embodiment in which a heat exchanger of an evaporator is a pipe type in the cooling device of the present invention, and heat is exchanged by a fan on the other side.

FIG. 5 is a view showing an embodiment in which the motor of the compressor is disposed outside the pipe on the evaporator side in the cooling device of the present invention.

FIG. 6 is a view showing an embodiment in which a compressor motor is disposed outside a conduit on a condenser side in the cooling device of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cooling apparatus 2 Circulation line 11 Evaporator 12 Condenser 13.14 Pipeline 15.16 Heat exchanger 17 Compressor 19 Control valve

Claims (4)

[Claims] A line (1) is provided between an evaporator (11) and a condenser (12).
3 and a conduit 14 to form a closed circulation line 2, and a compressor 17 is housed in the conduit 13,
This is a cooling device in which a regulating valve 19 is disposed in the pipe 14 and water is introduced into the circulation line 2 as a cooling refrigerant.
31.8mmHg range, the temperature inside the condenser 12 is 10 ° C,
A cooling device characterized in that heat exchange is performed within a range of a pressure of 9.2 mmHg to a temperature of 90 ° C. and a pressure of 525.8 mmHg. 2. The cooling device according to claim 1, wherein a portion between the suction side and the discharge side of the compressor is not sealed. 3. The cooling device according to claim 1, wherein said compressor is constituted by an axial fan. 4. The cooling device according to claim 1, wherein said compressor 17 is constituted by a screw fan.