JP2001235290A - Freezing cycle apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the difficult with a prior art secondary cold refrigerant freezing cycle apparatus that it consumes inceasingly energy so that it is unlikely to contribute to global warming prevention. SOLUTION: A compressor 1, a heat source side heat exchanger 3, and a throttle apparatus 4 are connected with each other at least through piping, and a heat source side cycle 7 in which a heat medium A is encapsulated, a load side heat exchanger 8, and a pump 9 are connected with each other at least through piping. Further, a load side cycle 10 in which a heat medium B is encapsulated, and a direct heat exchanger 6 into which the heat medium A and the heat medium B flow and which brings them into a contact with each other for direct heat exchange are provided. The heat medium A is forced to circulate the heat source side cycle 7 via the direct heat exchanger 6 while the heat medium B is forced to circulate the load side cycle 10 via the direct heat exchanger 6, whereby a difference of parameters of solubilities of the heat medium A and the heat medium B set to be 2. 10 (cal/cm3)0.5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigeration cycle apparatus, and more particularly, to a secondary refrigerant refrigeration cycle apparatus in which different heat media are circulated between a heat source cycle and a load cycle.

[0002]

2. Description of the Related Art Conventionally, a secondary refrigerant refrigeration cycle apparatus as shown in FIG. 3 has been used as a secondary refrigerant refrigeration cycle apparatus in which different heat mediums circulate between a heat source side cycle and a load side cycle.

In FIG. 3, a compressor 21, a four-way valve 22,
The heat-source-side heat exchanger 23, the expansion device 24, and the heat-source-side intermediate heat exchanger 25 are connected by pipes, and a HCFC 22 as a heat medium is generally enclosed therein to form a heat-source-side cycle 26. Further, the load-side intermediate heat exchanger 27, the load-side heat exchanger 28, and the pump 29 as a conveying means are connected by pipes, and water is generally enclosed therein as a heat medium to constitute a load-side cycle 30. I have.

[0004] Here, the heat source side intermediate heat exchanger 25 and the load side intermediate heat exchanger 27 are integrally formed, and HCF which is a heat medium of the heat source side cycle 26 is passed through a heat transfer surface such as a metal wall.
C22 and water as a heat medium of the load side cycle 30 indirectly exchange heat (heat exchange without direct contact between the HCFC 22 and water), and use the heat source side heat exchanger 23 to obtain cold or warm heat obtained from outside. It is used for cooling or heating in the load side heat exchanger 28 via the side intermediate heat exchanger 25 and the load side intermediate heat exchanger 27. The refrigeration cycle device described with reference to FIG. 3 is a known secondary refrigerant refrigeration cycle device.

[0005] There is a growing interest in protecting the global environment, and from the viewpoint of protection of the ozone layer, HCFCs including HCFC22 are being converted to HFCs that do not destroy the ozone layer. There is a need for improved energy savings.

[0006]

However, the conventional secondary refrigerant refrigeration cycle apparatus includes a step of indirectly exchanging heat between the heat medium of the heat source cycle 26 and the heat medium of the load cycle 30. For this reason, a temperature difference is always required between the heat medium of the heat source side cycle 26 and the heat medium of the load side cycle 30, and the condensing temperature in the heat source side intermediate heat exchanger 25 is increased (that is, the discharge pressure of the compressor 21 is reduced). Rise) or decrease the evaporation temperature in the heat source side intermediate heat exchanger 25 (compressor 2
(1) the suction pressure must be reduced). On the heat source side cycle 26 side, when cold or warm heat is obtained from the outside, the compression ratio of the compressor 21 becomes larger than in the direct expansion system, and the energy consumption increases. Therefore, the conventional 2
Secondary refrigerant refrigeration cycle devices have been difficult to contribute to the prevention of global warming.

An object of the present invention is to provide a refrigeration cycle apparatus which can improve energy saving and contribute to the prevention of global warming in consideration of the above-mentioned problems.

[0008]

Means for Solving the Problems The first invention (claim 1)
Corresponding to the present invention described in), a compressor, a heat source side heat exchanger,
A heat source side cycle in which the expansion device is connected to at least a pipe and the heat medium A is sealed therein, and a load side heat exchanger and a transfer means are at least connected to a pipe, and the heat medium B is sealed therein. A load-side cycle, and a direct heat exchanger that causes the heat medium A and the heat medium B to flow thereinto, and causes the heat medium A and the heat medium B to contact each other to perform direct heat exchange, The heat medium A circulates through the heat source side cycle via the direct heat exchanger, the heat medium B circulates through the load side cycle via the direct heat exchanger, and the heat medium A and the heat medium A refrigeration cycle apparatus characterized in that a difference in solubility parameter of the medium B is equal to or more than a predetermined value.

According to a second aspect of the present invention (corresponding to the second aspect of the present invention), the predetermined value is 2.10 (cal / cm ³ ) ^0.5
The refrigeration cycle apparatus according to the first aspect of the present invention,

According to a third aspect of the present invention (corresponding to the third aspect of the present invention), all or a part of the compressor, the expansion device, and the transfer means are provided on the heat source side in the direct heat exchanger. Cycle and the load side cycle,
The refrigeration cycle apparatus according to the first or second aspect of the present invention, wherein the heat medium A and the heat medium B are controlled so as not to substantially mix.

According to a fourth aspect of the present invention (corresponding to the fourth aspect of the present invention), all or a part of the compressor, the expansion device, and the conveying means are provided on the heat source side of the direct heat exchanger. The refrigeration cycle apparatus according to the first or second aspect of the present invention, wherein the degree of superheating or the degree of supercooling of the heat medium A at the cycle outlet is controlled to be equal to or greater than a predetermined value x.

According to a fifth aspect of the present invention (corresponding to the fifth aspect of the present invention), all or a part of the compressor, the expansion device, and the conveying means are provided on the heat source side of the direct heat exchanger. The refrigeration cycle apparatus according to the first or second aspect of the present invention, wherein the degree of superheating or the degree of supercooling of the heat medium A at a cycle outlet is controlled to be equal to or less than a predetermined value y.

In the refrigeration cycle apparatus according to any one of the first to fifth aspects of the present invention, the density of the heat medium A is preferably smaller than the density of the heat medium B in the direct heat exchanger. .

In the refrigeration cycle apparatus according to any one of the first to fifth aspects of the present invention, the heat medium A flows into the direct heat exchanger from above the direct heat exchanger, and the heat medium A Preferably, B flows into the direct heat exchanger from below the direct heat exchanger.

Further, in the refrigeration cycle apparatus according to any one of the first to fifth aspects of the present invention, the heat source-side cycle may include the heat medium A flowing from the direct heat exchanger to the heat source-side heat exchanger. And an auxiliary heat exchanger for indirectly exchanging heat with the heat medium A flowing from the heat source side heat exchanger to the direct heat exchanger.

In the refrigeration cycle apparatus according to any one of the first to fifth aspects of the present invention, the heat medium B may be a non-aqueous medium, in which case the heat source side cycle and / or Alternatively, it is preferable that the load side cycle includes a dryer that collects moisture.

Further, in the refrigeration cycle apparatus according to any one of the first to fifth aspects of the present invention, all or a part of the compressor, the expansion device, and the transporting means are provided with the heat medium A. It is preferable that the evaporation temperature in the direct heat exchanger is controlled to be equal to or higher than the melting point of the heat medium B.

In the refrigeration cycle apparatus according to any one of the first to fifth aspects of the present invention, the heat medium B is water or a mixture containing water as a main component, and the compressor and the expansion device And that all or a part of the conveying means is controlled so that the evaporation temperature of the heat medium A in the direct heat exchanger is equal to or higher than the clathrate critical decomposition point temperature with the heat medium B. preferable.

In the refrigeration cycle apparatus according to any one of the first to fifth aspects of the present invention, the heat medium A may be a hydrocarbon having 3 or less carbon atoms, isobutane, HFC3.
2. HFC125, HFC134a, or carbon dioxide, or a medium containing at least a part thereof, wherein the heat medium B is water, γ-butyrolactone, propylene carbonate, or a medium containing at least a part thereof. Is preferred.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

(Embodiment 1) FIG. 1 is a configuration diagram of a refrigeration cycle apparatus according to Embodiment 1 of the present invention.

In FIG. 1, 1 is a compressor, 2 is a first four-way valve, 3 is a heat source side heat exchanger, 4 is a throttling device, 5 is a second four-way valve, and 6 is a direct heat exchanger. Heat medium A, which is a substance connected to piping and does not destroy the ozone layer inside
Are enclosed to constitute the heat source side cycle 7. Also,
8 is a load side heat exchanger, 9 is a pump as a conveying means, and these and a direct heat exchanger 6 acting as an intermediate heat exchanger are connected by piping, and a heat medium B is sealed inside,
The load-side cycle 10 is configured.

Here, the Fedors solubility parameter (Polyme
r Engineering and Science, February, 1974, vol. 14,
No. 2) is used for qualitatively estimating the solubility from the chemical structure of a substance. Generally speaking, if the solubility parameters of multiple substances to be mixed are the same, it is easy to dissolve each other. Have been done. Therefore, prior to selection of the heat medium A and the heat medium B to be enclosed in the refrigeration cycle apparatus shown in FIG. 1, the heat medium A and the heat medium B are injected into a glass container,
A compatibility experiment was performed. Table 1 shows solubility parameters at 25 ° C. (values in parentheses in Table 1 are expressed in units of (cal / cm
³ ) ^0.5 , and the solubility parameter of water is not described in the above literature, but it is said to be 10 or more).

[0024]

[Table 1] According to Table 1, the solubility parameter difference between the heat medium A and the heat medium B is about 2.10 and the solubility parameter difference is about 2.10.
When it is larger than 10, it has been found that even if the heat medium A and the heat medium B are mixed, there is a high possibility that they are separated without being dissolved.

In the following description of the first embodiment, as an example, the heat medium A will be described as propane and the heat medium B as water.

The density of propane is 0.500 g / cm ³ (saturated liquid density) and the density of water is 0.998 g / cm ³ at 20 ° C., for example. Is also small.

The direct heat exchanger 6 of the heat source side cycle 7
A superheat / supercool detector 11 is provided on the outlet side.

The operation of such a refrigeration cycle apparatus will be described for the case where cooling is performed by the load-side heat exchanger 8.

When cooling with the load side heat exchanger 8, the first
The four-way valve 2 and the second four-way valve 5 are set as shown by the broken lines in FIG. 1, and the heat medium A and the heat medium B are circulated as shown by the broken arrows in the figure. The heat medium A, which has been compressed by the compressor 1 to have a high temperature and a high pressure, is radiated to the outside through the first heat exchanger 3 acting as a condenser via the first four-way valve 2 to be condensed and liquefied. The pressure is reduced to a low-temperature low-pressure gas-liquid two-phase state, and is introduced directly into the heat exchanger 6 via the second four-way valve 5.

At this time, the direct heat exchanger 6 acts as an evaporator for the heat source side cycle 7, and by cooling the heat medium B, the heat medium A evaporates to a gaseous state. It flows out from the inner upper part, is sucked into the compressor 1 through the second four-way valve 5 and the first four-way valve 2, and is compressed again. Further, the heat medium B cooled by the heat medium A in the direct heat exchanger 6 flows out from the lower part of the heat exchanger 6 directly, cools the load in the load side heat exchanger 8, and then passes through the pump 9 again. It is sent directly to the heat exchanger 6.

In the direct heat exchanger 6, the heat medium A and the heat medium B
Are mixed and directly in contact with each other to perform heat exchange, thereby performing heat exchange more efficiently than heat exchange through a conventional heat transfer surface such as a metal wall, and thereafter, heat medium A and heat medium B Are rapidly separated because the difference in their solubility parameters is as low as 2.10 or more, so that the heat medium A is continuously circulated to the heat source cycle 7 and the heat medium B is continuously circulated to the load cycle 10. It is possible to do.

Therefore, in the conventional secondary refrigerant refrigeration cycle apparatus, since the step of indirectly exchanging heat between the heat medium of the heat source cycle and the heat medium of the load side cycle is not included, the heat medium of the heat source cycle 7 is not included. A and load side cycle 10
The temperature difference between the heat medium B and the heat medium B can be made extremely small, and the increase in the compression ratio of the compressor 1 is suppressed on the heat source side cycle 7 side that generates cold heat as compared with the direct expansion system, so that energy saving is improved. .

Further, by making the density of the heat medium A smaller than the density of the heat medium B, the heat medium A is directly discharged from the upper part in the heat exchanger 6 and the heat medium B is discharged from the lower part, thereby mixing the heat medium A. The separation after the direct contact heat exchange is further promoted, and the heat medium A is mixed in the load side cycle 10 even when the heat medium A is accumulated in the liquid state without being completely evaporated in the direct heat exchanger 6. Can be prevented, and an increase in energy consumption due to the shortage of the heat medium A in the heat source side cycle 7 can be avoided.

The superheat / supercool detector 11 is provided at the outlet of the direct heat exchanger 6 of the heat source cycle 7 because the direct heat exchanger 6 acts as an evaporator for the heat source cycle 7. The superheat degree of the heat medium A in the section is detected. Then, the compressor 1 is controlled so that the detected degree of superheat is equal to or more than the predetermined value x1.
The amount of compression of the heat medium A (the number of revolutions and the piston stroke is excluded volume, etc.), the amount of decompression of the expansion device 4 (switching of capillaries having different lengths or inner diameters, opening degree in the case of an expansion valve, etc.),
The amount of heat medium B transported by the pump 9 (the number of revolutions, the piston stroke, the excluded volume, etc.) is operated.

Therefore, the heat medium A is surely evaporated to be in a gaseous state and the density is further reduced.
Is further promoted, the heat medium A can be circulated with high purity in the heat source side cycle 7, the operation can be efficiently performed without being affected by the heat medium B, and the energy saving property is improved.

Since the degree of superheat = the temperature of the heat medium A-the saturation temperature with respect to the pressure at that time, if the predetermined value x1 of the degree of superheat is 0 ° C. or more, the heat medium A is completely evaporated. It becomes a gas state, and is about 1/50 or less of the saturated liquid density (for example, in the case of propane, 10 ° C. saturated liquid density = 0.515 g)
/ Cm ³ , saturated gas density at 10 ° C = 0.01036 g / c
m ³ ), and the density difference between the heat medium B and the heat medium B
However, the predetermined value x1 may be set to, for example, about 1 to 5 ° C. in consideration of an error in the measurement of the degree of superheat.

On the other hand, when the degree of superheating of the heat medium A increases,
The vapor pressure of the heat medium B with respect to the saturation pressure of the heat medium A is relatively increased as compared with the case where the superheat degree is small, and therefore, the heat medium A included in the heat medium A at the outlet of the direct heat exchanger 6 of the heat source side cycle 7 is included. Heat medium B increases, and the heat source side cycle 7
Then, the heat medium B circulates together with the heat medium A,
Under the influence of the heat medium B, there is a possibility that the efficiency of the heat source side cycle 7 is reduced, or the reliability of the compressor 1 is deteriorated.

For example, when the heating medium A is propane and the heating medium B is water, the saturated water content in propane when the evaporation temperature of propane is 10 ° C. is about 3600 when the superheat degree is 10 ° C.
ppm, the superheat degree is about 6600 ppm when the superheat degree is 20 ° C., and the higher the superheat degree, the higher the saturated water content. However, the predetermined value y1 of the degree of superheat is changed to the reliability (such as the allowable moisture content) of the components such as the compressor 1 constituting the heat source side cycle 7.
The superheat degree of the heat medium A at the outlet of the direct heat exchanger 6 of the heat source side cycle 7 detected by the superheat degree / supercool degree detector 11 is set to a predetermined value y1 or less. By operating the compression amount of the heat medium A of the compressor 1, the pressure reduction amount of the expansion device 4, and the conveyance amount of the heat medium B of the pump 9, the heat medium side cycle 7 can circulate the heat medium A with high purity. It can be operated efficiently without being affected by the heat medium B, and the reliability is improved. Further, by setting the predetermined value x1 to be smaller than the predetermined value y1, the degree of superheat can be maintained in an appropriate range.

Next, a case where heating is performed in the load side heat exchanger 8 will be described.

When heating is performed by the load-side heat exchanger 8, the first
If the four-way valve 2 and the second four-way valve 5 are set as shown by the solid line in FIG. 1 and the heat medium A and the heat medium B are circulated as shown by the solid arrows in the figure, the heat source side heat exchanger 3 evaporates. The direct heat exchanger 6 acts as a condenser with respect to the heat source side cycle 7, and forms a heat medium A of the heat source side cycle 7 and a heat medium B of the load side cycle 10 similarly to the cooling. The temperature difference between the compressors can be made extremely small, and an increase in the compression ratio of the compressor is suppressed on the heat source side cycle 7 side that generates heat, as compared with the direct expansion system, so that energy saving is improved.

The superheat degree / supercool degree detector 11 is provided at the outlet of the direct heat exchanger 6 of the heat source side cycle 7 because the direct heat exchanger 6 acts as a condenser for the heat source side cycle 7. The degree of supercooling of the heat medium A in the section is detected. In the direct heat exchanger 6, the heat medium A is brought into a liquid state by directly contacting the heat medium B and heating the heat medium B.
When the heat medium A in a gaseous state that cannot be completely condensed (the density is even smaller than the heat medium A in a liquid state) is present, the heat medium A in the gaseous state becomes a heat medium B, an interface between the heat medium A and the heat medium B. When moving upward through the heat medium A in a liquid state, the interface between the heat medium A and the heat medium B is disturbed (that is, the heat medium A and the heat medium B are stirred to prevent separation).

However, the amount of compression of the heat medium A of the compressor 1, the amount of decompression of the expansion device 4, the amount of decompression, The heat medium B transport amount of the pump 9 is operated. Accordingly, the heat medium A can be surely condensed without the presence of the heat medium A in a gaseous state that cannot be completely condensed, becomes a liquid state having a density lower than that of the heat medium B, and can be separated above the heat medium B. .
Therefore, in the heat source side cycle 7, the heat medium A can be circulated with high purity and can be operated efficiently without being affected by the heat medium B,
Energy saving is improved.

Since the degree of supercooling = the saturation temperature with respect to the pressure at that time−the temperature of the heat medium A, the heat medium A is completely condensed if the predetermined value x2 of the degree of supercooling is 0 ° C. or more. Then, the predetermined value x2 may be set to, for example, about 1 to 5 ° C. in consideration of an error in the measurement of the degree of superheat and the like.

On the other hand, when the degree of supercooling, which is the difference between the saturated condensation temperature of the heat medium A and the temperature in the liquid state, increases, the temperature of the heat medium A in the liquid state decreases. Since the density of the liquid increases as the temperature decreases, the density difference between the heat medium A and the heat medium B in the liquid state decreases, and the separation of the heat medium A and the heat medium B becomes insufficient. The heat medium B contained in the heat medium A at the outlet of the direct heat exchanger 6 increases, and in the heat source side cycle 7, the heat medium B circulates together with the heat medium A, and the heat medium B is affected by the heat medium B. There is a possibility of causing a problem in reliability due to a decrease in efficiency of the side cycle 7 and a deterioration of the compressor 1.

For example, the heat medium A is propane and the heat medium B is
In the case of water, propane when the condensation temperature of propane is 50 ° C
The liquid density of 0.468 g /
cm ^Three0.487 g / cm if the degree of supercooling is 20 ° C.^Three
And the liquid density increases as the degree of supercooling increases.
However, the predetermined value y2 of the degree of supercooling is directly changed to the state of the heat exchanger 6.
(Circulation speed range of heat medium A or heat medium B or direct heat exchanger 6
Of the heat medium A and heat medium B due to the density difference
Superheat / supercool detector, set in consideration of degree
Direct heat exchanger 6 of heat source side cycle 7 detected at 11
The degree of supercooling of the heat medium A at the mouth becomes equal to or less than a predetermined value y2.
The amount of compression of the heat medium A of the compressor 1 and the pressure reduction of the expansion device 4
By controlling the amount and the amount of heat medium B transported by the pump 9,
In the heat source side cycle 7, the heat medium A is circulated with high purity.
And efficient operation without being affected by heat medium B
And reliability is improved. Also, a predetermined value x2 is set to a predetermined value.
By setting smaller than the value y2, the degree of superheat
It is possible to keep it in a proper range.

When the compression amount of the heat medium A of the compressor 1, the pressure reduction amount of the expansion device 4, and the conveyance amount of the heat medium B of the pump 9 are controlled, the circulation speed of the heat medium A and the heat medium B changes. Therefore, by performing the above-described control and adjusting the circulation speed of the heat medium A and the heat medium B to an appropriate value, the heat exchange rate in the direct heat exchanger 6 can be increased, and the direct heat exchanger 6 The heat medium A and the heat medium B can be separated from each other.

Further, depending on the size of the direct heat exchanger 6 and the length of the direct heat exchanger 6 in the cycle direction of the heat medium A and the heat medium B, the circulation speed of the heat medium A and the heat medium B is appropriate. It is necessary to control all or a part of the compressor 1, the expansion device 4, and the pump 9 so that the values are obtained.

(Embodiment 2) FIG. 2 is a configuration diagram of a refrigeration cycle apparatus according to Embodiment 2 of the present invention.

In FIG. 2, the same components as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted. 12 is an auxiliary heat exchanger for indirectly exchanging heat between the heat medium A exiting the heat exchanger acting as a condenser and the heat medium A exiting the heat exchanger acting as an evaporator, and 13 is a first throttle. Device, 14 second
It is an aperture device. Further, the heat medium B of the load side cycle 10
A dryer 15 that collects moisture in the load side cycle 10 or the heat source side cycle 7 when a medium other than an aqueous system (water or a mixture containing water as a main component), for example, γ-butyrolactone is used. Further, an evaporation temperature detector 16 for directly detecting the evaporation temperature of the heat medium A in the heat exchanger 6 is provided.

When cooling is performed by the load side heat exchanger 8, the first
The pressure reduction amount in the expansion device 13 is set to be small, and the pressure reduction amount in the second expansion device 14 is set to be large, and the first four-way valve 2 and the second four-way valve 5 are set.
Is set as shown by the broken line in FIG. 2, and the heat medium A and the heat medium B are circulated as shown by the broken arrows in the figure. The heat medium A, which has been compressed by the compressor 1 to have a high temperature and a high pressure, passes through the first four-way valve 2 and is radiated to the outside by the heat source side heat exchanger 3 acting as a condenser to condense and liquefy. At 13, the pressure is hardly reduced, and the pressure is reduced by the second expansion device 14 through the auxiliary heat exchanger 12 to be in a low-temperature low-pressure gas-liquid two-phase state, and is introduced directly into the heat exchanger 6 through the second four-way valve 5. .

At this time, the direct heat exchanger 6 acts as an evaporator for the heat source side cycle 7, and by cooling the heat medium B, the heat medium A evaporates to a gaseous state. It flows out from the inner upper part, is sucked into the compressor 1 through the second four-way valve 5, the first four-way valve 2, and the auxiliary heat exchanger 12, and is compressed again. The heat medium B cooled by the heat medium A in the direct heat exchanger 6 flows out from the lower part of the direct heat exchanger 6 and cools the load in the load side heat exchanger 8, and then the pump 9
Again to the heat exchanger 6 directly.

In the direct heat exchanger 6, as described in the first embodiment, the heat medium A and the heat medium B are mixed and directly in contact with each other to perform heat exchange. The superheat degree at the outlet of No. 6 is detected by the superheat / subcool degree detector 11, and the compressor 1, the first expansion device 13, the second expansion device 14, and the pump 9 are controlled so that the superheat is within a predetermined range. Manipulate.

Further, the auxiliary heat exchanger 12 uses the second expansion device 1
Indirect heat exchange between the heat medium A introduced into the compressor 4 and the heat medium A drawn into the compressor 1 causes the second expansion device 1
4, the degree of supercooling of the heat medium A introduced into the heat medium 4 is increased, and the enthalpy at the inlet of the direct heat exchanger 6 acting as an evaporator of the heat source side cycle 7 is reduced, so that the heat exchange with the heat medium B And the cooling capacity of the load-side heat exchanger 8 can be increased without increasing the energy consumption of the compressor 1.

Further, in order to more reliably separate the heat medium A and the heat medium B in the direct heat exchanger 6, the superheat degree detected by the superheat / subcool degree detector 11 is set to a predetermined value y1 or less. If the auxiliary heat exchanger 12 is not provided due to a sudden change in load or a sudden change in the heat source side environmental condition,
Although there is a possibility that the non-evaporated heat medium A may be transiently drawn into the compressor 1, the provision of the auxiliary heat exchanger 12 indirectly causes the high-temperature heat medium A introduced into the second expansion device 14. Since the heat is exchanged between the compressor 1 and the compressor 1, the evaporation can be surely performed, and the compressor 1 can be prevented from being damaged.

Next, when heating is performed in the load side heat exchanger 8, the pressure reduction amount in the first expansion device 13 is set to be large, and the pressure reduction amount in the second expansion device 14 is set to be small. Second
If the four-way valve 5 is set as shown by the solid line in FIG. 2 and the heat medium A and the heat medium B are circulated as shown by the solid arrows in the figure, the heat source side heat exchanger 3 acts as an evaporator, The heat exchanger 6 acts as a condenser for the heat source side cycle 7. Further, in the auxiliary heat exchanger 12, the heat medium A introduced into the first expansion device 13 while being hardly depressurized by the second expansion device 14;
The heat medium A sucked into the compressor 1 indirectly exchanges heat.

In the direct heat exchanger 6, as described in the first embodiment, the heat medium A and the heat medium B are mixed and directly in contact with each other to perform heat exchange. The supercooling / supercooling degree detector 11 detects the degree of supercooling at the outlet of No. 6
, The compressor 1, the first expansion device 13, the second expansion device 14, and the pump 9 are operated so that the degree of supercooling falls within a predetermined range.

Further, the auxiliary heat exchanger 12 controls the first expansion device 1
The heat medium A introduced into the compressor 3 and the heat medium A sucked into the compressor 1 are indirectly heat-exchanged to form a direct heat exchanger 6.
In order to more surely separate the heat medium A and the heat medium B in the first throttle device, the supercooling degree detected by the superheat / supercooling degree detector 11 is maintained at a predetermined value y2 or less. 13, the degree of supercooling of the heat medium A introduced into the heat source 13 increases, the enthalpy at the inlet of the heat source side heat exchanger 3 acting as an evaporator decreases, the amount of heat exchange with the heat source increases, and 1, the amount of heat exchange with the heat medium B in the direct heat exchanger 6 and the heating capacity in the load side heat exchanger 8 can be increased without increasing the consumed energy.

A medium other than an aqueous medium (water or a mixture containing water as a main component) is used as the heat medium B of the load-side cycle 10 whose solubility parameter difference with the heat medium A of the heat source-side cycle 7 is 2.10 or more. For example, when γ-butyrolactone is used, since the solubility parameter is close to the solubility parameter of water, the heat medium B and water have high compatibility, that is, the heat medium B has strong water absorption. Therefore, when the refrigeration cycle apparatus is installed, relocated, or maintained, the heat medium B absorbs the surrounding moisture and mixes the moisture into the load side cycle 10 and the heat source side cycle 7, thereby improving the reliability of the refrigeration cycle apparatus. There is a problem that impairs.

However, as shown in FIG. 2, the load side cycle 10 is provided with a dryer 15 for collecting moisture, or the heat source side cycle 7 is provided with a dryer for collecting moisture (not shown). Moisture mixed in the cycle 10 or the heat source side cycle 7 is quickly removed from the dryer 1.
5, the reliability of the refrigeration cycle apparatus can be prevented from being impaired.

Further, the compressor 1 and the expansion device (FIG. 1) are so arranged that the evaporation temperature of the heat medium A in the direct heat exchanger 6 detected by the evaporation temperature detector 16 is higher than the melting point of the heat medium B. 4 or the first aperture device 13 or the second aperture device 1 in FIG.
4) By operating the pump 9 and the direct heat exchanger 6
It is possible to solve the problem that the heat medium B is solidified in the inside and the circulation of the heat medium A is prevented, or the small pieces of the solidified heat medium B are combined in the load side cycle 10 and the circulation of the heat medium B is prevented.

Further, the heat medium B is water or a mixture containing water as a main component, and the heat medium A is a substance forming a clathrate with water (for example, a hydrocarbon or isobutane having 3 or less carbon atoms, or HFC32 or HFC125). , HFC13
4a, carbon dioxide, or at least one of these
In the case of a mixture containing a substance, the evaporation temperature of the heat medium A in the direct heat exchanger 6 detected by the evaporation temperature detector 16 is set to be equal to or higher than the clathrate critical decomposition temperature with water. , The compressor 1 and the throttle device (4 in FIG. 1 or FIG.
The first throttle device 13 and the second throttle device 14) and the pump 9 in the inside
Is operated, the water as the heat medium A and the heat medium B directly generates the clathrate in the heat exchanger 6 to prevent the circulation of the heat medium A, or a small piece of the generated clathrate is used as the load side cycle. It is possible to solve the problem that the circulation of the heat medium B is hindered due to the connection inside the heat medium 10.

In the second embodiment, the first expansion device 13 and the second expansion device 14 are arranged before and after the auxiliary heat exchanger 12. However, the present invention is not limited to this. For example, a configuration in which one expansion device is arranged downstream of the auxiliary heat exchanger 12 may be used.

The evaporating temperature detector 16 detects the evaporating saturation temperature of the heat medium A directly based on the temperature in the heat exchanger 6 or a throttling device (4, 13 or 1).
The evaporating temperature of the heat medium A may be detected based on the temperature of the heat medium A decompressed in 4) or directly based on the saturation temperature obtained from the pressure near the heat exchanger 6.

In Embodiments 1 and 2, propane is used as the heat medium A, and water or γ-butyrolactone is used as the heat medium B. However, the present invention is not limited to this. HFC32 (solubility parameter 7.17, density 0.981 g / cm ³ ), propylene carbonate (solubility parameter 9.3)
5, the density, 1.206 g / cm ³ ), the above-described operation, action, and effect can be obtained (the difference in the solubility parameter in this case is 2.18). In short, the difference in the solubility parameter between the heat medium A and the heat medium B is small. If it is 2.10 or more, the compatibility is low,
Separation can be performed directly in the heat exchanger 6 and the heat source side cycle 7
In this case, a refrigeration cycle apparatus that can circulate the heat medium A and circulate the heat medium B through the load side cycle 10 to improve energy saving and contribute to prevention of global warming can be provided.

The refrigeration cycle apparatus is used for:
It is not limited to air conditioning, freezing, refrigeration, hot water supply, and the like.
Further, the present invention can also be applied to a refrigeration cycle device that performs both the cooling and heating functions or one of the functions. When the present invention is applied to a refrigeration cycle apparatus that performs both functions of cooling and heating, the flow direction of the heat medium may be switched using an on-off valve or a check valve instead of the second four-way valve. In addition, when the present invention is applied to a refrigeration cycle that performs either cooling or heating, a four-way valve is unnecessary.

As described above, the heat medium A circulating in the heat source cycle 7 and the heat medium B circulating in the load cycle 10 are brought into direct contact with each other to provide the direct heat exchanger 6 for heat exchange. 1. The solubility parameter difference between the medium A and the heat medium B
When the ratio is 10 or more, the heat medium A and the heat medium B have low compatibility. Therefore, the heat medium A and the heat medium B are separated immediately after the direct contact heat exchange. The medium B can be continuously circulated. Therefore, since a step of indirectly exchanging heat between the heat medium of the heat source side cycle and the heat medium of the load side cycle as in the conventional secondary refrigerant refrigeration cycle apparatus is not included, the direct expansion system on the heat source side cycle side is not included. The increase in the compression ratio of the compressor is suppressed as compared with the above, and the energy saving is improved.

The heat source side cycle 7 of the direct heat exchanger 6
By setting the degree of superheating of the heat medium A at the outlet to a predetermined value x1 or more, the heat medium A is surely evaporated to be in a gaseous state and the density is further reduced, so that separation from the heat medium B is further promoted. Thus, in the heat source side cycle 7, the heat medium A can be circulated with high purity, the operation can be efficiently performed without being affected by the heat medium B, and the energy saving property is improved. Alternatively, the heat medium A at the outlet of the heat source side cycle 7 of the direct heat exchanger 6
By setting the degree of supercooling to be equal to or more than the predetermined value x2, the heat medium A is surely condensed without the presence of the heat medium A in a gaseous state that cannot be completely condensed, and becomes a liquid state having a smaller density than the heat medium B. The heat source side cycle 7 can be operated efficiently without being affected by the heat medium B, and the energy saving property is improved.

The heat source side cycle 7 of the direct heat exchanger 6
By setting the degree of superheating of the heat medium A at the outlet to a predetermined value y1 or less, the heat medium A can be circulated with high purity in the heat source side cycle 7, and the operation can be efficiently performed without being affected by the heat medium B. Energy efficiency is improved. Alternatively, by setting the degree of supercooling of the heat medium A at the outlet of the heat source side cycle 7 of the direct heat exchanger 6 to a predetermined value y2 or less, the heat medium A can be circulated with high purity in the heat source side cycle 7. In addition, efficient operation can be performed without being affected by the heat medium B, energy savings can be improved, and the reliability of components such as the compressor 1 can be improved.

Further, by making the density of the heat medium A smaller than that of the heat medium B, separation after direct contact heat exchange by mixing is promoted.

Also, the heat medium A
And the heat medium B is discharged from the lower part of the direct heat exchanger 6 to further promote the separation after the direct contact heat exchange by mixing, and the heat medium A evaporates in the direct heat exchanger 6. Even if it accumulates in the liquid state without being
It is possible to prevent the heat medium A from being mixed into the load side cycle 10 and to avoid an increase in energy consumption due to the shortage of the heat medium A in the heat source side cycle 7.

Further, by providing an auxiliary heat exchanger 12 for indirectly exchanging heat between the outlet of the evaporator and the suction part of the compressor and between the outlet of the condenser and the inlet of the expansion device, the device functions as an evaporator. The enthalpy at the inlet of the heat exchanger is reduced, and without increasing the energy consumption of the compressor 1,
The cooling capacity or the heating capacity of the load side heat exchanger 8 can be increased. Furthermore, there is a possibility that the unevaporated heat medium A may be transiently sucked into the compressor 1,
Since the heat is indirectly exchanged with the high-temperature heat medium A introduced into the expansion device by the auxiliary heat exchanger 12, the vapor is reliably evaporated and the compressor 1 can be prevented from being damaged.

When the heating medium B is a non-aqueous system, a dryer for collecting moisture is provided in the heat source side cycle 7 or the load side cycle 10 so that the load side cycle 1 can be reduced.
Moisture mixed in the heat source 0 and the heat source side cycle 7 is quickly collected by the dryer, so that the reliability of the refrigeration cycle apparatus can be prevented from being impaired.

Further, by setting the evaporation temperature of the heat medium A in the direct heat exchanger 6 to be higher than the melting point of the heat medium B, the heat medium B solidifies in the direct heat exchanger 6 and the heat medium A is circulated. Of the heat medium B that has been hindered or solidified
It is possible to solve the problem that the heat medium B is prevented from being circulated by being connected within 0.

Further, the heat medium B is water or a mixture containing water as a main component, and the evaporation temperature of the heat medium A in the direct heat exchanger 6 is equal to or higher than the clathrate critical decomposition point temperature with the heat medium B. As a result, a clathrate is generated and heat medium A
Of the heat medium B is prevented from being circulated or the generated small pieces of the clathrate are combined in the load side cycle 10 to prevent the circulation of the heat medium B.

[0075]

As is apparent from the above description, the present invention can provide a refrigeration cycle apparatus that can improve energy saving and contribute to prevention of global warming.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a refrigeration cycle apparatus according to Embodiment 1 of the present invention.

FIG. 2 is a configuration diagram of a refrigeration cycle apparatus according to Embodiment 2 of the present invention.

FIG. 3 is a configuration diagram of a conventional refrigeration cycle device.

[Explanation of symbols]

 1: Compressor 2: First four-way valve 3: Heat source side heat exchanger 4: Throttle device 5: Second four-way valve 6: Direct heat exchanger 7: Heat source side cycle 8: Load side heat exchanger 9: Pump 10: Load side cycle 11: Superheat / supercool detector 12: Auxiliary heat exchanger 13: First expansion device 14: Second expansion device 15: Dryer 16: Evaporation temperature detector 21: Compressor 22: Four-way valve 23: Heat source side heat exchanger 24: Throttle device 25: Heat source side intermediate heat exchanger 26: Heat source side cycle 27: Load side intermediate heat exchanger 28: Load side heat exchanger 29: Pump 30: Load side cycle

Continuing on the front page (72) Inventor Norioka Okaza 1006 Kazuma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor Fumitoshi Nishiwaki 1006 Okadoma Kadoma Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd. (72) Inventor Tetsuji Kawakami 1006 Kadoma Kadoma, Kadoma City, Osaka Inside Matsushita Electric Industrial Co., Ltd.

Claims (5)

[Claims] At least a heat source side cycle in which a compressor, a heat source side heat exchanger, and a throttling device are connected by piping and a heat medium A is sealed therein, and at least a load side heat exchanger and conveying means are connected by piping. A load-side cycle which is connected and has a heat medium B sealed therein; the heat medium A and the heat medium B flowing into the heat cycle A;
And a direct heat exchanger that causes direct heat exchange by contacting the heat medium B, wherein the heat medium A circulates through the heat source side cycle via the direct heat exchanger, B circulates through the load side cycle via the direct heat exchanger, and a difference in solubility parameter between the heat medium A and the heat medium B is equal to or greater than a predetermined value. 2. The method according to claim 1, wherein the predetermined value is 2.10 (cal / c).
m ³⁾ refrigeration cycle apparatus according to claim 1, characterized in that ^0.5. 3. The heat medium A and the heat medium B in the direct heat exchanger in the heat source side cycle and the load side cycle in all or a part of the compressor, the expansion device, and the conveying means. 3 is controlled so as not to substantially mix with each other.
A refrigeration cycle apparatus according to item 1. 4. All or a part of the compressor, the expansion device, and the transporting means have a degree of superheating or supercooling of the heat medium A at the heat source side cycle outlet of the direct heat exchanger. The refrigeration cycle apparatus according to claim 1, wherein the refrigeration cycle apparatus is controlled to be equal to or more than a predetermined value x. 5. The superheat degree or supercool degree of the heat medium A at the outlet of the heat source side cycle of the direct heat exchanger, wherein all or a part of the compressor, the expansion device, and the transfer means are provided. The refrigeration cycle apparatus according to claim 1, wherein the refrigeration cycle apparatus is controlled to be equal to or less than a predetermined value y.