Refrigeration Cycle Equipment

Abstract

A refrigeration cycle device (1) comprises a refrigerant circuit (11) and an adsorbent. The refrigerant circuit (11) has a compressor (31) that compresses the refrigerant and an expansion mechanism (32) that reduces the pressure of the refrigerant. The refrigerant circuit (11) constitutes a vapor compression refrigeration cycle in which the refrigerant circulates. The adsorbent adsorbs and desorbs the refrigerant circulating through a first unit. The refrigerant circuit (11) has a high pressure region and a low pressure region. The refrigeration cycle device (1) is operated on the basis of at least one of a first condition and a second condition. The first condition is that the pressure of the refrigerant in the high pressure region is not more than the critical pressure of the refrigerant, and that the temperature of the refrigerant in the high pressure region is greater than the critical temperature of the refrigerant. The second condition is that the pressure of the refrigerant in the low pressure region is lower than a saturation pressure corresponding to a vaporization temperature of the refrigerant when the adsorbent does not adsorb or desorb the refrigerant.

Description

[Technical field]

[0001] This relates to a refrigeration cycle device. [Background technology]

[0002] Conventionally, a hybrid refrigeration system that combines a vapor compression refrigeration cycle and an adsorption refrigeration cycle has been used. Patent Document 1 (International Publication No. 2009 / 145278) discloses a hybrid refrigeration system that alternately cools and heats a pair of adsorbers in an adsorption refrigeration cycle to alternately adsorb and desorb a refrigerant in order to reduce the mechanical workload of a compressor in a vapor compression refrigeration cycle. Summary of the Invention [Problem to be solved by the invention]

[0003] A hybrid refrigeration system that controls adsorption and desorption of a refrigerant in an adsorption refrigeration cycle by utilizing pressure changes of a refrigerant circulating in a vapor compression refrigeration cycle has not been used conventionally. [Means for solving the problem]

[0004] A refrigeration cycle device according to a first aspect includes a first unit and an adsorbent. The first unit includes a compressor that compresses a refrigerant and an expansion mechanism that decompresses the refrigerant. The first unit constitutes a vapor compression refrigeration cycle in which the refrigerant circulates. The adsorbent adsorbs and desorbs the refrigerant circulating in the first unit. The first unit further includes a high pressure region and a low pressure region. In the high pressure region, the refrigerant flows after being compressed by the compressor and before being decompressed by the expansion mechanism. In the low pressure region, the refrigerant flows after being decompressed by the expansion mechanism and before being compressed by the compressor. The refrigeration cycle device is operated under at least one of a first condition and a second condition. In the first condition, the pressure of the refrigerant in the high pressure region is equal to or lower than the critical pressure of the refrigerant, and the temperature of the refrigerant in the high pressure region exceeds the critical temperature of the refrigerant. In the second condition, the pressure of the refrigerant in the low pressure region is lower than a saturation pressure that corresponds to the evaporation temperature of the refrigerant when the adsorbent does not adsorb and desorb the refrigerant.

[0005] The refrigeration cycle apparatus of the first aspect has a lower operating pressure than a refrigeration cycle apparatus having a vapor compression type refrigeration cycle and no adsorbent, and can utilize the heat of adsorption and desorption of the refrigerant. Therefore, the refrigeration cycle apparatus of the first aspect can reduce costs and improve the efficiency of the refrigeration cycle.

[0006] A refrigeration cycle device according to a second aspect includes a first unit and an adsorbent. The first unit includes a compressor that compresses a refrigerant and an expansion mechanism that decompresses the refrigerant. The first unit constitutes a vapor compression refrigeration cycle in which the refrigerant circulates. The adsorbent adsorbs and desorbs the refrigerant circulating in the first unit. The first unit further includes a high pressure region and a low pressure region. In the high pressure region, the refrigerant flows after being compressed by the compressor and before being decompressed by the expansion mechanism. In the low pressure region, the refrigerant flows after being decompressed by the expansion mechanism and before being compressed by the compressor. The refrigeration cycle device is operated under at least one of a first condition and a second condition. In the first condition, the pressure of the refrigerant in the high pressure region is equal to or lower than the critical pressure of the refrigerant, and the temperature of the refrigerant in the high pressure region exceeds a saturation temperature of the refrigerant corresponding to the pressure of the refrigerant in the high pressure region. In the second condition, the pressure of the refrigerant in the low pressure region is lower than a saturation pressure corresponding to an evaporation temperature of the refrigerant in a case where the adsorbent does not adsorb and desorb the refrigerant.

[0007] The refrigeration cycle apparatus of the second aspect has a lower operating pressure than a refrigeration cycle apparatus having a vapor compression type refrigeration cycle and no adsorbent, and can utilize the heat of adsorption and desorption of the refrigerant. Therefore, the refrigeration cycle apparatus of the second aspect can reduce costs and improve the efficiency of the refrigeration cycle.

[0008] A refrigeration cycle apparatus according to a third aspect is the refrigeration cycle apparatus according to the second aspect, wherein the pressure of the refrigerant in the high pressure region is equal to or lower than the saturation pressure of R32 corresponding to 65° C. in a vapor compression refrigeration cycle in which R32 circulates.

[0009] A refrigeration cycle apparatus according to a fourth aspect is the refrigeration cycle apparatus according to the second aspect, wherein the pressure of the refrigerant in the high pressure region is equal to or lower than the saturation pressure of R134a corresponding to 65° C. in a vapor compression refrigeration cycle in which R134a circulates.

[0010] A refrigeration cycle apparatus according to a fifth aspect is the refrigeration cycle apparatus according to any one of the second to fourth aspects, in which the adsorbent includes a metal organic framework including a metal ion and an organic ligand.

[0011] A refrigeration cycle apparatus according to a sixth aspect is the refrigeration cycle apparatus according to any one of the second to fifth aspects, in which the refrigerant is carbon dioxide.

[0012] A refrigeration cycle device according to a seventh aspect includes a first unit and an adsorbent. The first unit includes a compressor that compresses a refrigerant and an expansion mechanism that decompresses the refrigerant. The first unit constitutes a vapor compression type refrigeration cycle in which the refrigerant circulates. The adsorbent adsorbs and desorbs the refrigerant circulating in the first unit. The first unit further includes a high pressure region and a low pressure region. In the high pressure region, the refrigerant flows after being compressed by the compressor and before being decompressed by the expansion mechanism. In the low pressure region, the refrigerant flows after being decompressed by the expansion mechanism and before being compressed by the compressor. The refrigeration cycle device is operated under at least one of a first condition and a second condition. In the first condition, the pressure of the refrigerant in the high pressure region is lower than a saturation pressure corresponding to a condensation temperature of the refrigerant in a case where the adsorbent does not adsorb and desorb the refrigerant. In the second condition, the pressure of the refrigerant in the low pressure region is lower than a saturation pressure corresponding to an evaporation temperature of the refrigerant in a case where the adsorbent does not adsorb and desorb the refrigerant.

[0013] The refrigeration cycle apparatus of the seventh aspect has a lower operating pressure than a refrigeration cycle apparatus having a vapor compression type refrigeration cycle and no adsorbent, and can utilize the heat of adsorption and desorption of the refrigerant. Therefore, the refrigeration cycle apparatus of the seventh aspect can reduce costs and improve the efficiency of the refrigeration cycle.

[0014] A refrigeration cycle apparatus according to an eighth aspect is the refrigeration cycle apparatus according to the seventh aspect, in which the adsorbent includes a metal organic framework including a metal ion and an organic ligand.

[0015] A refrigeration cycle apparatus according to a ninth aspect is the refrigeration cycle apparatus according to the seventh or eighth aspect, in which the refrigerant is ammonia or propane. [Brief description of the drawings]

[0016] [Figure 1] FIG. 2 is a schematic diagram of a hybrid cycle provided in the refrigeration cycle device. [Diagram 2] 4 is a graph showing the relationship between the adsorption amount of the adsorbent and the pressure of the refrigerant. [Diagram 3] 4 is a graph showing the relationship between the adsorption amount of the adsorbent and the enthalpy of the refrigerant. [Figure 4] 4 is a graph showing the relationship between the pressure of a refrigerant and the enthalpy of the refrigerant. [Diagram 5] 4 is a graph showing an isotherm of a refrigerant adsorbed on an adsorbent. [Figure 6] FIG. 1 is a configuration diagram of an example of a refrigeration cycle device. [Figure 7] FIG. 2 is a Mollier diagram of the refrigerant in the first embodiment. [Figure 8] FIG. 11 is a Mollier diagram of a refrigerant in a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] (1) Overall structure The refrigeration cycle device 1 includes a hybrid cycle that combines a vapor compression cycle and an adsorption cycle. The vapor compression cycle is a vapor compression type refrigeration cycle, and is a heat pump cycle that utilizes the transfer of latent heat that occurs when a refrigerant evaporates and condenses. The adsorption cycle is an adsorption type refrigeration cycle, and is a heat pump cycle that utilizes the transfer of latent heat that occurs when a refrigerant is adsorbed to an adsorbent and when a refrigerant is desorbed from the adsorbent. The refrigeration cycle device 1 is, for example, an air conditioner or a refrigeration device.

[0018] 1, the refrigeration cycle device 1 includes a refrigerant circuit 11 and an adsorption circuit 12. The refrigerant circuit 11 constitutes a vapor compression cycle in which a refrigerant circulates. The adsorption circuit 12 constitutes an adsorption cycle in which an adsorbent circulates.

[0019] The refrigeration cycle apparatus 1 may have only one circuit having at least one of the functions of the refrigerant circuit 11 and the adsorption circuit 12. In this case, the refrigeration cycle apparatus 1 may have a circuit in which a mixture of a refrigerant and an adsorbent circulates. Alternatively, the refrigeration cycle apparatus 1 may have a circuit in which only the refrigerant circulates and which includes a mechanism for contacting the circulating refrigerant with the adsorbent. In this case, the adsorbent is not circulated.

[0020] The refrigeration cycle apparatus 1 may have two circuits, a circuit having the function of the refrigerant circuit 11 and a circuit having the function of the adsorption circuit 12. In this case, the refrigeration cycle apparatus 1 is provided with a mechanism for bringing the refrigerant circulating in the refrigerant circuit 11 into contact with the adsorbent circulating in the adsorption circuit 12. For the sake of explanation, in Fig. 1, the refrigerant circuit 11 and the adsorption circuit 12 are each depicted as an independent circuit.

[0021] The refrigeration cycle apparatus 1 has an adsorption section 21 and a desorption section 22. Both the adsorption section 21 and the desorption section 22 include a part of the refrigerant circuit 11 and a part of the adsorption circuit 12. The refrigerant can freely move between the refrigerant circuit 11 and the adsorption circuit 12 in the adsorption section 21 and the desorption section 22. The adsorbent cannot move between the refrigerant circuit 11 and the adsorption circuit 12. In the adsorption section 21, the refrigerant that flows from the refrigerant circuit 11 to the adsorption circuit 12 is adsorbed by the adsorbent flowing in the adsorption circuit 12. In the desorption section 22, the refrigerant desorbed from the adsorbent flowing in the adsorption circuit 12 flows from the adsorption circuit 12 into the refrigerant circuit 11.

[0022] The refrigerant circuit 11 has a compressor 31 and an expansion mechanism 32. The compressor 31 compresses the refrigerant circulating in the refrigerant circuit 11. The expansion mechanism 32 depressurizes the refrigerant circulating in the refrigerant circuit 11. The compressor 31 is, for example, a rotary compressor. The expansion mechanism 32 is, for example, an electronic expansion valve. In the refrigerant circuit 11, the refrigerant is compressed by the compressor 31, passes through the adsorption section 21, is depressurized by the expansion mechanism 32, passes through the desorption section 22, and is compressed again by the compressor 31.

[0023] The refrigerant circuit 11 has a high pressure region and a low pressure region. In the high pressure region, refrigerant compressed by the compressor 31 and before being decompressed by the expansion mechanism 32 flows. In the low pressure region, refrigerant decompressed by the expansion mechanism 32 and before being compressed by the compressor 31 flows. The high pressure region corresponds to a part of the refrigerant circuit 11 included in the adsorption unit 21. The low pressure region corresponds to a part of the refrigerant circuit 11 included in the desorption unit 22.

[0024] The refrigerant circulating in the refrigerant circuit 11 is carbon dioxide. The refrigerant may also be ammonia or propane.

[0025] The adsorption circuit 12 has a booster 41 and a pressure reducer 42. The booster 41 boosts the pressure of the adsorbent circulating through the adsorption circuit 12. The pressure reducer 42 reduces the pressure of the adsorbent circulating through the adsorption circuit 12. The booster 41 is, for example, a powder pump. The pressure reducer 42 is, for example, a powder valve. In the adsorption circuit 12, the adsorbent is boosted by the booster 41, passes through the adsorption section 21, is depressurized by the pressure reducer 42, passes through the desorption section 22, and is boosted again by the booster 41. Depending on the configuration of the refrigeration cycle apparatus 1, the adsorption circuit 12 may not have the booster 41 and the pressure reducer 42.

[0026] The adsorption circuit 12 may further include a heat exchanger 43. The heat exchanger 43 exchanges heat between the upstream side of the booster 41 and the upstream side of the pressure reducer 42. The heat exchanger 43 transfers part of the heat of the adsorbent flowing between the adsorption unit 21 and the pressure reducer 42 to the adsorbent flowing between the desorption unit 22 and the booster 41.

[0027] The adsorbent circulating through the adsorption circuit 12 includes a metal-organic framework including metal ions and organic ligands. A metal-organic framework (MOF) is a porous material having a very large specific surface area obtained by a reaction between metal ions and organic ligands. In the metal-organic framework, a polymer structure having numerous openings inside is obtained by linking the organic ligands with the metal ions. The metal-organic framework can adjust the opening size and topology by selecting and combining the metal ions and organic ligands, respectively. The metal-organic framework can adjust the opening size by selecting and combining the metal ions and organic ligands, and can selectively adsorb the target substance. The metal-organic framework is used, for example, as a porous material having the function of selectively storing and separating molecules and ions. In this embodiment, the metal-organic framework is used as an adsorbent for adsorbing and desorbing the refrigerant. The metal-organic framework is, for example, MOF-5 and MOF-200. The adsorbent is, for example, a powder of the metal-organic framework.

[0028] (2) Operation The adsorbent adsorbs and desorbs the refrigerant circulating in the refrigerant circuit 11. The adsorbent adsorbs and desorbs the refrigerant in response to changes in the pressure of the refrigerant circulating in the refrigerant circuit 11. Specifically, the adsorbent adsorbs the refrigerant under high pressure and desorbs the refrigerant under low pressure.

[0029] The high-pressure region of the refrigerant circuit 11 is filled with refrigerant at a pressure pH and a temperature TH. The low-pressure region of the refrigerant circuit 11 is filled with refrigerant at a pressure pL and a temperature TL. The pressure pH is higher than the pressure pL. The temperature TH is higher than the temperature TL. The adsorbent adsorbs the refrigerant in the high-pressure region of the refrigerant circuit 11. The adsorbent desorbs the refrigerant in the low-pressure region of the refrigerant circuit 11. In the adsorption section 21, the refrigerant flowing through the high-pressure region of the refrigerant circuit 11 flows into the adsorption circuit 12 and is adsorbed by the adsorbent. In the desorption section 22, the refrigerant desorbed from the adsorbent flowing through the adsorption circuit 12 flows into the low-pressure region of the refrigerant circuit 11.

[0030] The operation of the heat pump cycle of the refrigeration cycle device 1 will be described with reference to FIG. 1-4. FIG. 1-4 shows the refrigerant cycle a→b→c→d→a of the refrigerant circuit 11 and the adsorbent cycle a'→b'→c'→d'→a' of the adsorption circuit 12. The graph in FIG. 2 shows the adsorption amount, which is the mass of the refrigerant adsorbed on the adsorbent per unit mass, and the change in the pressure of the refrigerant adsorbed on the adsorbent in the heat pump cycle. The graph in FIG. 3 shows the adsorption amount of the adsorbent and the change in the enthalpy of the refrigerant adsorbed on the adsorbent in the heat pump cycle. The graph in FIG. 4 shows the change in the refrigerant pressure and the enthalpy of the refrigerant in the heat pump cycle. In the refrigeration cycle device 1, it is assumed that heat can freely flow between the refrigerant circuit 11 and the adsorption circuit 12.

[0031] In the refrigerant circuit 11, the refrigerant is compressed by the compressor 31 (a→b). In the adsorption circuit 12, the adsorbent is boosted by the booster 41 (a'→b'). As a result, the pressure of the refrigerant and the adsorbent increases from pL to pH. In this process, a part of the heat Q1 generated by the adiabatic compression of the refrigerant is given to the adsorbent. In other words, the refrigerant is cooled by giving heat to the adsorbent while being compressed. As a result, the temperature of the refrigerant and the adsorbent increases from TL to TH.

[0032] Next, in the adsorption unit 21, the refrigerant is gradually adsorbed into the adsorbent while releasing heat Q2 (b'→c'). In this process, the adsorption amount of the adsorbent increases from mL to mH. As a result, in the adsorption unit 21, most of the refrigerant in the refrigerant circuit 11 is adsorbed into the adsorbent in the adsorption circuit 12. As shown by the hatched arrow in the adsorption unit 21 in FIG. 1, in the adsorption unit 21, the refrigerant in the refrigerant circuit 11 moves to the adsorption circuit 12 and is adsorbed into the adsorbent.

[0033] Next, in the adsorption circuit 12, the adsorbent is depressurized by the pressure reducer 42 (c'→d'). As a result, the pressure of the adsorbent decreases from pH to pL. In this process, the temperature of the adsorbent decreases from TH to TL due to isenthalpic expansion of the refrigerant desorbed from the adsorbent. In addition, the depressurized adsorbent in the adsorption circuit 12 is cooled due to the temperature difference between the refrigerant and the adsorbent, and provides heat Q3 to the refrigerant in the refrigerant circuit 11. In addition, heat Q5 is provided by the heat exchanger 43 from the adsorbent before it is depressurized to the adsorbent before it is pressurized.

[0034] Next, in the desorption section 22, the refrigerant is gradually desorbed from the adsorbent while absorbing heat Q4 (d'→a'). During this process, the adsorption amount of the adsorbent decreases from mH to mL. As a result, most of the refrigerant adsorbed to the adsorbent in the adsorption circuit 12 is desorbed and flows into the refrigerant circuit 11. As shown by the hatched arrow in the desorption section 22 in FIG. 1, in the desorption section 22, the refrigerant desorbed from the adsorbent in the adsorption circuit 12 moves to the refrigerant circuit 11.

[0035] As shown in FIG. 2, in the adsorption process (b'→c') in which the refrigerant is adsorbed onto the adsorbent, the pressure is pH, and the adsorption amount of the adsorbent increases from mL to mH. In the desorption process (d'→a') in which the refrigerant is desorbed from the adsorbent, the pressure is pL, and the adsorption amount of the adsorbent decreases from mH to mL. As shown in FIG. 3, in the adsorption process, the enthalpy decreases by Δh1. In the desorption process, the enthalpy increases by Δh2. In the adsorption process, the heat Q2 released from the adsorption section 21 is proportional to Δh1. In the desorption process, the heat Q4 absorbed by the desorption section 22 is proportional to Δh2.

[0036] The amount of change in enthalpy caused by heat exchange by the heat exchanger 43 is Δh3. The amount of change in enthalpy caused by heating the adsorbent during the adsorbent pressurization process (a'→b') is Δh4. The amount of change in enthalpy caused by cooling the adsorbent during the adsorbent depressurization process (c'→d') is Δh5. As shown in FIG. 4, the amount of change in total enthalpy during the refrigerant compression process (a→b) is represented by Δh4-Δh3. The amount of change in total enthalpy during the adsorbent depressurization process (c'→d') is represented by Δh5-Δh3. In FIG. 4, the state change of the refrigerant during adiabatic compression is indicated by dashed arrows, and the state change of the refrigerant during isoenthalpic expansion is indicated by dashed arrows.

[0037] FIG. 5 shows isotherms during adsorption and desorption of a refrigerant suitable for the heat pump cycle of the refrigeration cycle device 1. In FIG. 5, the isotherm at temperature TH is shown by a solid line, and the isotherm at temperature TL is shown by a dashed line. In the adsorption process (b'→c'), when the refrigerant is adsorbed to the adsorbent at pressure pH and temperature TH, the isotherm at temperature TH preferably indicates that the adsorption amount of the adsorbent increases from mL to mH at a pressure between pL and pH. In the desorption process (d'→a'), when the refrigerant is desorbed from the adsorbent at pressure pL and temperature TL, the isotherm at temperature TL preferably indicates that the adsorption amount of the adsorbent decreases from mH to mL at a pressure between pL and pH.

[0038] (3) Detailed configuration A specific configuration of the refrigeration cycle device 1 shown in FIG. 1 will be described with reference to FIG.

[0039] The refrigeration cycle apparatus 301 shown in Fig. 6 has a refrigerant circuit 311 in which a refrigerant circulates. The refrigerant circuit 311 has the functions of both the refrigerant circuit 11 and the adsorption circuit 12 in Fig. 1. The adsorbent flows together with the refrigerant through a part of the refrigerant circuit 311. In other words, in the refrigeration cycle apparatus 301, a mixture of the refrigerant and the adsorbent circulates through the refrigerant circuit 311.

[0040] The refrigerant circuit 311 has a compressor 331, an expansion mechanism 332, a first heat exchanger 333, a second heat exchanger 334, a switching unit 335, a first fan 336, a second fan 337, a booster 341, and a separator 351. The compressor 331 corresponds to the compressor 31 in Fig. 1. The booster 341 corresponds to the booster 41 in Fig. 1. The expansion mechanism 332 has the functions of both the expansion mechanism 32 and the decompressor 42 in Fig. 1.

[0041] The switching unit 335 switches the flow direction of the mixture of the refrigerant and the adsorbent circulating in the refrigerant circuit 311. The switching unit 335 is, for example, a four-way switching valve. The switching unit 335 switches between a first mode of the flow direction shown by the solid line in FIG. 6 and a second mode of the flow direction shown by the dashed line in FIG. 6. In the first mode, the discharge side of the compressor 331 and the booster 341 are connected to the first heat exchanger 333, and the suction side of the compressor 331 and the booster 341 are connected to the second heat exchanger 334. In the second mode, the discharge side of the compressor 331 and the booster 341 are connected to the second heat exchanger 334, and the suction side of the compressor 331 and the booster 341 are connected to the first heat exchanger 333.

[0042] The separator 351 is provided between the suction sides of the compressor 331 and the booster 341 and the switching unit 335 .

[0043] The separator 351 separates a mixture of a low-pressure refrigerant and an adsorbent circulating in the refrigerant circuit 311 into the refrigerant and the adsorbent. The separator 351 separates the refrigerant and the adsorbent by, for example, centrifugation. The refrigerant separated by the separator 351 is compressed in the compressor 331. The adsorbent separated by the separator 351 is boosted by the booster 341. As shown in FIG. 6, the adsorbent boosted by the booster 341 merges with the refrigerant compressed in the compressor 331. After the merger, the refrigerant and the adsorbent are sent to the switching unit 335. In this way, the refrigerant circuit 311 branches in the separator 351 and merges between the compressor 331 / booster 341 and the switching unit 335.

[0044] In the first heat exchanger 333, the high-pressure refrigerant is adsorbed to the adsorbent in the first mode, and the low-pressure refrigerant is desorbed from the adsorbent in the second mode. In the second heat exchanger 334, the low-pressure refrigerant is desorbed from the adsorbent in the first mode, and the high-pressure refrigerant is adsorbed to the adsorbent in the second mode. In the first heat exchanger 333 and the second heat exchanger 334, the refrigerant is heated by being adsorbed to the adsorbent, or the refrigerant is cooled by being desorbed from the adsorbent. As a result, in the first heat exchanger 333 and the second heat exchanger 334, heat exchange is performed between the heated or cooled refrigerant and the air. The first fan 336 sends the air that has been heat exchanged in the first heat exchanger 333 to a predetermined location. The second fan 337 sends the air that has been heat exchanged in the second heat exchanger 334 to a predetermined location.

[0045] In this way, in the refrigeration cycle apparatus 301, the refrigerant is heated or cooled in the process in which the mixture of the refrigerant and the adsorbent circulates in the refrigerant circuit 311, and the air that has exchanged heat with the refrigerant is sent to a predetermined location. A case in which the refrigeration cycle apparatus 301 is an air conditioner will be described. The first heat exchanger 333 is an indoor heat exchanger, and the second heat exchanger 334 is an outdoor heat exchanger. When the refrigeration cycle apparatus 301 performs a heating operation, the refrigerant is adsorbed to the adsorbent in the first heat exchanger 333 by switching to the first mode, and the refrigerant is heated. The air that has exchanged heat with the refrigerant and been heated is sent to a predetermined location by the first fan 336.

[0046] The refrigeration cycle apparatus 301 may further include a member that separates the mixture of the high-pressure refrigerant and the adsorbent, which circulates in the refrigerant circuit 311, into the refrigerant and the adsorbent. In this case, the separated refrigerant is depressurized by a member corresponding to the expansion mechanism 332 in Fig. 6, and the separated adsorbent is depressurized by a member corresponding to the pressure reducer 42 in Fig. 1.

[0047] The specific configuration of the refrigeration cycle apparatus 1 shown in Fig. 1 is not limited to the refrigeration cycle apparatus 301 shown in Fig. 6. For example, the refrigeration cycle apparatus 1 may have one circuit in which a mixture of a refrigerant and an adsorbent circulates, without having components corresponding to the booster 341 and the separator 351 of the refrigeration cycle apparatus 301.

[0048] The refrigeration cycle device 1 may have two circuits, a refrigerant circuit in which the refrigerant circulates and an adsorbent circuit in which the adsorbent circulates. In this case, the refrigeration cycle device 1 has a configuration for allowing the refrigerant flowing through the refrigerant circuit to freely enter and exit the adsorbent circuit. For example, the refrigeration cycle device 1 has a mixing section in which the refrigerant circuit and the adsorbent circuit are separated by a gas-permeable membrane through which the refrigerant can pass but the adsorbent cannot. The mixing section corresponds to the adsorption section 21 and the desorption section 22 shown in FIG. 1. In the mixing section, the refrigerant and the adsorbent are mixed, and the refrigerant is adsorbed or desorbed.

[0049] The refrigeration cycle device 1 may have a configuration in which two adsorption units (a first adsorption unit and a second adsorption unit) are installed in a refrigerant circuit through which the refrigerant circulates. The first adsorption unit and the second adsorption unit have adsorbents that come into contact with the refrigerant circulating through the refrigerant circuit. In this case, the refrigeration cycle device 1 has a configuration that is switchable between a first mode in which the first adsorption material adsorbs the refrigerant and the second adsorption material desorbs the refrigerant, and a second mode in which the first adsorption material desorbs the refrigerant and the second adsorption material adsorbs the refrigerant.

[0050] (4) Operating conditions The refrigeration cycle device 1 is operated so that at least one of the first condition and the second condition is satisfied. Next, specific examples of the first condition and the second condition will be described with reference to a Mollier diagram (ph diagram) showing the state of the refrigerant in the refrigeration cycle. In Fig. 7 and Fig. 8, the saturated liquid line L1, the dry saturated vapor line L2, and the critical point CP of the refrigerant are drawn. The critical point CP is the high-pressure side end point of the saturated liquid line L1 and the dry saturated vapor line L2. In Fig. 7, isotherms at temperatures TH, TC, and TS are drawn by dashed lines.

[0051] (4-1) First Example In this embodiment, carbon dioxide is used as the refrigerant in the refrigeration cycle device 1. The first and second conditions are as follows. · First condition: The pressure of the refrigerant in the high pressure region is equal to or lower than the critical pressure of the refrigerant, and the temperature of the refrigerant in the high pressure region exceeds the critical temperature of the refrigerant. · Second condition: The pressure of the refrigerant in the low pressure region is lower than the saturation pressure, which corresponds to the evaporation temperature of the refrigerant when the adsorbent does not adsorb or desorb the refrigerant.

[0052] 7, the refrigeration cycle C1 of the refrigeration cycle device 1 is shown by a solid line, and the refrigeration cycle C2 of the refrigeration cycle device equipped with only a vapor compression cycle is shown by a dashed line. The refrigeration cycle C1 shows each state of the cycle a→b→c→d→a of the refrigerant of the refrigerant circuit 11 in FIG.

[0053] Under the first condition, the pressure PH of the refrigerant in the high pressure region of the refrigeration cycle C1 is equal to or lower than the critical pressure PC of the refrigerant. The critical pressure PC is the pressure at the critical point CP. Also, under the first condition, the temperature TH of the refrigerant in the high pressure region of the refrigeration cycle C1 exceeds the critical temperature TC of the refrigerant. The temperature TH is the temperature of the high temperature, high pressure refrigerant compressed by the compressor 31, and is the temperature of the refrigerant in state b of the refrigeration cycle C1. The critical temperature TC is the temperature at the critical point CP. In FIG. 7, the temperature TH indicated by the isotherm passing through state b is higher than the temperature TC indicated by the isotherm passing through the critical point CP.

[0054] In the second condition, the refrigerant pressure PL in the low pressure region of the refrigeration cycle C1 is lower than the saturation pressure PL' corresponding to the evaporation temperature of the refrigerant when the adsorbent does not adsorb or desorb the refrigerant. The saturation pressure PL' corresponds to the pressure in the low pressure region of the refrigeration cycle C2.

[0055] The value of the pressure PH of the refrigerant in the high pressure region of the refrigeration cycle C1 may be set appropriately. For example, the pressure PH is set to a saturation pressure of R32 equivalent to 65°C or less in a vapor compression refrigeration cycle in which R32 circulates. Also, the pressure PH is set to a saturation pressure of R134a equivalent to 65°C or less in a vapor compression refrigeration cycle in which R134a circulates.

[0056] (4-2) Second Example In this embodiment, the refrigerant used by the refrigeration cycle device 1 is propane. The first and second conditions are as follows. · First condition: The pressure of the refrigerant in the high pressure region is lower than the saturation pressure, which corresponds to the condensation temperature of the refrigerant when the adsorbent does not adsorb or desorb the refrigerant. · Second condition: The pressure of the refrigerant in the low pressure region is lower than the saturation pressure, which corresponds to the evaporation temperature of the refrigerant when the adsorbent does not adsorb or desorb the refrigerant.

[0057] 8, the refrigeration cycle C3 of the refrigeration cycle device 1 is shown by a solid line, and the refrigeration cycle C4 of the refrigeration cycle device equipped with only a vapor compression cycle is shown by a dashed line. The refrigeration cycle C3 shows each state of the cycle a→b→c→d→a of the refrigerant of the refrigerant circuit 11 in FIG.

[0058] In the first condition, the refrigerant pressure PH in the high pressure region of the refrigeration cycle C3 is lower than the saturation pressure PH' corresponding to the condensation temperature of the refrigerant when the adsorbent does not adsorb or desorb the refrigerant. The saturation pressure PH' corresponds to the pressure in the high pressure region of the refrigeration cycle C4.

[0059] In the second condition, the refrigerant pressure PL in the low pressure region of the refrigeration cycle C3 is lower than the saturation pressure PL' corresponding to the evaporation temperature of the refrigerant when the adsorbent does not adsorb or desorb the refrigerant. The saturation pressure PL' corresponds to the pressure in the low pressure region of the refrigeration cycle C4.

[0060] (5) Features In FIG. 7 and FIG. 8, the working pressure of the refrigeration cycle device 1 is PH, and the working pressure of the conventional refrigeration cycle device is PH'. The working pressure PH is lower than the working pressure PH'. Therefore, the working pressure of the refrigeration cycle device 1 is smaller than that of a conventional refrigeration cycle device having a vapor compression type refrigeration cycle and no adsorbent. For example, when the refrigerant is carbon dioxide, as shown in FIG. 7, the working pressure PH' of the conventional refrigeration cycle device is about 10 MPa, and the working pressure PH of the refrigeration cycle device 1 is about 1.5 MPa. The working pressure is the pressure of the compressed refrigerant in the refrigeration cycle. The higher the working pressure, the greater the mechanical work load of the compressor, and the higher the withstand pressure (design pressure) required for the components constituting the refrigerant circuit, such as the casing of the compressor. Therefore, the higher the working pressure, the higher the cost of electricity for driving the compressor and the cost of the components constituting the system tend to be.

[0061] Therefore, the refrigeration cycle device 1 can be operated at a lower operating pressure than conventional refrigeration cycle devices, and therefore manufacturing and operating costs can be reduced. In addition, by lowering the design pressure of the refrigeration cycle device 1, components such as the compressor casing can be made more compact, and the reliability of the system can be improved.

[0062] Furthermore, when the refrigeration cycle apparatus 1 is an air conditioner, the refrigeration cycle apparatus 1 can increase the heating and cooling capacity by utilizing the heat of adsorption and desorption of the refrigerant for heating and cooling. Therefore, the refrigeration cycle apparatus 1 can improve the efficiency of the refrigeration cycle and reduce the operating cost compared to conventional refrigeration cycle apparatuses by controlling the heat of adsorption and desorption of the refrigerant.

[0063] (6) Variations (6-1) Variation A In the first embodiment, the first condition may be a condition in which the pressure of the refrigerant in the high pressure region is equal to or lower than the critical pressure of the refrigerant, and the temperature of the refrigerant in the high pressure region exceeds the saturation temperature of the refrigerant corresponding to the pressure of the refrigerant in the high pressure region.

[0064] In this first condition, the refrigerant pressure PH in the high pressure region of the refrigeration cycle C1 is equal to or lower than the critical pressure PC of the refrigerant. The refrigerant temperature TH in the high pressure region of the refrigeration cycle C1 exceeds the saturation temperature TS of the refrigerant corresponding to the pressure of the refrigerant in the high pressure region. The temperature TH is the temperature of the high temperature, high pressure refrigerant compressed by the compressor 31, and is the temperature of the refrigerant in state b of the refrigeration cycle C1. As shown in Fig. 7, the saturation temperature TS corresponds to the temperature at the point where the line of the refrigerant pressure PH in the high pressure region of the refrigeration cycle C1 intersects with the dry saturated vapor line L2.

[0065] (6-2) Variation B In the second embodiment, the refrigerant used by the refrigeration cycle device 1 may be ammonia.

[0066] (6-3) Variation C The adsorbent used in the refrigeration cycle apparatus 1, 301 is a metal-organic framework. However, a material other than the metal-organic framework may be used as the adsorbent.

[0067] Although the embodiments of the present disclosure have been described above, it will be understood that various changes in form and details can be made without departing from the spirit and scope of the present disclosure described in the claims. [Explanation of symbols]

[0068] 1,301: Refrigeration cycle equipment 11,311: Refrigerant circuit (first unit) 31,331: Compressor 32,332: Expansion mechanism [Prior art documents] [Patent documents]

[0069] [Patent Document 1] International Publication No. 2009 / 145278

Claims

1. a first unit (11, 311) including a compressor (31, 331) for compressing a refrigerant and an expansion mechanism (32, 332) for reducing the pressure of the refrigerant, and constituting a vapor compression refrigeration cycle in which the refrigerant circulates; an adsorbent that adsorbs and desorbs the refrigerant circulating in the first unit; Equipped with The first unit is a high-pressure region through which the refrigerant flows after being compressed by the compressor and before being decompressed by the expansion mechanism; a low-pressure region through which the refrigerant flows after being decompressed by the expansion mechanism and before being compressed by the compressor; and A first condition in which the pressure of the refrigerant in the high pressure region is equal to or lower than the critical pressure of the refrigerant and the temperature of the refrigerant in the high pressure region exceeds the critical temperature of the refrigerant; and a second condition, in which the pressure of the refrigerant in the low pressure region is lower than a saturation pressure corresponding to an evaporation temperature of the refrigerant in a case in which the adsorbent does not adsorb and desorb the refrigerant; The vehicle is operated under at least one of the following conditions: Refrigeration cycle device (1, 301).

2. a first unit (11, 311) including a compressor (31, 331) for compressing a refrigerant and an expansion mechanism (32, 332) for reducing the pressure of the refrigerant, and constituting a vapor compression refrigeration cycle in which the refrigerant circulates; an adsorbent that adsorbs and desorbs the refrigerant circulating in the first unit; Equipped with The first unit is a high-pressure region through which the refrigerant flows after being compressed by the compressor and before being decompressed by the expansion mechanism; a low-pressure region through which the refrigerant flows after being decompressed by the expansion mechanism and before being compressed by the compressor; and A first condition in which the pressure of the refrigerant in the high pressure region is equal to or lower than the critical pressure of the refrigerant, and the temperature of the refrigerant in the high pressure region exceeds a saturation temperature of the refrigerant corresponding to the pressure of the refrigerant in the high pressure region; and a second condition, in which the pressure of the refrigerant in the low pressure region is lower than a saturation pressure corresponding to an evaporation temperature of the refrigerant in a case in which the adsorbent does not adsorb and desorb the refrigerant; The vehicle is operated under at least one of the following conditions: Refrigeration cycle device (1, 301).

3. The pressure of the refrigerant in the high pressure region is equal to or lower than the saturation pressure of R32 corresponding to 65°C in a vapor compression refrigeration cycle in which R32 circulates. The refrigeration cycle device according to claim 2.

4. The pressure of the refrigerant in the high pressure region is equal to or lower than the saturation pressure of R134a corresponding to 65°C in a vapor compression refrigeration cycle in which R134a circulates. The refrigeration cycle device according to claim 2.

5. The adsorbent includes a metal organic framework including a metal ion and an organic ligand. The refrigeration cycle device according to any one of claims 2 to 4.

6. The refrigerant is carbon dioxide. The refrigeration cycle device according to any one of claims 2 to 5.

7. a first unit (11, 311) including a compressor (31, 331) for compressing a refrigerant and an expansion mechanism (32, 332) for reducing the pressure of the refrigerant, and constituting a vapor compression refrigeration cycle in which the refrigerant circulates; an adsorbent that adsorbs and desorbs the refrigerant circulating in the first unit; Equipped with The first unit is a high-pressure region through which the refrigerant flows after being compressed by the compressor and before being decompressed by the expansion mechanism; a low-pressure region through which the refrigerant flows after being decompressed by the expansion mechanism and before being compressed by the compressor; and A first condition in which the pressure of the refrigerant in the high pressure region is lower than a saturation pressure corresponding to a condensation temperature of the refrigerant when the adsorbent does not adsorb and desorb the refrigerant; and a second condition, in which the pressure of the refrigerant in the low pressure region is lower than a saturation pressure corresponding to an evaporation temperature of the refrigerant in a case in which the adsorbent does not adsorb and desorb the refrigerant; The vehicle is operated under at least one of the following conditions: Refrigeration cycle device (1, 301).

8. The adsorbent includes a metal organic framework including a metal ion and an organic ligand. The refrigeration cycle device according to claim 7.

9. The refrigerant is ammonia or propane; The refrigeration cycle device according to claim 7 or 8.

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