Heat exchanger, refrigerant circulation device, and hot water supply device

Abstract

Provided are a heat exchanger capable of ensuring heat exchange performance even if there is a difference in pressure when two fluids flow in, and a refrigerant circulation device and a hot water supply device using the heat exchanger. A first heat exchanger (100) is provided with a first heat transfer plate (110) and a second heat transfer plate (120). The second heat transfer plate has second flow ports (121a, 121b), second through-holes (122a, 122b), a second heat transfer region (123), and second connection sections (125a, 125b). A second fluid having a boiling point lower than that of the first fluid is introduced into and discharged from the second flow port. The second through hole allows the first fluid to pass through in the thickness direction. In the second heat transfer region, the second fluid exchanges heat with the first fluid while passing through the second heat transfer region. One end of the second connecting part is connected with the second circulation opening, and the other end is connected with the second heat transfer area. The second flow port is formed at a position opposite to the second heat transfer region across the second through hole. The second connection part is formed so as to bypass the outside of the second through-hole, and is provided with second protrusions (127a, 127b).

Description

Technical Field

[0001] The invention relates to a heat exchanger, a refrigerant circulation device and a hot water supplier. Background Art

[0002] A plate heat exchanger is known in which a plurality of heat transfer plates are stacked at predetermined intervals to alternately form flow paths for a first fluid and flow paths for a second fluid in a stacking direction to perform heat exchange between the two fluids.

[0003] Patent document 1 (Japanese Patent Publication No. 2012-512382) mainly discloses a heat transfer plate (heat exchange plate) and a heat exchanger using the heat transfer plate, wherein the heat transfer plate has: two flow ports for allowing a fluid on one side to flow in or out; a heat transfer area having a plurality of grooves for allowing the inflowing fluid to perform heat exchange; a connecting portion (distribution area) having grooves connecting the flow ports and the heat transfer area; and a pair of through holes for allowing the fluid on the other side to pass through. Summary of the invention

[0004] Problems to be solved by the invention

[0005] In the heat exchanger of Patent Document 1, the length of the flow path for the first fluid to flow is the same as the length of the flow path for the second fluid to flow. Therefore, the two fluids generate the same degree of pressure loss inside the heat exchanger. When comparing the pressure reduction ratio caused by the pressure loss generated in this way, the pressure of the fluid with the lower pressure when it flows into the two fluids is reduced at a relatively large ratio. As a result, there is a problem that the heat exchanger cannot fully exert its heat exchange performance.

[0006] The present disclosure provides a heat exchanger capable of ensuring heat exchange performance even when there is a difference in pressure when two fluids flow in, and a refrigerant circulation device and a hot water supplier using the heat exchanger.

[0007] Means for solving problems

[0008] The heat exchanger according to the first aspect includes a first heat transfer plate and a second heat transfer plate stacked on each other.

[0009] The first heat transfer plate has a first flow port, a first through hole, a first heat transfer area and a first connecting portion.

[0010] The first flow port introduces or outputs the first fluid. The first through hole allows a second fluid with a lower boiling point than the first fluid to pass through in the thickness direction. The first heat transfer region is a region where the first fluid flowing in from the first flow port passes through while exchanging heat with the second fluid. One end of the first connection portion is connected to the first flow port, and the other end is connected to the first heat transfer region.

[0011] The second heat transfer plate has a second flow port, a second through hole, a second heat transfer area and a second connecting portion.

[0012] The second flow port is connected to the first through hole and introduces or guides the second fluid. The second through hole allows the first fluid to pass through in the thickness direction. The second heat transfer area is an area where the second fluid flowing in from the second flow port passes through while exchanging heat with the first fluid. One end of the second connecting portion is connected to the second flow port, and the other end is connected to the second heat transfer area.

[0013] The second flow port is formed at a position opposite to the second heat transfer region across the second through hole. The second connection portion is formed so as to bypass the outside of the second through hole and is provided with a second protrusion.

[0014] In the present heat exchanger, the second connection part is formed in a manner of bypassing the outside of the second through hole. In other words, the length of the flow path of the first connection part through which the first fluid passes is formed to be shorter than the length of the flow path of the second connection part through which the second fluid having a lower boiling point than the first fluid passes. Therefore, the pressure loss generated in the first fluid when passing through the first connection part can be made less than the pressure loss generated in the second fluid when passing through the second connection part. Thus, the pressure of the first fluid is suppressed from decreasing at a greater ratio. Therefore, according to the present heat exchanger, even if there is a difference in pressure when the two fluids flow in, the heat exchange performance can be ensured.

[0015] Heat exchanger according to a second aspect In the heat exchanger according to the first aspect, the second protrusion is linear in plan view.

[0016] A heat exchanger according to a third aspect is the heat exchanger according to the first aspect or the second aspect, wherein the second connecting portion is linear in a plan view.

[0017] A heat exchanger according to a fourth aspect is the heat exchanger according to the first aspect, wherein the second protrusion has a circular shape in a plan view.

[0018] A heat exchanger according to a fifth aspect is the heat exchanger according to the first aspect, wherein the second protrusion has a triangular shape in a plan view.

[0019] A heat exchanger according to a sixth aspect is the heat exchanger according to the first aspect, wherein the second protrusion has a quadrilateral shape in a plan view.

[0020] A heat exchanger according to a seventh aspect is the heat exchanger according to the first aspect, wherein the second protrusion has a teardrop shape in a plan view.

[0021] A heat exchanger according to an eighth aspect is the heat exchanger according to the first aspect, wherein the first connection portion is formed so that a flow path cross-sectional area increases from the first flow port toward the first heat transfer region.

[0022] According to the heat exchanger, the pressure loss of the first fluid passing through the first connection portion is further reduced, so that the pressure of the first fluid can be further suppressed from decreasing at a large rate, and the heat exchange performance can be more effectively ensured.

[0023] A heat exchanger according to a ninth aspect is the heat exchanger according to the eighth aspect, wherein the first connection portion is provided with a first protrusion, and the first protrusion is linear in a plan view.

[0024] A heat exchanger according to a tenth aspect is the heat exchanger according to the eighth aspect, wherein the first connection portion is provided with a first protrusion, and the first protrusion has a circular shape in a plan view.

[0025] The heat exchanger according to an eleventh aspect is the heat exchanger according to the eighth aspect, wherein the first connection portion is provided with a first protrusion, and the first protrusion has a triangular shape in a plan view.

[0026] A heat exchanger according to a twelfth aspect is the heat exchanger according to the eighth aspect, wherein the first connection portion is provided with a first protrusion, and the first protrusion has a quadrilateral shape in a plan view.

[0027] A heat exchanger according to a thirteenth aspect is the heat exchanger according to the eighth aspect, wherein the first connection portion is provided with a first protrusion, and the first protrusion has a teardrop shape in a plan view.

[0028] The heat exchanger of the fourteenth aspect is a heat exchanger of any one of the first to thirteenth aspects, and is provided with a partition wall. The partition wall is a plate-shaped member stacked between the first heat transfer plate and the second heat transfer plate. The first connecting portion is formed so that, in a cross section orthogonal to the flow direction of the first fluid, when the length of the first separation portion that separates adjacent first connecting portions from each other in contact with the partition wall is La1 and the interval between adjacent first separation portions is P1, the relationship of 0.005<La1 / P1<0.15 is satisfied.

[0029] The first connection portion is formed to satisfy the above relationship, thereby preventing the force received by the partition wall from the first fluid passing through the first connection portion from exceeding the pressure resistance strength.

[0030] Heat exchanger according to a fifteenth aspect In the heat exchanger according to the fourteenth aspect, the first connection portion is formed so as to satisfy a relationship of 0.005<La1 / P1<0.05.

[0031] According to the heat exchanger, the first connection portion is formed to satisfy the above relationship, thereby more effectively preventing the force received by the partition wall from the first fluid passing through the first connection portion from exceeding the pressure resistance strength.

[0032] The heat exchanger of the sixteenth aspect is a heat exchanger of any one of the first to fifteenth aspects, and is provided with a partition wall. The second connecting portion is formed so that, in a cross section orthogonal to the flow direction of the second fluid, when the length of the second separation portion or the protrusion portion that separates the adjacent second connecting portions from each other and the contact with the partition wall is La2 and the interval between the adjacent second separation portions or the second protrusion portions is P2, the relationship of 0.005<L2 / P2<0.15 is satisfied.

[0033] According to the heat exchanger, the second connection portion is formed to satisfy the above relationship, thereby preventing the force received by the partition wall from the second fluid passing through the second connection portion from exceeding the pressure resistance strength.

[0034] Heat Exchanger of a Seventeenth Aspect In the heat exchanger of the sixteenth aspect, the second connection portion is formed to satisfy a relationship of 0.02<L2 / P2<0.15.

[0035] According to the heat exchanger, the second connection portion is formed to satisfy the above relationship, thereby more effectively preventing the force received by the partition wall from the second fluid passing through the second connection portion from exceeding the pressure resistance strength.

[0036] A refrigeration cycle device according to an eighteenth aspect includes: the heat exchanger according to any one of the first to seventeenth aspects; a first fluid circuit through which a first fluid circulates; and a second fluid circuit through which a second fluid circulates.

[0037] A hot water supply device according to a nineteenth aspect includes: the heat exchanger according to any one of the first to seventeenth aspects; a first fluid circuit in which a first fluid circulates; and a second fluid circuit in which a second fluid circulates. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 1 is a schematic diagram showing the configuration of a refrigeration cycle device 1 including a first heat exchanger 100 .

[0039] Figure 2 It is an exploded perspective view of the first heat exchanger 100 .

[0040] Figure 3 is a plan view of the first heat transfer plate 110 .

[0041] Figure 4 It is an enlarged view of the upper end portion and the periphery of the first heat transfer plate 110 .

[0042] Figure 5 is along Figure 4 A cross-sectional view of the portion cut along the line AA' in FIG.

[0043] Figure 6 is a plan view of the second heat transfer plate 120 .

[0044] Figure 7 It is an enlarged view of the upper end portion and the periphery of the second heat transfer plate 120 .

[0045] Figure 8 is along Figure 7 A cross-sectional view of the portion cut along the BB' line.

[0046] Fig. 9 This is an enlarged view of the upper end portion and the periphery of the second heat transfer plate 120 of the first heat exchanger 100 according to Modification A.

[0047] Fig.10 This is an enlarged view of the upper end portion and the periphery of the second heat transfer plate 120 of the first heat exchanger 100 according to another example of Modification A.

[0048] Fig.11 This is an enlarged view of the upper end portion and the periphery of the second heat transfer plate 120 of the first heat exchanger 100 according to another example of Modification A.

[0049] Fig.12 This is an enlarged view of the upper end portion and the periphery of the second heat transfer plate 120 of the first heat exchanger 100 according to another example of Modification A.

[0050] Fig.13 This is an enlarged view of the upper end portion and the periphery of the first heat transfer plate 110 of the first heat exchanger 100 according to Modification B.

[0051] Fig.14 This is an enlarged view of the upper end portion and the periphery of the first heat transfer plate 110 of the first heat exchanger 100 according to Modification F.

[0052] Fig.15 This is an enlarged view of the upper end portion and the periphery of the first heat transfer plate 110 of the first heat exchanger 100 according to Modification G.

[0053] Fig.16 This is an enlarged view of the upper end portion and the periphery of the first heat transfer plate 110 of the first heat exchanger 100 according to another example of Modification G.

[0054] Fig.17 1 is a schematic diagram showing the structure of a hot water supply device 2 including a first heat exchanger 100 . DETAILED DESCRIPTION

[0055] <First embodiment>

[0056] (1) Refrigeration cycle device 1

[0057] First, a refrigeration cycle device 1 including a first heat exchanger 100 according to a first embodiment of the present disclosure will be described. The refrigeration cycle device 1 is a two-way refrigerant cycle device that performs cooling and heating operations of an air-conditioned space (not shown) such as a room in a building by executing a vapor compression cycle.

[0058] The refrigerant cycle device 1 heats or cools water, and uses the water to perform heating operation and cooling operation of a target space (not shown). The refrigerant cycle device 1 includes a first heat exchanger 100, a second heat exchanger 300, a first fluid circuit 10, a second fluid circuit 20, a water circuit 30, and a control unit 40. The details will be described later. The first fluid circuit 10 circulates the first fluid, the second fluid circuit 20 circulates the second fluid having a lower boiling point than the first fluid, and the water circuit 30 circulates the water. Although not limited, in this embodiment, the water circuit 30 is set indoors, and the second fluid circuit 20 is set outdoors. The first fluid circuit 10 may be set either indoors or outdoors, or a part of it may be set either indoors or outdoors.

[0059] (1-1) First Heat Exchanger 100

[0060] The first heat exchanger 100 exchanges heat between the first fluid circulating in the first fluid circuit 10 and the second fluid circulating in the second fluid circuit 20. The first heat exchanger 100 includes first flow tubes 141a and 141b, second flow tubes 142a and 142b, a first flow path 220, and a second flow path 230.

[0061] The first flow path 220 is a flow path for a first fluid to flow. The first flow path 220 is provided between the first flow tube 1410a and the first flow tube 141b. The second flow path 230 is a flow path for a second fluid to flow. The second flow path 230 is formed between the second flow tube 142a and the second flow tube 142b. Heat exchange is performed between the first fluid flowing in the first flow path 220 and the second fluid passing through the second flow path 230. The detailed structure of the first heat exchanger 100 will be described later.

[0062] (1-2) Second Heat Exchanger 300

[0063] The second heat exchanger 300 exchanges heat between the first fluid circulating in the first fluid circuit 10 and the water circulating in the water circuit 30. The second heat exchanger 300 includes first flow tubes 341a and 341b, second flow tubes 342a and 342b, a first flow path 420, and a second flow path 430.

[0064] The first flow path 420 is a flow path for the first fluid to flow. The first flow path 420 is provided between the first flow pipe 341a and the first flow pipe 341b. The second flow path 430 is a flow path for water to flow. The second flow path 430 is formed between the second flow pipe 342a and the second flow pipe 342b. Heat exchange is performed between the first fluid flowing in the first flow path 420 and the water passing through the second flow path 430.

[0065] (1-3) First Fluid Circuit 10

[0066] In the first fluid circuit 10, the first fluid is heated or cooled. The first fluid circuit 10 is composed of a compressor 11, a four-way switching valve 12, an expansion valve 13, a first flow path 220 of a first heat exchanger 100, and a first flow path 420 of a second heat exchanger 300. The compressor 11, the four-way switching valve 12, the expansion valve 13, the first flow path 220 of the first heat exchanger 100, and the first flow path 420 of the second heat exchanger 300 are connected by pipes, and the first fluid circulates inside. In this embodiment, the first fluid is R1234ze.

[0067] The compressor 11 sucks the low-pressure first fluid in the first fluid circuit 10 from the suction portion 11 a , compresses the first fluid, and discharges the fluid from the discharge portion 11 b as the high-pressure first fluid.

[0068] The four-way switching valve 12 has a first valve port 12a, a second valve port 12b, a third valve port 12c, and a fourth valve port 12d. The four-way switching valve 12 switches between a first state and a second state in which the communication states of the first valve port 12a, the second valve port 12b, the third valve port 12c, and the fourth valve port 12d are different, based on the instruction of the control unit 40. In the first state, the first valve port 12a is connected to the second valve port 12b, and the third valve port 12c is connected to the fourth valve port 12d. In the second state, the first valve port 12a is connected to the fourth valve port 12d, and the second valve port 12b is connected to the third valve port 12c.

[0069] The first valve port 12a is connected to the discharge portion 11b of the compressor 11. The second valve port 12b is connected to the first flow pipe 341b of the second heat exchanger 300. The third valve port 12c is connected to the suction portion 11a of the compressor 11. The fourth valve port 12d is connected to the first flow pipe 141a of the first heat exchanger 100.

[0070] The expansion valve 13 functions as a pressure reducing device that adjusts the flow rate of the first fluid circulating in the first fluid circuit 10 and reduces the pressure of the first fluid.

[0071] One end of the expansion valve 13 is connected to the first flow pipe 141 b of the first heat exchanger 100 , and the other end of the expansion valve 13 is connected to the first flow pipe 341 a of the second heat exchanger 300 .

[0072] (1-4) Second Fluid Circuit 20

[0073] In the second fluid circuit 20, the second fluid is heated or cooled. The second fluid circuit 20 is composed of a compressor 21, a four-way switching valve 22, an expansion valve 23, a heat source heat exchanger 24, and a second flow path 230 of the first heat exchanger 100. The compressor 21, the four-way switching valve 22, the expansion valve 23, the heat source heat exchanger 24, and the second flow path 230 of the first heat exchanger 100 are connected by pipes, and the second fluid circulates inside. In this embodiment, the second fluid is carbon dioxide.

[0074] The compressor 21 sucks the low-pressure second fluid in the second fluid circuit 20 from the suction portion 21 a , compresses the second fluid, and discharges the low-pressure second fluid from the discharge portion 21 b .

[0075] The four-way switching valve 22 has a first valve port 22a, a second valve port 22b, a third valve port 22c, and a fourth valve port 22d. The four-way switching valve 22 switches between a first state and a second state in which the communication states of the first valve port 22a, the second valve port 22b, the third valve port 22c, and the fourth valve port 22d are different, based on the instruction of the control unit 40. In the first state, the first valve port 22a is connected to the second valve port 22b, and the third valve port 22c is connected to the fourth valve port 22d. In the second state, the first valve port 22a is connected to the fourth valve port 22d, and the second valve port 22b is connected to the third valve port 22c.

[0076] The first valve port 22a is connected to the discharge portion 21b of the compressor 21. The second valve port 22b is connected to the second flow pipe 142b of the first heat exchanger 100. The third valve port 22c is connected to the suction portion 21a of the compressor 21. The fourth valve port 22d is connected to one end of the heat source heat exchanger 24.

[0077] The expansion valve 23 functions as a decompression device that adjusts the flow rate of the second fluid circulating in the second fluid circuit 20 and decompresses the second fluid.

[0078] One end of the expansion valve 23 is connected to the second flow pipe 142a of the first heat exchanger 100. The other end of the expansion valve 23 is connected to the other end of the heat source heat exchanger 24.

[0079] The heat source heat exchanger 24 exchanges heat between the second fluid circulating in the second fluid circuit 20 and a heat source (for example, outdoor air).

[0080] (1-5) Water circuit 30

[0081] Water that exchanges heat with the first fluid circulates in the water circuit 30. The water circuit 30 is composed of a water circulation pump 31, a water storage tank 32, and a second flow path 430 of the second heat exchanger 300. The water circulation pump 31, the water storage tank 32, and the second flow path 430 of the second heat exchanger 300 are connected by piping, and water circulates inside.

[0082] The water circulation pump 31 circulates water inside the water circuit 30. The water circulation pump 31 sucks water inside the water circuit 30 from the suction part 31a, and discharges it from the discharge part 31b.

[0083] The suction portion 31 a is connected to the second flow pipe 342 b of the second heat exchanger 300 .

[0084] The water storage tank 32 stores water heated or cooled by the second heat exchanger 300, thereby heating or cooling the indoor air (in other words, heating or cooling). The water storage tank 32 has a water intake portion 32a for taking in water circulating in the water circuit 30 and a drainage portion 32b for discharging the stored water.

[0085] The water intake portion 32a is connected to the discharge portion 31b of the water circulation pump 31. The water discharge portion 32b is connected to the second flow pipe 342b of the second heat exchanger 300.

[0086] (1-6) Control Unit 40

[0087] The control unit 40 controls the compressors 11, 21, the four-way switching valves 12, 22, the expansion valves 13, 23, and the water circulation pump 31. Although not shown in the figure, the control unit 40 is electrically connected to the compressors 11, 21, the four-way switching valves 12, 22, the expansion valves 13, 23, and the water circulation pump 31 so as to be able to send and receive control signals.

[0088] (1-7) Operation of Refrigeration Cycle Device 1

[0089] The refrigeration cycle device 1 performs a heating operation and a cooling operation.

[0090] (1-7-1) Heating Operation

[0091] The heating operation is an operation in which the refrigerant cycle device 1 heats water in the water circuit 30. In the heating operation, the controller 40 sets the four-way switching valves 12 and 22 to the first state, drives the compressors 11 and 21 and the water circulation pump 31, and controls the openings of the expansion valves 13 and 23.

[0092] (1-7-1-1) Second Fluid Circuit 20

[0093] The compressor 21 sucks the second fluid in the low-pressure gas phase in the second fluid circuit 20 from the suction part 21a, and discharges it from the discharge part 21b as the second fluid in the high-pressure gas phase. The second fluid in the high-pressure gas phase passes through the four-way switching valve 22 in the order of the first valve port 22a and the second valve port 22b, and reaches the second flow path 230 from the second flow pipe 142a of the first heat exchanger 100. In the second flow path 230 of the first heat exchanger 100, the second fluid in the high-pressure gas phase is condensed to become the second fluid in the high-pressure liquid phase. At this time, the second fluid releases heat to the first fluid passing through the first flow path 220. The second fluid in the high-pressure liquid phase reaches the expansion valve 23. The expansion valve 23 set to an appropriate opening decompresses the second fluid in the high-pressure liquid phase to become the second fluid in the low-pressure gas-liquid two-phase. The second fluid in the low-pressure gas-liquid two-phase evaporates in the heat source heat exchanger 24 to become the second fluid in the low-pressure gas phase. At this time, the second fluid absorbs heat from the heat source. The second fluid in the low-pressure gas phase passes through the four-way switching valve 22 in the order of the fourth valve port 22d and the third valve port 22c, and is then sucked into the compressor 21 from the suction portion 21a.

[0094] (1-7-1-2) First Fluid Circuit 10

[0095] The compressor 11 sucks the low-pressure gas phase first fluid in the first fluid circuit 10 from the suction part 11a, and discharges it from the discharge part 11b as the high-pressure gas phase first fluid. The high-pressure gas phase first fluid passes through the four-way switching valve 12 in the order of the first valve port 12a and the second valve port 12b, and reaches the first flow path 420 from the first flow pipe 341a of the second heat exchanger 300. In the first flow path 420 of the second heat exchanger 300, the high-pressure gas phase first fluid is condensed to become the high-pressure liquid phase first fluid. At this time, the first fluid releases heat to the water passing through the second flow path 430. The high-pressure liquid phase first fluid reaches the expansion valve 13. The expansion valve 13 set to an appropriate opening reduces the pressure of the high-pressure liquid phase first fluid to become the low-pressure gas-liquid two-phase first fluid. After the low-pressure gas-liquid two-phase first fluid passes through the first flow pipe 141a of the first heat exchanger 100, it evaporates in the first flow path 220 to become the low-pressure gas phase first fluid. At this time, the first fluid absorbs heat from the second fluid passing through the second flow path 230. The first fluid in the low-pressure gas phase passes through the four-way switching valve 12 in the order of the fourth valve port 12d and the third valve port 12c, and is then sucked into the compressor 11 from the suction portion 11a.

[0096] (1-7-1-3) Water circuit 30

[0097] The water circulation pump 31 sucks water circulating in the water circuit 30 from the suction part 31a and discharges it from the discharge part 31b. The discharged water is stored in the water storage tank 32 through the water intake part 32a. The water stored in the water storage tank 32 releases heat to the indoor air. In other words, the water stored in the water storage tank 32 heats the indoor air. After the water stored in the water storage tank 32 passes through the discharge part 32b, it reaches the second flow path 430 through the second flow pipe 342a of the second heat exchanger 300. The water reaching the second flow path 430 of the second heat exchanger 300 absorbs heat from the first fluid passing through the first flow path 420. The water that absorbs heat is sucked into the water circulation pump 31 from the suction part 31a.

[0098] (1-7-2) Refrigeration operation

[0099] The cooling operation is an operation in which the refrigerant cycle device 1 cools water in the water circuit 30. In the cooling operation, the controller 40 sets the four-way switching valves 12 and 22 to the second state, drives the compressors 11 and 21 and the water circulation pump 31, and controls the openings of the expansion valves 13 and 23.

[0100] (1-7-2-1) Second Fluid Circuit 20

[0101] The compressor 21 sucks the second fluid in the low-pressure gas phase in the second fluid circuit 20 from the suction part 21a, and discharges it from the discharge part 21b as the second fluid in the high-pressure gas phase. The second fluid in the high-pressure gas phase passes through the four-way switching valve 22 in the order of the first valve port 22a and the fourth valve port 22d to reach the heat source heat exchanger 24. In the heat source heat exchanger 24, the second fluid in the high-pressure gas phase is condensed to become the second fluid in the high-pressure liquid phase. At this time, the second fluid releases heat to the heat source. The second fluid in the high-pressure liquid phase reaches the expansion valve 23. The expansion valve 23 set to an appropriate opening decompresses the second fluid in the high-pressure liquid phase to become the second fluid in the low-pressure gas-liquid two-phase. After the second fluid in the low-pressure gas-liquid two-phase passes through the second flow pipe 142b of the first heat exchanger 100, it evaporates in the second flow path 230 to become the second fluid in the low-pressure gas phase. At this time, the second fluid absorbs heat from the first fluid passing through the second flow path 230. The second fluid in the low-pressure gas phase passes through the four-way switching valve 22 in the order of the second valve port 22b and the third valve port 22c, and is then sucked into the compressor 21 from the suction portion 21a.

[0102] (1-7-2-2) First Fluid Circuit 10

[0103] The compressor 11 sucks the low-pressure gas phase first fluid in the first fluid circuit 10 from the suction part 11a, and discharges it from the discharge part 11b as the high-pressure gas phase first fluid. The high-pressure gas phase first fluid passes through the four-way switching valve 12 in the order of the first valve port 12a and the fourth valve port 12d, and reaches the first flow path 220 from the first flow pipe 141b of the first heat exchanger 100. In the first flow path 220 of the first heat exchanger 100, the high-pressure gas phase first fluid condenses to become the high-pressure liquid phase first fluid. At this time, the first fluid releases heat to the second fluid passing through the second flow path 230. The high-pressure liquid phase first fluid reaches the expansion valve 13. The expansion valve 13 set to an appropriate opening reduces the pressure of the high-pressure liquid phase first fluid to become the low-pressure gas-liquid two-phase first fluid. After the low-pressure gas-liquid two-phase first fluid passes through the first flow pipe 341b of the second heat exchanger 300, it evaporates in the first flow path 420 to become the low-pressure gas phase first fluid. At this time, the first fluid absorbs heat from the second fluid passing through the second flow path 430. The first fluid in the low-pressure gas phase passes through the four-way switching valve 12 in the order of the second valve port 12 b and the third valve port 12 c , and is then sucked into the compressor 11 from the suction portion 11 a .

[0104] (1-7-2-3) Water circuit 30

[0105] The water circulation pump 31 sucks water circulating in the water circuit 30 from the suction part 31a and discharges it from the discharge part 31b. The discharged water is stored in the water storage tank 32 through the water intake part 32a. The water stored in the water storage tank 32 absorbs heat from the indoor air. In other words, the water stored in the water storage tank 32 cools the indoor air. After the water stored in the water storage tank 32 passes through the discharge part 32b, it passes through the second flow pipe 342a of the second heat exchanger 300 and reaches the second flow path 430. The water reaching the second flow path 430 of the second heat exchanger 300 releases heat to the first fluid passing through the first flow path 420. The water that has released heat is sucked into the water circulation pump 31 from the suction part 31a.

[0106] (2) Heat exchanger

[0107] (2-1) Overall structure

[0108] The first heat exchanger 100 is a plate-type heat exchanger including a plurality of first heat transfer plates 110, a plurality of second heat transfer plates 120, a plurality of partition walls 130, a first frame 140, and a second frame 150. The first heat exchanger 100 has a first flow path 220 and a second flow path 230 disposed therein.

[0109] The first heat transfer plate 110, the second heat transfer plate 120 and the partition wall 130 are metal plate-shaped members having the same rectangular shape. Figure 2As shown, the outer shapes of the first heat transfer plate 110, the second heat transfer plate 120, the partition wall 130, the first frame 140, and the second frame 150 are formed in a strip shape that is long in the first direction.

[0110] The plurality of first heat transfer plates 110 and the plurality of second heat transfer plates 120 are alternately stacked between the first frame 140 and the second frame 150 with the partition walls 130 interposed therebetween. The number of the plurality of first heat transfer plates 110 and the plurality of second heat transfer plates 120 is not particularly limited and is appropriately set according to the required performance. The first frame 140, the first heat transfer plates 110, the partition walls 130, the second heat transfer plates 120 and the second frame 150 are not limited and are integrally joined, for example, by brazing.

[0111] In the following description, for convenience, the first direction is sometimes referred to as the length direction DL. Also, the width direction of the first heat transfer plate 110, the partition wall 130, and the second heat transfer plate 120 is sometimes referred to as the width direction DW. Also, the thickness direction (in other words, the stacking direction) of the first heat transfer plate 110, the partition wall 130, and the second heat transfer plate 120 is sometimes referred to as the thickness direction DT (all refer to the arrows shown in some figures). Also, the upper and lower directions mentioned in the following description correspond to "up" and "down" shown in some figures.

[0112] (2-2) Detailed structure

[0113] (2-2-1) First heat transfer plate 110

[0114] The first heat transfer plate 110 and the adjacently stacked partition walls 130 form a first flow path 220. The first heat transfer plate 110 has first flow ports 111a and 111b, first through holes 112a and 112b, a first heat transfer region 113, and a plurality of first connection portions 115a and 115b.

[0115] The first flow openings 111a and 111b are holes for introducing or discharging the first fluid into the first flow path 220. The first flow openings 111a and 111b are formed to penetrate the first heat transfer plate 110 along the thickness direction DT. In the present embodiment, the first flow openings 111a and 111b are formed in a circular shape when the first heat transfer plate 110 is viewed from above. The first flow openings 111a and 111b are formed at positions away from both ends of the first heat transfer region 113 along the length direction DL by a predetermined distance in a manner such that the center is located at the center in the width direction DW. The first flow opening 111a is formed above the first heat transfer region 113, and the first flow opening 111b is formed below the first heat transfer region 113.

[0116] The first through holes 112a and 112b are holes for the second fluid to pass through along the thickness direction DT. The first through holes 112a and 112b are formed to penetrate the first heat transfer plate 110 along the thickness direction DT. In the present embodiment, when the first heat transfer plate 110 is viewed from above, the first through holes 112a and 112b are formed in a circular shape. The first through holes 112a and 112b are formed at a position away from the first flow openings 111a and 111b along the length direction DL by a predetermined distance toward the end of the first heat transfer plate 110 in the length direction DL in such a manner that the center is located at the center in the width direction DW. In other words, the first through holes 112a and 112b are formed in the length direction DL at a position opposite to the first heat transfer region 113 across the first flow openings 111a and 111b. The first through hole 112a is formed above the first flow opening 111a, and the first through hole 112b is formed below the first flow opening 111b.

[0117] The first heat transfer region 113 is a region through which the first fluid flowing in from the first flow ports 111a and 111b exchanges heat with the second fluid while passing through. The first heat transfer region 113 is a rectangular region having substantially the same width as the first heat transfer plate 110. The first heat transfer region 113 is formed from the center of the first heat transfer plate 110 in the longitudinal direction DL toward both ends to the ends of the first connection portions 115a and 115b on the first heat transfer region 113 side.

[0118] The first heat transfer region 113 is formed with a plurality of first heat transfer channels 114, which are groove-shaped channels through which the first fluid flowing in from the first flow ports 111a and 111b passes. The first heat transfer channels 114 are grooves formed along the length direction DL. The plurality of first heat transfer channels 114 are formed at predetermined intervals along the width direction DW of the first heat transfer plate 110.

[0119] The first connection portion 115a is a groove-shaped flow path having one end connected to the first flow port 111a and the other end connected to the upper end portion in the length direction DL of the first heat transfer region 113. The first connection portion 115b is a groove-shaped flow path having one end connected to the first flow port 111b and the other end connected to the lower end portion in the length direction DL of the first heat transfer region 113. Adjacent first connection portions 115a are separated from each other by first separation portions 116a. Adjacent first connection portions 115b are separated from each other by first separation portions 116b.

[0120] The first flow path 220 is composed of the first heat transfer region 113 (first heat transfer flow path 114) and first connection portions 115a and 115b connecting both ends of the first heat transfer region 113. Therefore, the first heat exchanger 100 has the same number of first flow paths 220 as the number of first heat transfer plates 110.

[0121] In this embodiment, if Figure 4 As shown, the first connection parts 115a and 115b are formed in a straight line. The first connection parts 115a and 115b are formed so that the flow path cross-sectional area increases from the first flow openings 111a and 111b toward the first heat transfer region 113. Although not limited, in this embodiment, eighteen first connection parts 115a and 115b are connected to one first flow opening 111a and 111b.

[0122] The first connection parts 115a and 115b can also be formed so that in a cross section orthogonal to the flow direction of the first fluid, the first separation parts 116a and 116b that separate the adjacent first connection parts 115a and 115b from each other satisfy the following relationship (Formula 1), preferably satisfy the following relationship (Formula 2).

[0123] 0.005<La1 / P1<0.15···(Formula 1)

[0124] 0.005<La1 / P1<0.05···(Formula 2)

[0125] like Figure 5 As shown, La1 is the length of the first separation parts 116a and 116b in contact with the partition wall 130. P1 is the interval between the adjacent first separation parts 116a and 116b. P1 is obtained by adding La1 to Lb1, which is the length of the contact between the partition wall 130 and the first connection parts 115a and 115b (P1=Lb1+La1).

[0126] The first heat transfer region 113 (first heat transfer channel 114) and the first connecting parts 115a and 115b are formed on one surface of the first heat transfer plate 110. The first flow ports 111a and 111b, the first through holes 112a and 112b, the first heat transfer region 113, and the first connecting parts 115a and 115b are not limited and are formed by, for example, press working.

[0127] (2-2-2) Second heat transfer plate 120

[0128] The second heat transfer plate 120 forms a second flow path 230 together with the adjacently stacked partition walls 130. The second heat transfer plate 120 has second flow ports 121a and 121b, second through holes 122a and 122b, a second heat transfer region 123, a plurality of second connection portions 125a and 125b, and second protrusions 127a and 127b.

[0129] The second flow openings 121a and 121b are holes for introducing or discharging the second fluid into the second flow path 111. The second flow openings 121a and 121b are formed to penetrate the second heat transfer plate 120 along the thickness direction DT. In the present embodiment, the second flow openings 121a and 121b are formed in a circular shape when the second heat transfer plate 120 is viewed from above. The second flow openings 121a and 121b are formed at a position away from the second through holes 122a and 122b along the length direction DL toward the end of the second heat transfer plate 120 in the length direction DL in such a manner that the center is located at the center in the width direction DW. In other words, the second flow openings 121a and 121b are formed at a position opposite to the second heat transfer region 123 across the second through holes 122a and 122b. The second flow opening 121a is formed below the second heat transfer region 123, and the second flow opening 121b is formed above the second heat transfer region 123.

[0130] The second flow opening 121a has the same shape as the first through hole 112a and is formed at a position that overlaps when viewed from above when the first heat transfer plate 110 and the second heat transfer plate 120 are stacked. The second flow opening 121b has the same shape as the first through hole 112b and is formed at a position that overlaps when viewed from above when the first heat transfer plate 110 and the second heat transfer plate 120 are stacked.

[0131] The second through holes 122a and 122b are holes for the second fluid to pass through in the thickness direction. The second through holes 122a and 122b are formed to penetrate the second heat transfer plate 120 in the thickness direction. In the present embodiment, when the second heat transfer plate 120 is viewed from above, the second through holes 122a and 122b are formed in a circular shape. The second through holes 122a and 122b are formed at a position away from both ends of the second heat transfer region 123 in the length direction DL by a predetermined distance in the length direction DL so that the center is located in the center in the width direction DW. The second through hole 122a is formed below the second flow port 121a, and the second through hole 122b is formed above the second flow port 121b.

[0132] The second through hole 122a and the first flow opening 111a have the same shape and are formed at such a position that they overlap when viewed from above when the first heat transfer plate 110 and the second heat transfer plate 120 are stacked. The second through hole 122b and the first flow opening 111b have the same shape and are formed at such a position that they overlap when viewed from above when the first heat transfer plate 110 and the second heat transfer plate 120 are stacked.

[0133] The second heat transfer region 123 is a region through which the second fluid flowing in from the second flow ports 121a and 121b passes while exchanging heat with the first fluid. The second heat transfer region 123 is a rectangular region having substantially the same width as the second heat transfer plate 120. The second heat transfer region 123 is formed from the center of the second heat transfer plate 120 in the longitudinal direction DL toward both ends to the end portions of the second connection portions 125a and 125b on the second heat transfer region 123 side.

[0134] The second heat transfer region 123 is formed with a plurality of second heat transfer channels 124, which are groove-shaped channels through which the second fluid flowing in from the second flow ports 121a and 121b passes. The second heat transfer channels 124 are grooves formed along the length direction DL. The plurality of second heat transfer channels 124 are formed at predetermined intervals along the width direction DW of the second heat transfer plate 120.

[0135] The second heat transfer region 123 has the same shape as the first heat transfer region 113 and is formed at a position that overlaps when viewed from above when the first heat transfer plate 110 and the second heat transfer plate 120 are stacked. The plurality of second heat transfer channels 124 has the same shape as the plurality of first heat transfer channels 114 and is formed at a position that overlaps when viewed from above when the first heat transfer plate 110 and the second heat transfer plate 120 are stacked.

[0136] The second connection portion 125a is a groove-shaped flow path having one end connected to the second flow port 121a and the other end connected to the lower end of the second heat transfer region 123 in the longitudinal direction DL. The second connection portion 125b is a groove-shaped flow path having one end connected to the second flow port 121b and the other end connected to the upper end of the second heat transfer region 123 in the longitudinal direction DL. The second connection portions 125a and 125b are formed so as to bypass the outer sides of the second through holes 122a and 122b from the second flow ports 121a and 121b toward the second heat transfer region 123. Adjacent second connection portions 125a are separated from each other by second separation portions 126a. Adjacent second connection portions 125b are separated from each other by second separation portions 126b.

[0137] The second flow path 230 is composed of the second heat transfer region 123 (second heat transfer flow path 124) and second connection portions 125a and 125b connected to both ends of the second heat transfer region 123. Therefore, the first heat exchanger 100 has the same number of second flow paths 230 as the number of second heat transfer plates 120.

[0138] In this embodiment, if Figure 7As shown in FIG. 1 , the second connection parts 125a and 125b are formed in a curved shape. The second connection parts 125a and 125b are formed so that the flow path cross-sectional area increases from the second flow openings 121a and 121b toward the second heat transfer region 123. Although not limited, in this embodiment, twelve second connection parts 125a and 125b are connected to one first flow opening 111a and 111b. In more detail, as shown in FIG. Figure 6 , Figure 7 As shown, the second connection parts 125a and 125b connected to one first flow port 111a and 111b are formed so as to be divided into two branches in the width direction DW into six and bypass the outside of the second through holes 122a and 122b.

[0139] The second protrusions 127a and 127b are provided on the second connection parts 125a and 125b. The second protrusions 127a and 127b divide the second connection parts 125a and 125b, and limit the force (pressure) received by the partition wall 130 from the second fluid. The second protrusion 127a is formed in a linear shape protruding from the second heat transfer area 123 toward the second connection part 125a by a predetermined length when viewed from above. The second protrusion 127b is formed in a linear shape protruding from the second heat transfer area 123 toward the second connection part 125b by a predetermined length when viewed from above. In the present embodiment, although not limited, the second protrusions 127a and 127b are formed as four second connection parts located on the inner side of the six second connection parts 125a and 125b divided into two branches.

[0140] Multiple second connection parts 125a, 125b can also be formed as second separation parts 126a, 126b or second protrusions 127a, 127b that separate adjacent second connection parts 125a, 125b from each other in a cross section orthogonal to the flow direction of the second fluid, satisfying the following relationship (Formula 3), preferably satisfying the following relationship (Formula 4).

[0141] 0.005<La2 / P2<0.15···(Formula 3)

[0142] 0.02<La2 / P2<0.05···(Formula 4)

[0143] like Figure 8 As shown in FIG. 1 , La2 is the length of the second separation portion 126a, 126b or the second protrusion 127a, 127b joined to the partition wall 130. P2 is the interval between the adjacent second separation portions 126a, 126b or the second protrusion 127a, 127b. P2 is obtained by adding La2 (P2 = Lb2, the length of the contact between the partition wall 130 and the first connection portion 115a, 115b) to

[0144] Lb1+Lb2) and find it.

[0145] The second heat transfer region 123 (second heat transfer channel 124) and the second connection parts 125a and 125b are formed on one surface of the second heat transfer plate 120. The second flow ports 121a and 121b, the second through holes 122a and 122b, the second heat transfer region 123, the second connection parts 125a and 125b, and the second protrusions 127a and 127b are not limited and are formed by, for example, stamping.

[0146] (2-2-3) Next door 130

[0147] The partition wall 130 is a flat plate that partitions the first heat transfer plate 110 and the second heat transfer plate 120 in the thickness direction DT. The partition wall 130 has two first flow holes 131a and 131b and two second flow holes 132a and 132b.

[0148] The first flow holes 131a and 131b are holes through which the first fluid passes in the thickness direction DT. The first flow holes 131a and 131b are formed to penetrate the partition wall 130 in the thickness direction DT. In the present embodiment, the first flow holes 131a and 131b are formed in a circular shape when the partition wall 130 is viewed in a plan view.

[0149] The first flow hole 131a has the same shape as the first flow port 111a and the second through hole 122b, and is formed at a position that overlaps when viewed from above when the partition wall 130, the first heat transfer plate 110, and the second heat transfer plate 120 are stacked. The first flow hole 131b has the same shape as the first flow port 111b and the second through hole 122a, and is formed at a position that overlaps when viewed from above when the partition wall 130, the first heat transfer plate 110, and the second heat transfer plate 120 are stacked.

[0150] The second flow holes 132a and 132b are holes through which the second fluid passes in the thickness direction. The second flow holes 132a and 132b are formed to penetrate the partition wall 130 in the thickness direction. In the present embodiment, the second flow holes 132a and 132b are formed in a circular shape when the partition wall 130 is viewed from above.

[0151] The second flow hole 132a has the same shape as the second flow port 121b and the first through hole 112a, and is formed at a position that overlaps when viewed from above when the partition wall 130 is stacked with the first heat transfer plate 110 and the second heat transfer plate 120. The second flow hole 132b has the same shape as the second flow port 121a and the first through hole 112b, and is formed at a position that overlaps when viewed from above when the partition wall 130 is stacked with the first heat transfer plate 110 and the second heat transfer plate 120.

[0152] (2-2-4) First Communication Paths 211a, 211b and Second Communication Paths 212a, 212b

[0153] The first flow holes 131a, the first flow ports 111a, and the second through holes 122b are interconnected by stacking the plurality of first heat transfer plates 110, the plurality of second heat transfer plates 120, and the plurality of partition walls 130. The interconnected first flow holes 131a, the first flow ports 111a, and the second through holes 122b constitute a first communication path 211a extending along the thickness direction DT.

[0154] The first communication passage 211 a communicates with the first flow passage 220 via the first flow port 111 a .

[0155] The first flow holes 131b, the first flow ports 111b, and the second through holes 122a are interconnected by stacking the plurality of first heat transfer plates 110, the plurality of second heat transfer plates 120, and the plurality of partition walls 130. The interconnected first flow holes 131b, the first flow ports 111b, and the second through holes 122a constitute a first communication path 211b extending along the thickness direction DT.

[0156] The first communication passage 211 b communicates with the first flow passage 220 via the first flow port 111 b .

[0157] The second flow holes 132b, the second flow ports 121a, and the first through holes 112b are interconnected by stacking the plurality of first heat transfer plates 110, the plurality of second heat transfer plates 120, and the plurality of partition walls 130. The interconnected second flow holes 132b, the second flow ports 121a, and the first through holes 112b constitute a second communication path 212a extending along the thickness direction DT.

[0158] The second communication passage 212a communicates with the second flow passage 230 via the second flow port 121a.

[0159] The second flow holes 132a, the second flow ports 121b, and the first through holes 112a are interconnected by stacking the plurality of first heat transfer plates 110, the plurality of second heat transfer plates 120, and the plurality of partition walls 130. The interconnected second flow holes 132a, the second flow ports 121b, and the first through holes 112a constitute a second communication path 212b extending along the thickness direction DT.

[0160] The second communication passage 212 b communicates with the second flow passage 230 via the second flow port 121 b .

[0161] (2-2-5) First Frame 140 and Second Frame 150

[0162] The first frame 140 and the second frame 150 are metal plate-shaped members that sandwich a plurality of first heat transfer plates 110 and a plurality of second heat transfer plates 120 alternately stacked with the partition walls 130 between both ends in the thickness direction DT.

[0163] The first frame 140 has a first flow tube 141 a , a first flow tube 141 b , a second flow tube 142 a , and a second flow tube 142 b .

[0164] The first flow pipe 141 a passes through the first frame 140 and communicates with the first communication passage 211 a .

[0165] The first flow pipe 141 b passes through the first frame 140 and communicates with the first communication passage 211 b .

[0166] The second flow pipe 142 a passes through the first frame 140 and communicates with the second communication passage 212 a .

[0167] The second flow pipe 142 b passes through the first frame 140 and communicates with the second communication passage 212 b .

[0168] (2-3) Flow of the First Fluid and the Second Fluid

[0169] (2-3-1) Heating operation

[0170] The low-pressure gas-liquid two-phase first fluid introduced from the first flow pipe 141a of the first heat exchanger 100 passes through the first connecting passage 211a and flows into the first flow passage 220 from the first flow port 111a. The gas-liquid two-phase first fluid flowing into the first flow passage 220 passes through the first connection portion 115a, the first heat transfer region 113 (the first heat transfer flow passage 114), and the first connection portion 115b in sequence. The first fluid flowing in the first heat transfer region 113 exchanges heat with the second fluid of the adjacent second flow passage 230 via the partition wall 130 and evaporates, absorbing heat from the second fluid. In other words, the first heat exchanger 100 functions as an evaporator of the first fluid. The evaporated first fluid becomes a low-pressure gas-phase first fluid, which is discharged from the first flow pipe 141b through the first flow port 111b and the first connecting passage 211b.

[0171] On the other hand, the second fluid in the high-pressure gas phase introduced from the second flow pipe 142a of the first heat exchanger 100 passes through the second connecting passage 212a and flows into the second flow passage 230 from the second flow port 121a. The second fluid in the high-pressure gas phase that flows into the second flow passage 230 passes through the second connection portion 125a, the second heat transfer region 123 (the second heat transfer flow passage 124), and the second connection portion 125b in sequence. The second fluid flowing in the second heat transfer region 123 exchanges heat with the first fluid in the adjacent first flow passage 220 via the partition wall 130 to condense and release heat. In other words, the first heat exchanger 100 functions as a condenser of the second fluid. The condensed second fluid becomes a second fluid in the high-pressure liquid phase, which is discharged from the second flow pipe 142b through the second flow port 121b and the second connecting passage 212b.

[0172] (2-3-2) Refrigeration operation

[0173] The first fluid in the high-pressure gas phase introduced from the first flow pipe 141b of the first heat exchanger 100 passes through the first connecting passage 211b and flows into the first flow passage 220 from the first flow port 111b. The first fluid in the high-pressure gas phase that flows into the first flow passage 220 passes through the first connection portion 115b, the first heat transfer region 113 (the first heat transfer flow passage 114), and the first connection portion 115a in sequence. The first fluid flowing in the first heat transfer region 113 exchanges heat with the second fluid in the adjacent second flow passage 230 via the partition wall 130 and condenses, releasing heat to the second fluid. In other words, the first heat exchanger 100 functions as a heat radiator for the first fluid. The condensed first fluid becomes the first fluid in the high-pressure liquid phase, and is discharged from the first flow pipe 141a through the first flow port 111a and the first connecting passage 211a.

[0174] On the other hand, the low-pressure gas-liquid two-phase second fluid introduced from the second flow pipe 142b of the first heat exchanger 100 passes through the second connecting passage 212b and flows into the second flow passage 230 from the second flow port 121b. The low-pressure gas-liquid two-phase second fluid flowing into the second flow passage 230 passes through the second connection portion 125b, the second heat transfer region 123 (the second heat transfer flow passage 124), and the second connection portion 125a in sequence. The second fluid flowing in the second heat transfer region 123 exchanges heat with the first fluid of the adjacent first flow passage 220 via the partition wall 130 and evaporates, absorbing heat from the first fluid. In other words, the first heat exchanger 100 functions as an evaporator of the second fluid. The evaporated second fluid becomes a low-pressure gas-phase second fluid, which is discharged from the second flow pipe 142a through the second flow port 121a and the second connecting passage 212a.

[0175] (3) Features

[0176] (3-1)

[0177] The first heat exchanger 100 includes a first heat transfer plate 110 and a second heat transfer plate 120 which are stacked on each other.

[0178] The first heat transfer plate 110 has first flow ports 111 a and 111 b , first through holes 112 a and 112 b , a first heat transfer region 113 , and first connection portions 115 a and 115 b .

[0179] The first flow ports 111a and 111b are used to introduce or export the first fluid. The first through holes 112a and 112b allow the second fluid with a lower boiling point than the first fluid to pass through in the thickness direction. The first heat transfer region 113 is a region where the first fluid flowing in from the first flow ports 111a and 111b passes through while exchanging heat with the second fluid. One end of the first connection portion 115a and 115b is connected to the first flow ports 111a and 111b, and the other end is connected to the first heat transfer region 113.

[0180] The second heat transfer plate 120 has second flow ports 121 a and 121 b , second through holes 122 a and 122 b , a second heat transfer region 123 , and second connection portions 125 a and 125 b .

[0181] The second flow ports 121a and 121b are connected to the first through holes 112a and 112b to introduce or export the second fluid. The second through holes 122a and 122b allow the first fluid to pass through in the thickness direction. The second heat transfer region 123 is a region where the second fluid flowing in from the second flow ports 121a and 121b passes through while exchanging heat with the first fluid. One end of the second connection portion 125a and 125b is connected to the second flow ports 121a and 121b, and the other end is connected to the second heat transfer region 123.

[0182] The second flow ports 121a and 121b are formed at positions opposite to the second heat transfer region 123 across the second through holes 122a and 122b. The second connection portions 125a and 125b are formed to bypass the second through holes 122a and 122b and are provided with second protrusions 127a and 127b.

[0183] In a heat exchanger with two heat transfer plates, if the length of the flow path for the first fluid to flow is the same as the length of the flow path for the second fluid to flow, the same degree of pressure loss occurs in the two fluids. When the pressure reduction ratio caused by the pressure loss generated in this way is compared, the pressure of the fluid with the lower pressure when it flows into the two fluids decreases at a greater ratio. As a result, there is a problem that the heat exchanger cannot fully exert its heat exchange performance.

[0184] In the first heat exchanger 100, the second connection parts 125a, 125b are formed in a manner of bypassing the outside of the second through holes 122a, 122b. In other words, the length of the flow path of the first connection parts 115a, 115b for the first fluid to pass through is formed to be shorter than the length of the flow path of the second connection parts 125a, 125b for the second fluid having a lower boiling point than the first fluid to pass through. Therefore, the pressure loss generated in the first fluid when passing through the first connection parts 115a, 115b can be made less than the pressure loss generated in the second fluid when passing through the second connection parts 125a, 125b. Thus, the pressure of the first fluid is suppressed from decreasing at a larger ratio. Therefore, according to the first heat exchanger 100, even if there is a difference in pressure when the two fluids flow in, the heat exchange performance can be ensured.

[0185] (3-2)

[0186] The second protrusions 127a and 127b are linear in plan view.

[0187] (3-3)

[0188] The second connection portions 125a and 125b are linear in plan view.

[0189] (3-4)

[0190] The first connection portions 115 a and 115 b are formed such that the flow path cross-sectional area increases from the first flow ports 111 a and 111 b toward the first heat transfer region 113 .

[0191] As a result, the pressure loss of the first fluid passing through the first connection parts 115a and 115b is further reduced, thereby further suppressing the pressure of the first fluid from decreasing at a large rate. Therefore, the first heat exchanger 100 can more effectively ensure the heat exchange performance.

[0192] (3-5)

[0193] The first heat exchanger 100 includes a partition wall 130. The partition wall 130 is a plate-shaped member stacked between the first heat transfer plate 110 and the second heat transfer plate 120. The first connecting portions 115a and 115b are formed so that, in a cross section perpendicular to the flow direction of the first fluid, the first separating portions 116a and 116b that separate the adjacent first connecting portions 115a and 115b from each other are in contact with the partition wall 130 by a length La1 and the interval between the adjacent first separating portions is P1,

[0194] The relationship is 0.005<La1 / P1<0.15.

[0195] By forming the first connection portions 115a and 115b so as to satisfy the above relationship, the force (pressure) received by the partition wall 130 from the first fluid passing through the first connection portions 115a and 115b is limited, thereby preventing the pressure resistance from exceeding the limit.

[0196] (3-6)

[0197] Furthermore, the first connection portions 115 a and 115 b are formed to satisfy the relationship of 0.005<La1 / P1<0.05.

[0198] By forming the first connection portions 115a and 115b so as to satisfy the above relationship, the force (pressure) received by the partition wall 130 from the first fluid passing through the first connection portions 115a and 115b is limited, thereby preventing the pressure resistance from exceeding the limit.

[0199] (3-7)

[0200] The second connecting portions 125a, 125b are formed so that, in a cross section orthogonal to the flow direction of the second fluid, when the length of the second separation portions 126a, 126b or second protrusions 127a, 127b that separate adjacent second connecting portions 125a, 125b from each other in contact with the partition wall 130 is La2 and the interval between adjacent second separation portions 126a, 126b or second protrusions 127a, 127b is P2, the relationship 0.005<L2 / P2<0.15 is satisfied.

[0201] By forming the second connection parts 125a and 125b so as to satisfy the above relationship, the force (pressure) received by the partition wall 130 from the second fluid passing through the second connection parts 125a and 125b is limited, and the pressure resistance strength is suppressed from exceeding.

[0202] (3-8)

[0203] Furthermore, the second connection portions 125 a and 125 b are formed to satisfy the relationship of 0.02<L2 / P2<0.15.

[0204] By forming the second connection parts 125a and 125b so as to satisfy the above relationship, the force (pressure) received by the partition wall 130 from the second fluid passing through the second connection parts 125a and 125b is limited, and the pressure resistance strength is suppressed from exceeding.

[0205] (4) Modification

[0206] (4-1) Modification A

[0207] The second connection portions 125a and 125b are not limited to the above-described configuration as long as they are formed so as to bypass the outsides of the second through holes 122a and 122b and are divided by the protrusions.

[0208] like Fig. 9As shown, the second connection portion 125b of the first heat exchanger 100 of the modification A is a planar region ( Fig. 9 The second heat transfer plate 120 is provided with a plurality of second protrusions 128b that are formed into a circular shape when viewed from above. The second protrusions 128b are formed, for example, with a radius of 1 mm when viewed from above and a height of 0.5 mm in the thickness direction DT, and are arranged in the length direction DL and the width direction DW at intervals of 1 mm. The second protrusions 128b are not limited, and are formed, for example, by stamping or etching. Although not shown in the figure, the second connecting portion 125a provided below the second heat transfer plate 120 is also formed in the same shape and is provided with a plurality of second protrusions 128a.

[0209] The shape of the second protrusions 128a and 128b is not limited to a circle. The shape of the second protrusions 128a and 128b may be a triangle when viewed from above (see Fig.10 ), quadrilateral (refer to Fig.11 ), teardrop shape (refer to Fig.12 Furthermore, the shapes of the plurality of second protrusions 128a, 128b of the second connection portion 125b may be different from each other.

[0210] (4-2) Modification B

[0211] The first connection parts 115a and 115b may be formed in a curved shape.

[0212] like Fig.13 As shown in FIG. 1 , the first connection portion 115a of the first heat exchanger 100 of Modification B is formed in a curved shape. Although not shown in the figure, the first connection portion 115b provided below the first heat transfer plate 110 is also formed in the same shape.

[0213] (4-3) Modification C

[0214] In the above embodiment, R1234ze is exemplified as the first fluid, and carbon dioxide is exemplified as the second fluid, but the present invention is not limited thereto. As the first fluid, for example, R32, HFO refrigerant, a mixed refrigerant of R32 and HFO first fluid, carbon dioxide, ammonia, propane, etc. can be used. As the second fluid, any fluid having a lower boiling point than the first fluid can be used, for example, refrigerants such as R-32, HFO refrigerant, a mixed refrigerant of HFC-32 and HFO refrigerant, carbon dioxide, ammonia, propane, water, antifreeze, etc. can be used.

[0215] (4-4) Modification D

[0216] In the above-mentioned embodiment, the first heat exchanger 100 is formed in a manner that the first fluid flowing in the first flow path 220 and the second fluid flowing in the second flow path 230 become counter-flows, but the first heat exchanger 100 can also be formed in a manner that the first fluid flowing in the first flow path 220 and the second fluid flowing in the second flow path 230 become parallel flows.

[0217] (4-5) Modification E

[0218] In the above embodiment, the first flow tube 141a, the first flow tube 141b, the second flow tube 142a and the second flow tube 142b are all formed in the first frame 140, but it may also be that at least a portion of the first flow tube 141a, the first flow tube 141b, the second flow tube 142a and the second flow tube 142b are formed in the second frame 150.

[0219] (4-6) Modification F

[0220] The first connection parts 115a and 115b are not limited to the above-mentioned forms as long as one end is connected to the first flow port 111a and the other end is connected to the first heat transfer region 113. The first connection part 115a may also be provided with a first protrusion 117a. Furthermore, the first connection part 115b may also be provided with a first protrusion 117b.

[0221] like Fig.14 As shown, the first protrusion 117a divides the first connection portion 115a, limiting the force (pressure) received by the partition wall 130 from the first fluid. The first protrusion 117a is formed in a linear shape protruding from the first heat transfer region 113 toward the first connection portion 115a by a predetermined length when viewed from above. Although not shown in the figure, the first connection portion 115b provided below the first heat transfer plate 110 is also formed in the same shape, and a plurality of first protrusions 117b are provided.

[0222] (4-7) Modification G

[0223] like Fig.15 As shown, the first connection portion 115a of the first heat exchanger 100 of Modification G is a planar region provided outside the first flow port 111a and is provided with a plurality of first protrusions 117a formed in a circular shape in a plan view.

[0224] In the first heat exchanger 100 of modification G, the first heat transfer plate 110 has a gap 119a, which is a strip region where the first connection portion 115a is not provided over a predetermined width between the upper end portion and the first connection portion 115a when viewed from above. By having the gap 119a, it is possible to prevent the flow path length of the first connection portion 115a through which the first fluid passes from being longer than the flow path length of the second connection portion 125a through which the second fluid passes.

[0225] The first protrusions 117a are formed, for example, with a radius of 1 mm in a plan view and a height of 0.5 mm in the thickness direction DT, and are arranged in the length direction DL and the width direction DW at intervals of 1 mm. The first protrusions 117a are not limited, and are formed, for example, by stamping or etching. Although not shown in the figure, the first connection portion 115b provided below the first heat transfer plate 110 is also formed in the same shape, and a plurality of first protrusions 117b are provided.

[0226] The shape of the first protrusions 117a and 117b is not limited to a circle. The shape of the first protrusions 117a and 117b can be Figures 10 to 13 The second protrusion 128b may be any of the triangular shape, the quadrilateral shape, and the teardrop shape shown as an example of the second protrusion 128b. Furthermore, the shapes of the plurality of first protrusions 117a and 117b of the first connection parts 115a and 115b may be different from each other.

[0227] like Fig.16 As shown, the planar first connection portion 115a may be in a trapezoidal shape whose width increases from the first flow opening 111a toward the first heat transfer region 113. Although not shown in the figure, the first connection portion 115b provided below the first heat transfer plate 110 is formed similarly.

[0228] <Second embodiment>

[0229] (1) Hot water supply device 2

[0230] Reference Fig.12 A hot water supply device 2 including a first heat exchanger 100 according to a second embodiment of the present disclosure is described. The hot water supply device 2 heats water supplied from the outside. In the following description, the same reference numerals are used for features that are the same as or correspond to those of the first embodiment, and description thereof is omitted.

[0231] The hot water supply device 2 includes a first heat exchanger 100, a water circuit 50, a heat source side circuit 60, and a hot water supply tank 70. The water circuit 50 is a circuit for circulating water. The heat source side circuit 60 is a circuit for circulating carbon dioxide, which is a fluid having a lower boiling point than water. Heat exchange between water and carbon dioxide is performed in the first heat exchanger 100. In the present embodiment, the water circuit 50 is provided indoors, and the heat source side circuit 60 is provided outdoors.

[0232] Water is an example of the first fluid. Carbon dioxide is an example of the second fluid. The water circuit 50 is an example of the first fluid circuit. The heat source side circuit 60 is an example of the second fluid circuit.

[0233] (1-1) Water circuit 50

[0234] The water circuit 50 is composed of a water circulation pump 51 , a utilization-side heat exchanger 52 , and the first flow path 220 of the first heat exchanger 100 .

[0235] The water circulation pump 51 circulates water inside the water circuit 50. The water circulation pump 51 sucks water inside the water circuit 50 from the suction part 51a, and discharges it from the discharge part 51b.

[0236] The suction portion 51 a is connected to the first flow pipe 141 b of the first heat exchanger 100 .

[0237] The utilization side heat exchanger 52 exchanges heat between water circulating in the water circuit 50 and water stored in the hot water supply tank 70. The utilization side heat exchanger 52 is disposed inside the hot water supply tank 70 so that water passing therethrough can exchange heat with water stored in the hot water supply tank 70.

[0238] One end of the utilization side heat exchanger 52 is connected to the discharge portion 51 b of the water circulation pump 51 . The other end of the utilization side heat exchanger 52 is connected to the first flow pipe 141 a of the first heat exchanger 100 .

[0239] (1-2) Heat source side circuit 60

[0240] The heat source side circuit 60 is constituted by a heat source side compressor 61 , a heat source side expansion valve 62 , a heat source side heat exchanger 63 , and the second flow path 230 of the first heat exchanger 100 .

[0241] The heat source side compressor 61 sucks low-pressure gas-phase carbon dioxide in the heat source side circuit 60 from the suction portion 61 a , compresses it, and discharges it from the discharge portion 61 b ​​as high-pressure gas-phase carbon dioxide.

[0242] The discharge portion 61 b ​​is connected to the second flow pipe 142 a of the first heat exchanger 100 .

[0243] The heat source side expansion valve 62 functions as a decompression device that adjusts the flow rate of carbon dioxide circulating in the heat source side circuit 60 and decompresses the carbon dioxide.

[0244] One end of the heat source side expansion valve 62 is connected to the second flow pipe 142b of the first heat exchanger 100. The other end of the heat source side expansion valve 62 is connected to one end of the heat source side heat exchanger 63.

[0245] The heat source side heat exchanger 63 functions as an evaporator and performs heat exchange between carbon dioxide and a heat source (for example, outside air).

[0246] The other end of the heat source side heat exchanger 63 is connected to the suction portion 61 a of the heat source side compressor 61 .

[0247] (1-3) Hot water supply tank 70

[0248] The hot water supply tank 70 stores water supplied from the outside. The stored water exchanges heat with the water passing through the utilization side heat exchanger 42. The hot water supply tank 70 takes in the water supplied from the outside from the water inlet 70b and stores the water. The stored water is discharged from the water outlet 70a.

[0249] (1-4) Action

[0250] The operation of each part of the hot water supply device 2 during operation is described below. When the hot water supply device 2 starts operating, a control unit (not shown) drives the water circulation pump 51 and the heat source side compressor 61 to set the opening of the heat source side expansion valve 62 to an appropriate opening corresponding to the target temperature of the water discharged from the hot water supply tank 70.

[0251] (1-4-1) Operation of the water circuit 30

[0252] When the water circulation pump 51 is driven, the water sucked from the suction part 51a is discharged from the discharge part 51b. The discharged water exchanges heat with the water stored in the hot water supply tank 70 in the utilization side heat exchanger 52. The water circulating in the water circuit 30 that has undergone heat exchange enters the first flow path 220 through the first flow pipe 141a of the first heat exchanger 100. The water passing through the first flow path 220 absorbs heat from the carbon dioxide passing through the second flow path 230 (in other words, is heated by the carbon dioxide). The water circulating in the water circuit 30 that has absorbed heat flows out of the first flow path 220 through the first flow pipe 141b. The water circulation pump 51 sucks the water flowing out of the first flow path 220 from the suction part 51a and discharges it from the discharge part 51b.

[0253] (1-4-2) Operation of the Heat Source Side Circuit 60

[0254] The heat source side compressor 61 sucks low-pressure gas phase carbon dioxide in the heat source side circuit 60 from the suction part 61a, and discharges it from the discharge part 61b as high-pressure gas phase carbon dioxide. The high-pressure gas phase carbon dioxide enters the second flow path 230 through the second flow pipe 142a of the first heat exchanger 100. The first heat exchanger 100 condenses the high-pressure gas phase carbon dioxide by releasing heat to become high-pressure liquid phase carbon dioxide. At this time, the carbon dioxide releases heat to the water passing through the first flow path 220 of the first heat exchanger 100 (in other words, heats the water). The high-pressure liquid phase carbon dioxide flows out from the second flow path 230 through the second flow pipe 142b and reaches the heat source side expansion valve 62. The heat source side expansion valve 62 set with an appropriate opening reduces the pressure of the high-pressure liquid phase carbon dioxide to become low-pressure gas-liquid two-phase carbon dioxide. The low-pressure gas-liquid two-phase carbon dioxide reaches the heat source side heat exchanger 63. The heat source side heat exchanger 63 evaporates the low-pressure gas-liquid two-phase carbon dioxide to become low-pressure gas phase carbon dioxide. At this time, the carbon dioxide absorbs heat from the heat source (outside air). The carbon dioxide in the low-pressure gas phase flows out of the heat source side heat exchanger 63 and is sucked into the heat source side compressor 61 from the suction portion 61a.

[0255] (2) Features

[0256] In the hot water supply device 2, the first heat exchanger 100 also has the same effect as that in the case of being used in the refrigeration cycle device 1. Specifically, the pressure loss generated in the water when passing through the first connection parts 115a and 115b can be made smaller than the pressure loss generated in the carbon dioxide when passing through the second connection parts 125a and 125b. Thus, the pressure of the water is suppressed from decreasing at a large ratio. Therefore, according to the first heat exchanger 100, even if there is a difference in pressure when the two fluids flow in, the heat exchange performance can be ensured.

[0257] As mentioned above, although embodiment of this disclosure is described, it should be understood that various changes in form and detail are possible without departing from the spirit and scope of this disclosure described in the claims.

[0258] Description of symbols

[0259] 1Refrigeration cycle device

[0260] 2 Hot water supply device

[0261] 10First fluid circuit

[0262] 20 Second fluid circuit

[0263] 30 Water circuit (refrigeration circulation device)

[0264] 40 Control Department

[0265] 50 water circuit (hot water supply)

[0266] 60 heat source side circuit

[0267] 100 First Heat Exchanger

[0268] 110 first heat transfer plate

[0269] 111a, 111b first flow port

[0270] 112a, 112b first through hole

[0271] 113 First heat transfer area

[0272] 115a, 115b first connection portion

[0273] 116a, 116b first separation part

[0274] 117a, 117b first protrusion

[0275] 120 second heat transfer plate

[0276] 121a, 121b second flow port

[0277] 122a, 122b second through holes

[0278] 123 Second heat transfer area

[0279] 125a, 125b second connection portion

[0280] 126a, 126b second separation part

[0281] 127a, 127b second protrusion

[0282] 128b Second protrusion (circular shape)

[0283] 130 Next Door

[0284] DL length direction

[0285] DT thickness direction

[0286] DW width direction

[0287] Prior art literature

[0288] Patent Literature

[0289] Patent Document 1: Japanese Patent Application No. 2012-512382

Claims

1. A heat exchanger comprising a first heat transfer plate (110) and a second heat transfer plate (120) stacked on each other, The first heat transfer plate has: Two first flow ports (111a, 111b) for introducing or exporting a first fluid; two first through holes (112a, 112b) for allowing a second fluid having a boiling point lower than that of the first fluid to pass through in a thickness direction (DT); a first heat transfer region (113) through which the first fluid flowing in from the first flow port passes while exchanging heat with the second fluid; as well as A first connecting portion (115a, 115b), one end of which is connected to the first flow port, and the other end of which is connected to the first heat transfer area, The second heat transfer plate (120) has: A second flow port (121a, 121b), which is connected to the first through hole and introduces or discharges the second fluid; two second through holes (122a, 122b) for allowing the first fluid to pass through in a thickness direction; a second heat transfer region (123) through which the second fluid flowing in from the second flow port passes while exchanging heat with the first fluid; as well as A second connecting portion (125a, 125b) has one end connected to the second flow port and the other end connected to the second heat transfer region, The second flow port is formed at a position opposite to the second heat transfer region across the second through hole. The second connection portion is formed so as to bypass the outside of the second through hole and is provided with a second protrusion (127a, 127b, 128a, 128b).

2. The heat exchanger according to claim 1, wherein: The second protrusion is linear in plan view.

3. The heat exchanger according to claim 1 or 2, wherein: The second connection portion is linear in a plan view.

4. The heat exchanger according to claim 1, wherein: The second protrusion is circular in plan view (128b).

5. The heat exchanger according to claim 1, wherein: The second protrusion has a triangular shape in a plan view.

6. The heat exchanger according to claim 1, wherein: The second protrusion has a quadrilateral shape in a plan view.

7. The heat exchanger according to claim 1, wherein: The second protrusion has a teardrop shape in a plan view.

8. The heat exchanger according to claim 1, wherein: The first connection portion is formed such that a flow path cross-sectional area increases from the first flow port toward the first heat transfer region.

9. The heat exchanger according to claim 8, wherein: The first connecting portion is provided with a first protrusion (117a, 117b), The first protrusion is linear in plan view.

10. The heat exchanger according to claim 8, wherein: The first connecting portion is provided with a first protrusion, The first protrusion has a circular shape in a plan view.

11. The heat exchanger according to claim 8, wherein: The first connecting portion is provided with a first protrusion, The first protrusion has a triangular shape in a plan view.

12. The heat exchanger according to claim 8, wherein: The first connecting portion is provided with a first protrusion, The first protrusion has a quadrilateral shape in a plan view.

13. The heat exchanger according to claim 8, wherein: The first connecting portion is provided with a first protrusion, The first protrusion has a teardrop shape in a plan view.

14. The heat exchanger according to any one of claims 1 to 13, wherein: The heat exchanger includes a partition wall (130) which is a plate-shaped member stacked between the first heat transfer plate and the second heat transfer plate. The first connection portion is formed as follows: In a cross section orthogonal to the flow direction of the first fluid, when the length of the first separation portion (116a, 116b) that separates adjacent first connection portions from each other in contact with the partition wall is La1 and the interval between adjacent first separation portions is P1, the relationship 0.005<La1 / P1<0.15 is satisfied.

15. The heat exchanger according to claim 14, wherein: The first connection portion is formed to satisfy the relationship of 0.005<La1 / P1<0.

05.

16. The heat exchanger according to any one of claims 1 to 15, wherein: The heat exchanger includes a partition wall which is a plate-shaped member stacked between the first heat transfer plate and the second heat transfer plate. The second connection portion is formed as follows: In a cross section orthogonal to the flow direction of the second fluid, if the length of the second separation portion (126a, 126b) that separates adjacent second connection portions from each other or the second protrusion portion in contact with the partition wall is La2, and the interval between adjacent second separation portions or second protrusion portions is P2, the relationship 0.005<L2 / P2<0.15 is satisfied.

17. The heat exchanger according to claim 16, wherein: The plurality of second connection portions satisfy the relationship of 0.02<L2 / P2<0.

15.

18. A refrigerant cycle device comprising: The heat exchanger according to any one of claims 1 to 17; a first fluid circuit (10) for circulating the first fluid; and A second fluid circuit (20) for circulating the second fluid.

19. A hot water supplier, comprising: The heat exchanger according to any one of claims 1 to 17; a first fluid circuit (50) for circulating the first fluid; and A second fluid circuit (60) for circulating the second fluid.

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