EP4095476A1 - Heat exchanger and refrigeration cycle apparatus - Google Patents
Heat exchanger and refrigeration cycle apparatus Download PDFInfo
- Publication number
- EP4095476A1 EP4095476A1 EP20915558.9A EP20915558A EP4095476A1 EP 4095476 A1 EP4095476 A1 EP 4095476A1 EP 20915558 A EP20915558 A EP 20915558A EP 4095476 A1 EP4095476 A1 EP 4095476A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- flow path
- plate
- refrigerant
- shaped part
- heat exchanger
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
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- 238000005057 refrigeration Methods 0.000 title claims description 30
- 239000003507 refrigerant Substances 0.000 claims abstract description 411
- 238000012546 transfer Methods 0.000 claims abstract description 206
- 238000009826 distribution Methods 0.000 claims description 132
- 238000003780 insertion Methods 0.000 claims description 40
- 230000037431 insertion Effects 0.000 claims description 40
- 238000004891 communication Methods 0.000 claims description 21
- 230000007423 decrease Effects 0.000 claims description 10
- 230000000903 blocking effect Effects 0.000 description 20
- 239000007788 liquid Substances 0.000 description 20
- 239000012071 phase Substances 0.000 description 11
- 238000010438 heat treatment Methods 0.000 description 9
- 238000004378 air conditioning Methods 0.000 description 7
- 230000000694 effects Effects 0.000 description 7
- 238000001816 cooling Methods 0.000 description 6
- 238000005219 brazing Methods 0.000 description 4
- 230000005484 gravity Effects 0.000 description 4
- 239000012530 fluid Substances 0.000 description 3
- 238000005192 partition Methods 0.000 description 3
- 238000011144 upstream manufacturing Methods 0.000 description 3
- 230000003247 decreasing effect Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000009827 uniform distribution Methods 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 238000007710 freezing Methods 0.000 description 1
- 230000008014 freezing Effects 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000000116 mitigating effect Effects 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
Images
Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
- F28F9/00—Casings; Header boxes; Auxiliary supports for elements; Auxiliary members within casings
- F28F9/02—Header boxes; End plates
- F28F9/026—Header boxes; End plates with static flow control means, e.g. with means for uniformly distributing heat exchange media into conduits
- F28F9/0278—Header boxes; End plates with static flow control means, e.g. with means for uniformly distributing heat exchange media into conduits in the form of stacked distribution plates or perforated plates arranged over end plates
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
- F28F9/00—Casings; Header boxes; Auxiliary supports for elements; Auxiliary members within casings
- F28F9/02—Header boxes; End plates
- F28F9/0202—Header boxes having their inner space divided by partitions
- F28F9/0204—Header boxes having their inner space divided by partitions for elongated header box, e.g. with transversal and longitudinal partitions
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
- F28F9/00—Casings; Header boxes; Auxiliary supports for elements; Auxiliary members within casings
- F28F9/02—Header boxes; End plates
- F28F9/0219—Arrangements for sealing end plates into casing or header box; Header box sub-elements
- F28F9/0221—Header boxes or end plates formed by stacked elements
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
- F28D1/00—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators
- F28D1/02—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid
- F28D1/04—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid with tubular conduits
- F28D1/053—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid with tubular conduits the conduits being straight
- F28D1/0535—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid with tubular conduits the conduits being straight the conduits having a non-circular cross-section
- F28D1/05366—Assemblies of conduits connected to common headers, e.g. core type radiators
- F28D1/05383—Assemblies of conduits connected to common headers, e.g. core type radiators with multiple rows of conduits or with multi-channel conduits
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
- F28D21/00—Heat-exchange apparatus not covered by any of the groups F28D1/00 - F28D20/00
- F28D2021/0019—Other heat exchangers for particular applications; Heat exchange systems not otherwise provided for
- F28D2021/0068—Other heat exchangers for particular applications; Heat exchange systems not otherwise provided for for refrigerant cycles
Definitions
- the present disclosure relates to a heat exchanger, and a refrigeration cycle apparatus including the heat exchanger.
- Heat transfer tubes used in heat exchangers for air-conditioning apparatuses are becoming increasingly smaller to reduce the amount of refrigerant used or to improve heat exchanger performance.
- recent heat exchangers have increased number of passes (number of branches) in comparison to existing heat exchangers. Accordingly, such a heat exchanger is provided with a multi-pass refrigerant distributor (see, for example, Patent Literature 1).
- a heat exchanger described in Patent Literature 1 includes multiple heat transfer tubes, a header manifold, and multiple fins.
- the heat transfer tubes are arranged side by side.
- the header manifold which serves as a refrigerant distributor, is connected with one end of each heat transfer tube, and extends in the vertical direction.
- the fins are joined to the heat transfer tubes.
- the internal space of the header manifold is divided by a partition plate into a first space connected with one end of each heat transfer tube, and a second space located across the partition plate from the first space.
- a communication path is provided near the upper and lower ends of the partition plate to allow the first space and the second space to communicate with each other.
- Patent Literature 1 Japanese Unexamined Patent Application Publication No. 2015-68622
- the first space defines a flow path through which two-phase gas-liquid refrigerant flows upward
- the second space defines a circulation flow path that directs refrigerant back to a lower portion from an upper portion of the heat exchanger.
- the first space and the second space are located in the direction in which the tube paths of the heat transfer tubes extend.
- the above configuration causes the refrigerant distributor described in Patent Literature 1 to increase in size in the direction in which the tube paths of the heat transfer tubes extend. This means that, due to structural constraints, the heat transfer tubes have a decreased length in the direction in which the tube paths of the heat transfer tubes extend, and consequently the heat transfer tubes have a decreased heat transfer surface area. This may potentially lead to deteriorated heat exchange performance of the heat exchanger described in Patent Literature 1 in comparison to existing heat exchangers.
- the present disclosure is directed to addressing the above-mentioned problem. Accordingly, it is an object of the present disclosure to provide a heat exchanger and a refrigeration cycle apparatus that allow for increased heat transfer surface area of the heat transfer tubes, and include a compact refrigerant distributor that does not increase in size in the direction in which the tube paths of the heat transfer tubes extend.
- a heat exchanger includes a plurality of heat transfer tubes arranged at intervals in a first direction, and configured to circulate refrigerant in a second direction intersecting the first direction, and a refrigerant distributor connected to one end of each of the plurality of heat transfer tubes and configured to distribute the refrigerant to the plurality of heat transfer tubes.
- the refrigerant distributor includes, in its inside, a first flow path and a second flow path through which the refrigerant flows.
- the first flow path is formed so as to extend in the first direction, communicates with the plurality of heat transfer tubes, and is connected with an inflow tube configured to cause the refrigerant to flow into the refrigerant distributor.
- the second flow path is formed so as to extend in the first direction, with opposite ends thereof being connected with the first flow path, and is formed so as to be positioned in a third direction relative to the first flow path, when a direction intersecting a plane parallel to the first direction and to the second direction is defined as the third direction.
- a refrigeration cycle apparatus includes a heat exchanger according to an embodiment of the present disclosure.
- the heat exchanger includes a refrigerant distributor having, inside the refrigerant distributor, a first flow path and a second flow path through which refrigerant flows.
- the second flow path is formed so as to extend in the first direction, with opposite ends thereof being connected with the first flow path.
- the second flow path is formed so as to be positioned in a third direction relative to the first flow path, when a direction intersecting a plane parallel to the first direction and to the second direction is defined as the third direction.
- the above-mentioned configuration of the heat exchanger helps to prevent or reduce an increase in the size of the refrigerant distributor in the second direction in which refrigerant is circulated, and allows the heat exchanger to be enlarged, within a range of structural constraints, in the direction in which the tube paths of the heat transfer tubes extend.
- the heat exchanger 100 according to an embodiment of the present disclosure thus allows for increased heat transfer surface area of the heat transfer tubes, and also allows the refrigerant distributor to be made compact without an increase in the size of the refrigerant distributor in the direction in which the tube paths of the heat transfer tubes extend.
- a heat exchanger 100 and a refrigeration cycle apparatus 200 according to Embodiment 1 will be described below with reference to the drawings or other illustrations.
- the relative dimensions, shapes, and other features of various components may differ from those of the actual components.
- the same reference signs are used to indicate the same or corresponding elements or features throughout the specification.
- terms representing directions e.g., "upper”, “lower”, “right”, “left”, “front”, and “rear” are used as appropriate to facilitate understanding of the present disclosure, such terms are used for illustrative purposes only and not intended to limit the corresponding device or component to any particular placement or orientation.
- the relative positions of individual components, the directions of extension of individual components, and the directions of arrangement of individual components described herein basically correspond to those when an outdoor heat exchanger 105 is installed in a usable condition.
- Fig. 1 is a refrigerant circuit diagram illustrating the configuration of the refrigeration cycle apparatus 200 including the heat exchanger 100 according to Embodiment 1.
- dotted arrows represent the direction in which refrigerant flows in a refrigerant circuit 110 during cooling operation
- solid arrows represent the direction in which refrigerant flows in the refrigerant circuit 110 during heating operation.
- an air-conditioning apparatus will be described as an example of the refrigeration cycle apparatus 200.
- the refrigeration cycle apparatus 200 is used for, for example, refrigeration or air-conditioning purposes, such as for refrigerators or freezers, vending machines, air-conditioning apparatuses, refrigeration apparatuses, or water heaters.
- the illustrated refrigerant circuit 110 is given only by way of example, and configurations of circuit elements or other features are not limited to the particular details described below with reference to the embodiment but can be changed or modified as appropriate within the technical scope of the embodiment.
- the refrigeration cycle apparatus 200 includes the refrigerant circuit 110.
- the refrigerant circuit 110 includes the following components connected sequentially via a refrigerant pipe; a compressor 101, a flow switching device 102, an indoor heat exchanger 103, a pressure reducing device 104, and the outdoor heat exchanger 105.
- the refrigeration cycle apparatus 200 includes an outdoor unit 106, and an indoor unit 107.
- the outdoor unit 106 accommodates the following components: the compressor 101; the flow switching device 102; the outdoor heat exchanger 105; the pressure reducing device 104; and an outdoor fan 108 configured to supply outside air to the outdoor heat exchanger 105.
- the indoor unit 107 accommodates the indoor heat exchanger 103, and an indoor fan 109 configured to supply air to the indoor heat exchanger 103.
- the outdoor unit 106 and the indoor unit 107 are connected with each other via two extension pipes, an extension pipe 111 and an extension pipe 112, which form a portion of the refrigerant pipe.
- the compressor 101 is a piece of fluid machinery that compresses sucked refrigerant and discharges the compressed refrigerant.
- the flow switching device 102 is, for example, a four-way valve.
- the flow switching device 102 is configured to, under control by a controller (not illustrated), switch the flows of refrigerant between cooling operation and heating operation.
- Refrigerant is a first heat exchange fluid.
- the indoor heat exchanger 103 is a heat exchanger configured to cause heat exchange to be performed between refrigerant flowing inside the indoor heat exchanger 103, and indoor air supplied by the indoor fan 109.
- the indoor heat exchanger 103 functions as a condenser during heating operation, and functions as an evaporator during cooling operation.
- the pressure reducing device 104 is, for example, an expansion valve, and configured to reduce the pressure of refrigerant.
- a suitable example of the pressure reducing device 104 is an electronic expansion valve whose opening degree is adjusted through control by the controller.
- the outdoor heat exchanger 105 is a heat exchanger configured to cause heat exchange to be performed between refrigerant flowing inside the outdoor heat exchanger 105, and air supplied by the outdoor fan 108.
- the outdoor heat exchanger 105 functions as an evaporator during heating operation, and functions as a condenser during cooling operation.
- Air supplied by the outdoor fan 108 is an example of a second heat exchange fluid.
- the heat exchanger 100 described later is used as at least one of the outdoor heat exchanger 105 and the indoor heat exchanger 103.
- a refrigerant distributor 150 connected with the heat exchanger 100 is desirably disposed at a location where the heat exchanger 100 receives an increased flow of liquid-phase refrigerant.
- the refrigerant distributor 150 is desirably disposed near the inlet of the heat exchanger 100 functioning as an evaporator, that is, near the outlet of the heat exchanger 100 functioning as a condenser.
- the refrigerant distributor 150 is depicted in Fig.
- the refrigerant distributor 150 may be used for only one of the two heat exchangers 100 including the indoor heat exchanger 103 and the outdoor heat exchanger 105.
- Fig. 1 describe an example of how the refrigeration cycle apparatus 200 operates.
- high-pressure and high-temperature refrigerant in a gaseous state discharged from the compressor 101 flows via the flow switching device 102 into the indoor heat exchanger 103, where the refrigerant condenses through heat exchange with air supplied by the indoor fan 109.
- the condensed refrigerant changes into a high-pressure liquid state, and then leaves the indoor heat exchanger 103.
- the resulting refrigerant is turned into a low-pressure, two-phase gas-liquid state by the pressure reducing device 104.
- the low-pressure refrigerant in the two-phase gas-liquid state flows into the outdoor heat exchanger 105, where the refrigerant evaporates through heat exchange with air supplied by the outdoor fan 108.
- the evaporated refrigerant changes into a low-pressure gaseous state before being sucked into the compressor 101.
- frost forms on the outdoor heat exchanger 105.
- refrigerant flows in the refrigerant circuit 110 in a direction opposite to the direction of flow during heating operation. That is, during cooling operation of the refrigeration cycle apparatus 200, high-pressure and high-temperature refrigerant in a gaseous state discharged from the compressor 101 flows via the flow switching device 102 into the outdoor heat exchanger 105, where the refrigerant condenses through heat exchange with air supplied by the outdoor fan 108. The condensed refrigerant changes into a high-pressure liquid state, and then leaves the outdoor heat exchanger 105. The resulting refrigerant is then turned into a low-pressure, two-phase gas-liquid state by the pressure reducing device 104.
- the low-pressure refrigerant in the two-phase gas-liquid state flows into the indoor heat exchanger 103, where the refrigerant evaporates through heat exchange with air supplied by the indoor fan 109.
- the evaporated refrigerant changes into a low-pressure gaseous state before being sucked into the compressor 101.
- Fig. 2 is a side view of the heat exchanger 100 according to Embodiment 1, conceptually illustrating the configuration of major components of the heat exchanger 100.
- Fig. 3 is an exploded perspective view of the heat exchanger 100 according to Embodiment 1, conceptually illustrating the configuration of major components of the heat exchanger 100.
- a hatched arrow F in Fig. 2 represents the direction of refrigerant flow in a first flow path portion 15 of the refrigerant distributor 150.
- the refrigerant distributor 150 is connected with an end of each of heat transfer tubes 70 that is an end through which refrigerant enters the heat transfer tube 70 when the heat exchanger 100 operates as an evaporator.
- the heat exchanger 100 includes multiple heat transfer tubes 70 configured to circulate refrigerant, and the refrigerant distributor 150 connected with one end of each of the heat transfer tubes 70 in a direction in which the tube path of the heat transfer tube 70 extends.
- the heat exchanger 100 also includes a refrigerant inflow tube 60 attached to a lower portion of the refrigerant distributor 150.
- the heat transfer tubes 70 are arranged at intervals in a first direction (Z-axis direction), and configured to circulate refrigerant in a second direction (X-axis direction) interesting the first direction (Z-axis direction).
- the heat transfer tubes 70 are flat tubes. Although the heat transfer tubes 70 will be described below as flat tubes, the heat transfer tubes 70 may not necessarily be flat tubes but may be, for example, circular tubes.
- the direction of arrangement of the heat transfer tubes 70, and the direction of extension of the refrigerant distributor 150 are each defined as a first direction (Z-axis direction). That is, the first direction is the direction in which the heat transfer tubes 70 are arranged.
- the direction of arrangement of the heat transfer tubes 70 which is the first direction (Z-axis direction)
- the up-down direction is, for example, the vertical direction.
- the direction of arrangement of the heat transfer tubes 70 which is defined as the first direction (Z-axis direction)
- the direction of arrangement of the heat transfer tubes 70 may not necessarily be the up-down direction or the vertical direction.
- the direction of arrangement of the heat transfer tubes 70 may be a direction inclined relative to the vertical direction, or may be the horizontal direction.
- the direction in which the tube paths of the heat transfer tubes 70 extend is defined as a second direction (X-axis direction).
- the tube paths of the heat transfer tubes 70 represent refrigerant passages 72 described later (see Fig. 4 ). Accordingly, the second direction (X-axis direction) is also the direction of refrigerant flow through the tube paths of the heat transfer tubes 70.
- the direction in which the tube paths of the heat transfer tubes 70 extend which is the second direction (X-axis direction)
- the direction in which the tube paths of the heat transfer tubes 70 extend which is defined as the second direction (X-axis direction)
- the direction in which the tube paths of the heat transfer tubes 70 extend which is defined as the second direction (X-axis direction)
- the direction in which the tube paths of the heat transfer tubes 70 extend may not necessarily be the horizontal direction.
- the direction in which the tube paths of the heat transfer tubes 70 extend may be a direction inclined relative to the horizontal direction, or may be the up-down direction including the vertical direction.
- a gap 71 through which air flows is defined between two adjacent heat transfer tubes 70.
- Heat transfer fins 75 may be disposed between two adjacent heat transfer tubes 70 as illustrated in Fig. 2 .
- a portion of the heat exchanger 100 may have the heat transfer fins 75 each serving as a heat transfer facilitating part, and a portion of the heat exchanger 100 may have a region where adjacent heat transfer tubes 70 are not connected with each other by a heat transfer facilitating part.
- Adjacent heat transfer tubes 70 may have no heat transfer fin 75, and may not be connected with each other by such a heat transfer facilitating part.
- a heat transfer facilitating part is a part used to facilitate heat transfer.
- An exemplary heat transfer facilitating part is a plate fin such as the heat transfer fin 75, or a corrugated fin. Accordingly, the outdoor heat exchanger 105 may be implemented as a so-called finless heat exchanger.
- the heat exchanger 100 functions as an evaporator for the refrigeration cycle apparatus 200, in each of the heat transfer tubes 70, refrigerant flows through each tube path inside the heat transfer tube 70 from one end to the other end in the direction in which the tube path extends. If the heat exchanger 100 functions as a condenser for the refrigeration cycle apparatus 200, in each of the heat transfer tubes 70, refrigerant flows through each tube path inside the heat transfer tube 70 from the other end to the one end in the direction in which the tube path extends.
- Fig. 4 illustrates, in cross-section, the configuration of each heat transfer tube 70 forming the heat exchanger 100 according to Embodiment 1.
- Fig. 4 illustrates a cross-section perpendicular to the direction in which each heat transfer tube 70 extends.
- each heat transfer tube 70 has a cross-sectional shape that is flattened in one direction, such as an oval shape.
- Each heat transfer tube 70 has a first side end 70a and a second side end 70b, and a pair of flat surfaces 70c and 70d.
- the first side end 70a is connected with one end of the flat surface 70c and with one end of the flat surface 70d.
- the second side end 70b is connected with the other end of the flat surface 70c and with the other end of the flat surface 70d.
- the first side end 70a is a side end located upstream, that is, at the leading edge with respect to the flow of air passing through the heat exchanger.
- the second side end 70b is a side end located downstream, that is, at the trailing edge with respect to the flow of air passing through the heat exchanger.
- a direction perpendicular to the direction of extension of each heat transfer tube 70 and along the flat surface 70c and the flat surface 70d is sometimes referred to as long-axis direction of the heat transfer tube 70.
- Each heat transfer tube 70 includes multiple refrigerant passages 72 arranged in the long-axis direction between the first side end 70a and the second side end 70b.
- Each heat transfer tube 70 is a flat multi-port tube with multiple refrigerant passages 72 arranged in the direction of air flow and through which refrigerant passes.
- Each of the refrigerant passages 72 extends in parallel to the direction of extension of the heat transfer tubes 70.
- the refrigerant distributor 150 has a body 151 extending in the first direction (Z-axis direction).
- the body 151 of the refrigerant distributor 150 is connected with one end of each of the heat transfer tubes 70.
- the refrigerant distributor 150 distributes refrigerant to each of the heat transfer tubes 70 connected with the body 151.
- the body 151 of the refrigerant distributor 150 is disposed in the direction of arrangement of the heat transfer tubes 70 such that the body 151 extends in the up-down direction.
- the body 151 has a distribution flow path extending in the first direction and defined inside the body 151 to distribute refrigerant to each of the heat transfer tubes 70.
- the body 151 of the refrigerant distributor 150 has a refrigerant inlet 18 that receives the refrigerant inflow tube 60 inserted into the refrigerant inlet 18, and multiple insertion holes 31 that each receive the corresponding one of the heat transfer tubes 70 inserted into the insertion hole 31.
- the refrigerant inlet 18 is located at or near one end 151a of the body 151 in the first direction.
- the insertion holes 31 are defined in a side of the body 151 that is connected with the heat transfer tubes 70.
- the insertion holes 31 are arranged at intervals in the first direction (Z-axis direction) in one-to-one correspondence to the heat transfer tubes 70.
- the body 151 of the refrigerant distributor 150 includes a first plate-shaped part 10, a second plate-shaped part 20, and a third plate-shaped part 30.
- the first plate-shaped part 10, the second plate-shaped part 20, and the third plate-shaped part 30 are each made of a flat metal plate formed into a strip elongated in one direction.
- the respective outer edges of the first plate-shaped part 10, the second plate-shaped part 20, and the third plate-shaped part 30 have identical contours.
- the first plate-shaped part 10, the second plate-shaped part 20, and the third plate-shaped part 30 are each disposed with the direction of its plate thickness being parallel to the direction in which the tube paths of the heat transfer tubes 70 extend, that is, with its plate plane being perpendicular to the direction in which the tube paths of the heat transfer tubes 70 extend.
- the first plate-shaped part 10, the second plate-shaped part 20, and the third plate-shaped part 30 are stacked in this order from the farthest to the closest to the heat transfer tubes 70.
- the first plate-shaped part 10 is located farthest to the heat transfer tubes 70
- the third plate-shaped part 30 is located closest to the heat transfer tubes 70.
- the second plate-shaped part 20 is disposed between the first plate-shaped part 10 and the heat transfer tubes 70, and adjacent to the first plate-shaped part 10 and the third plate-shaped part 30.
- the third plate-shaped part 30 is disposed between the second plate-shaped part 20 and the heat transfer tubes 70, and adjacent to the second plate-shaped part 20.
- the third plate-shaped part 30 is connected with one end of each of the heat transfer tubes 70.
- first plate-shaped part 10 Each adjacent two of the first plate-shaped part 10, the second plate-shaped part 20, and the third plate-shaped part 30 are joined to each other by brazing.
- the first plate-shaped part 10, the second plate-shaped part 20, and the third plate-shaped part 30 are each disposed with its longitudinal direction being aligned with the first direction (Z-axis direction).
- Fig. 5 is a cross-sectional view of the heat exchanger 100 according to Embodiment 1, conceptually illustrating where first and second flow paths of the refrigerant distributor 150 forming the heat exchanger 100 communicate with each other.
- the direction of plate thickness of each of the first plate-shaped part 10, the second plate-shaped part 20, and the third plate-shaped part 30 is the up-down direction in Fig. 5 , which coincides with the direction in which the tube paths of the heat transfer tubes 70 extend.
- the lateral direction of each of the first plate-shaped part 10, the second plate-shaped part 20, and the third plate-shaped part 30 is the left-right direction in Fig. 5 , which coincides with the long-axis direction of each heat transfer tube 70.
- the configuration of the body 151 of the refrigerant distributor 150 will be further described below with reference to Figs. 3 and 5 .
- the first plate-shaped part 10 has the first flow path portion 15 that bulges away from the heat transfer tubes 70.
- the first flow path portion 15 is tubular in shape, with a space defined inside its bulge.
- the first plate-shaped part 10 and the first flow path portion 15 of the refrigerant distributor 150 are formed as an integral component, the first plate-shaped part 10 and the first flow path portion 15 may be formed as separate components.
- the first flow path portion 15 extends in the longitudinal direction of the first plate-shaped part 10 from one longitudinal end of the first plate-shaped part 10 to the other longitudinal end.
- the first flow path portion 15 has the shape of a semicylinder.
- the first flow path portion 15 is closed at both ends in the direction of extension of the first flow path portion 15.
- the first flow path portion 15 When viewed in cross-section perpendicular to the first direction (Z-axis direction), the first flow path portion 15 has a semicircular shape, a semielliptical shape, or a semioval shape.
- the cross-sectional shape of the first flow path portion 15 may not necessarily be semicircular, semielliptical, or semioval, but may be, for example, rectangular.
- the first plate-shaped part 10 has a flat plate portion 11a and a flat plate portion 11b formed in the shape of a flat plate and located across the first flow path portion 15 from each other.
- the flat plate portion 11a and the flat plate portion 11b each extend in the longitudinal direction of the first plate-shaped part 10 from one longitudinal end of the first plate-shaped part 10 to the other longitudinal end.
- the first flow path portion 15 is located between the flat plate portion 11a and the flat plate portion 11b, and bulges relative to the flat plate portion 11a and the flat plate portion 11b in a direction opposite to the location of the heat transfer tubes 70.
- the first flow path portion 15 is open on its side near the heat transfer tubes 70.
- the flat plate portion 11a and the flat plate portion 11b will be sometimes generically referred to as flat plate portion 11.
- the first flow path portion 15 has, in its inside, a main flow path 15a extending in the up-down direction along the length of the first plate-shaped part 10.
- the main flow path 15a corresponds to a first flow path of the refrigerant distributor 150.
- the main flow path 15a serving as the first flow path is connected with the refrigerant inflow tube 60, which is connected with the refrigerant inlet 18.
- the main flow path 15a extends in the first direction (Z-axis direction) in which the heat transfer tubes 70 are arranged.
- the main flow path 15a serving as the first flow path extends while intersecting each of the heat transfer tubes 70.
- the main flow path 15a serving as the first flow path communicates with the tube paths of the heat transfer tubes 70 via distribution holes 26 described later, which are provided in the second plate-shaped part 20.
- the main flow path 15a When viewed in cross-section perpendicular to the first direction (Z-axis direction), the main flow path 15a has a semicircular shape, a semielliptical shape, or a semioval shape. That is, the main flow path 15a is a space having the shape of a semicircular cylinder, a semielliptical cylinder, or a semioval cylinder.
- the cross-sectional shape of the main flow path 15a may not necessarily be semicircular, semielliptical, or semioval, but may be, for example, rectangular.
- the main flow path 15a serving as the first flow path is formed so as to extend in the first direction (Z-axis direction), communicates with the heat transfer tubes 70, and is connected, at a lower end 15a2 in the first direction, with the refrigerant inflow tube 60 configured to cause refrigerant to flow into the refrigerant distributor 150.
- Two-phase gas-liquid refrigerant entering the main flow path 15a via the refrigerant inflow tube 60 flows upward in the main flow path 15a so as to travel from the one end 151a of the body 151 toward the other end 151b, and is distributed to each of the heat transfer tubes 70.
- the lower end of the first flow path portion 15 is connected with the refrigerant inflow tube 60.
- the main flow path 15a, and the internal space of the refrigerant inflow tube 60 communicate with each other.
- the refrigerant inflow tube 60 is configured to cause two-phase gas-liquid refrigerant to flow into the main flow path 15a when the heat exchanger 100 acts as an evaporator.
- the location of connection between the refrigerant inflow tube 60 and the first flow path portion 15 corresponds to the refrigerant inlet 18 through which refrigerant flows into the refrigerant distributor 150.
- the heat exchanger 100 functions as a condenser, liquid refrigerant flows downward in the main flow path 15a, and exits the heat exchanger 100 through the refrigerant inflow tube 60.
- the second plate-shaped part 20 has a sub-flow path 25, and the distribution holes 26.
- a direction intersecting a plane P parallel to the first direction (Z-axis direction) and the second direction (X-axis direction) is defined as a third direction.
- the third direction includes the Y-axis direction.
- each distribution hole 26 is located in the vicinity of the middle of the second plate-shaped part 20, and the sub-flow path 25 is located in the vicinity of each end of the second plate-shaped part 20. That is, with respect to the third direction (Y-axis direction), each distribution hole 26 is located in the vicinity of the middle of the second plate-shaped part 20, and the sub-flow path 25 is disposed beside both sides of the distribution hole 26.
- the sub-flow path 25 and the distribution holes 26 of the second plate-shaped part 20 may not necessarily be located at the above-mentioned positions in the second plate-shaped part 20.
- a part of the sub-flow path 25 disposed beside one side of the distribution holes 26, and a part of the sub-flow path 25 disposed beside the other side of the distribution holes 26 may communicate with each other at least in their respective one end portions in the first direction.
- the sub-flow path 25 is provided in the second plate-shaped part 20 so as to extend in the first direction (Z-axis direction). That is, the sub-flow path 25 is provided along the length of the second plate-shaped part 20 so as to extend in the up-down direction.
- the sub-flow path 25 corresponds to a second flow path of the refrigerant distributor 150.
- the sub-flow path 25 serving as the second flow path is provided in the body 151 of the refrigerant distributor 150 such that the sub-flow path 25 is connected at both ends with the main flow path 15a serving as the first flow path.
- the sub-flow path 25 defines a refrigerant flow path that provides communication between an upper end 15a1 of the main flow path 15a and the lower end 15a2 such that refrigerant that has reached the upper end 15a1 of the main flow path 15a is returned to the lower end 15a2 where the refrigerant inlet 18 is located.
- the main flow path 15a and the sub-flow path 25 define a circulation flow path for refrigerant.
- the body 151 of the refrigerant distributor 150 has the main flow path 15a and the sub-flow path 25 that are defined inside the body 151 and through which refrigerant flows.
- the main flow path 15a corresponds to the first flow path
- the sub-flow path 25 corresponds to the second flow path.
- the sub-flow path 25 serving as the second flow path is located in the third direction relative to the main flow path 15a serving as the first flow path. That is, the main flow path 15a and the sub-flow path 25 are located upstream and downstream in the direction of airflow created by the outdoor fan 108 or the indoor fan 109 illustrated in Fig. 1 .
- the sub-flow path 25 has a middle portion 25a, an inlet portion 25b, and an outlet portion 25c.
- the middle portion 25a defines a flow path extending in the first direction (Z-axis direction).
- the inlet portion 25b is located at one end 25a1 of the middle portion 25a in the first direction (Z-axis direction).
- the outlet portion 25c is located at the other end 25a2 of the middle portion 25a in the first direction (Z-axis direction).
- the inlet portion 25b and the outlet portion 25c are each provided in the body 151 of the refrigerant distributor 150 as a flow path extending in the third direction (Y-axis direction).
- the middle portion 25a of the sub-flow path 25 is sandwiched between the flat plate portion 11 of the first plate-shaped part 10, and a flat plate portion 34 of the third plate-shaped part 30.
- the sub-flow path 25 serving as the second flow path has the inlet portion 25b and the outlet portion 25c.
- the sub-flow path 25 is thus connected at its both ends with the main flow path 15a serving as the first flow path. More specifically, in the body 151 of the refrigerant distributor 150, the inlet portion 25b of the sub-flow path 25 serving as the second flow path communicates with the upper end 15a1 of the main flow path 15a. In the body 151 of the refrigerant distributor 150, the outlet portion 25c of the sub-flow path 25 serving as the second flow path communicates with the lower end 15a2 of the main flow path 15a.
- Refrigerant passes through the inlet portion 25b when flowing from the main flow path 15a serving as the first flow path into the sub-flow path 25 serving as the second flow path. That is, refrigerant flows into the inlet portion 25b from the main flow path 15a serving as the first flow path.
- Refrigerant passes through the outlet portion 25c when flowing from the sub-flow path 25 serving as the second flow path into the main flow path 15a serving as the first flow path. That is, refrigerant exits through the outlet portion 25c into the main flow path 15a serving as the first flow path.
- the sub-flow path 25 serving as the second flow path does not communicate with insertion holes 31, which will be described later, of the third plate-shaped part 30.
- the second plate-shaped part 20 of the body 151 of the refrigerant distributor 150 according to Embodiment 1 is described above as having multiple distribution holes 26, the second plate-shaped part 20 may have only a single distribution hole 26.
- the single distribution hole 26 extends in the first direction (Z-axis direction) in such a way that the distribution hole 26 corresponds to multiple heat transfer tubes 70.
- the second plate-shaped part 20 has a blocking portion 24 in the form of a flat plate. When viewed in the direction of plate thickness of the second plate-shaped part 20, the blocking portion 24 partially overlaps the main flow path 15a of the first plate-shaped part 10. The blocking portion 24 serves to prevent the main flow path 15a and each of the heat transfer tubes 70 from communicating with each other directly rather than via the corresponding distribution hole 26.
- the third plate-shaped part 30 has multiple insertion holes 31 each configured to receive one end of the corresponding one of the heat transfer tubes 70 inserted into the insertion hole 31.
- Each of the insertion holes 31 is a through-hole extending through the third plate-shaped part 30 in the direction of plate thickness of the third plate-shaped part 30.
- the insertion holes 31 are arranged in parallel in the up-down direction along the length of the third plate-shaped part 30.
- the insertion holes 31 are provided independently of each other in one-to-one correspondence to the heat transfer tubes 70.
- Each insertion hole 31 defines an opening with a flattened shape that conforms to the outer circumferential shape of the corresponding heat transfer tube 70. The entire circumference of the opening edge of each insertion hole 31 is joined by brazing to the outer circumferential surface of the corresponding heat transfer tube 70.
- the third plate-shaped part 30 has the flat plate portion 34 in the form of a flat plate.
- the flat plate portion 34 corresponds to a portion of the third plate-shaped part 30 that, when viewed in the direction of plate thickness of the third plate-shaped part 30, overlaps the sub-flow path 25 of the second plate-shaped part 20.
- the sub-flow path 25 serving as the second flow path is blocked by the flat plate portion 34 and the flat plate portion 11 in the second direction (X-axis direction).
- Fig. 6 conceptually illustrates how refrigerant flows within the refrigerant distributor 150 forming the heat exchanger 100 according to Embodiment 1. Reference is now made to an example of how the refrigerant distributor 150 according to Embodiment 1 operates when the heat exchanger 100 functions as an evaporator for the refrigeration cycle apparatus 200.
- refrigerant flows into the refrigerant distributor 150 in a two-phase gas-liquid state.
- the two-phase gas-liquid refrigerant flows into the body 151 through the refrigerant inflow tube 60 illustrated in Figs. 2 and 6 .
- the refrigerant inflow tube 60 illustrated in Figs. 2 and 6 .
- the refrigerant travels vertically upward in the main flow path 15a, which is defined in the first plate-shaped part 10, from the one end 151a toward the other end 151b.
- the refrigerant passes through each distribution hole 26 of the second plate-shaped part 20 and then through each insertion hole 31 of the third plate-shaped part 30 for distribution to each heat transfer tube 70.
- Fig. 7 illustrates the distribution of flow rate of refrigerant within the refrigerant distributor 150 forming the heat exchanger 100 according to Embodiment 1.
- the horizontal axis represents refrigerant flow rate [kg/h]
- the vertical axis represents the distance [m] from the refrigerant inlet 18 in the first direction in which the heat transfer tubes 70 are arranged.
- a dotted line A represents the flow rate at which refrigerant flows in the main flow path 15a if no sub-flow path 25 is present
- a solid line B represents the flow rate at which refrigerant flows in the main flow path 15a if the sub-flow path 25 is present.
- An alternate long and short dash line C represents a case where the flow rate of refrigerant in the main flow path 15a is constant in the up-down direction. If the flow rate of refrigerant in the main flow path 15a is constant in the up-down direction, then the flow rate of refrigerant into each of the heat transfer tubes 70 arranged in the first direction is constant. Accordingly, the closer the flow rate of refrigerant in the main flow path 15a is to the flow rate of refrigerant represented by the alternate long and short dash line C, the more desirable.
- liquid refrigerant accumulates in an upper portion of the main flow path 15a serving as the first flow path. This results in comparatively more liquid refrigerant being distributed in the upper portion of the main flow path 15a serving as the first flow path.
- the heat exchanger 100 includes the refrigerant distributor 150 that includes the main flow path 15a and the sub-flow path 25 through which refrigerant flows.
- the sub-flow path 25 serving as the second flow path is formed so as to extend in the first direction (Z-axis direction), with opposite ends thereof being connected with the main flow path 15a serving as the first flow path.
- the sub-flow path 25 serving as the second flow path is formed so as to be positioned in the third direction relative to the main flow path 15a serving as the first flow path, when a direction intersecting the plane P parallel to the first direction (Z-axis direction) and the second direction (X-axis direction) is defined as the third direction.
- the heat exchanger 100 allows for increased heat transfer surface area of the heat transfer tubes 70, in comparison to a heat exchanger having first and second flow paths that are provided in the direction in which the tube paths of the heat transfer tubes 70 extend.
- the heat exchanger 100 thus allows for improved heat exchange performance, in comparison to a heat exchanger having first and second flow paths that are provided in the direction in which the tube paths of the heat transfer tubes 70 extend. Therefore, the heat exchanger 100 provides improved mitigation of refrigerant maldistribution with respect to changes in refrigerant flow rate or quality that depend on the operating condition of an air-conditioning apparatus. This leads to improved distribution robustness, that is, the ability to accommodate a wider range of refrigerant flow rate or other conditions.
- the heat exchanger 100 has the sub-flow path 25.
- the presence of the sub-flow path 25 ensures that when an operating condition of the air-conditioning apparatus causes liquid refrigerant to accumulate in an upper portion of the main flow path 15a, the refrigerant is circulated from the upper portion of the main flow path 15a to the lower portion of the main flow path 15a. This helps to prevent or reduce maldistribution of refrigerant.
- the heat exchanger 100 including the refrigerant distributor 150 with the sub-flow path 25 thus allows for uniform distribution of refrigerant to each heat transfer tube 70, in comparison to a heat exchanger that includes a refrigerant distributor without the sub-flow path 25. This results in improved heat exchange performance of the heat exchanger 100 in comparison to a heat exchanger that includes a refrigerant distributor without the sub-flow path 25.
- the heat exchanger 100 allows for increased heat transfer surface area of the heat transfer tubes 70, and also allows the refrigerant distributor 150 to be made compact without an increase in the size of the refrigerant distributor 150 in the direction in which the tube paths of the heat transfer tubes 70 extend.
- the heat exchanger 100 allows for increased heat transfer surface area of the heat transfer tubes 70, and also allows the refrigerant distributor 150 to be made compact without an increase in the size of the refrigerant distributor 150 in the direction in which the tube paths of the heat transfer tubes 70 extend.
- Fig. 8 is an exploded perspective view of the heat exchanger 100 according to Embodiment 2, conceptually illustrating the configuration of major components of the heat exchanger 100.
- Fig. 9 is a cross-sectional view of the heat exchanger 100 according to Embodiment 2, conceptually illustrating where the first and second flow paths of the refrigerant distributor 150 forming the heat exchanger 100 communicate with each other.
- Components identical in function and operation to the components described above with reference to Embodiment 1 are designated by the same reference signs and not described in further detail below.
- the heat exchanger 100 according to Embodiment 2 differs from the heat exchanger 100 according to Embodiment 1 in that the refrigerant distributor 150 further includes a fourth plate-shaped part 40 and a fifth plate-shaped part 50.
- the body 151 of the refrigerant distributor 150 includes the first plate-shaped part 10, the second plate-shaped part 20, the third plate-shaped part 30, the fourth plate-shaped part 40, and the fifth plate-shaped part 50.
- the fourth plate-shaped part 40 and the fifth plate-shaped part 50 are each made of a flat metal plate formed into a strip elongated in one direction.
- the respective outer edges of the first plate-shaped part 10, the second plate-shaped part 20, the third plate-shaped part 30, the fourth plate-shaped part 40, and the fifth plate-shaped part 50 have identical contours.
- the first plate-shaped part 10, the second plate-shaped part 20, the third plate-shaped part 30, the fourth plate-shaped part 40, and the fifth plate-shaped part 50 are each disposed with the direction of its plate thickness being parallel to the direction in which the tube paths of the heat transfer tubes 70 extend. That is, the first plate-shaped part 10, the second plate-shaped part 20, the third plate-shaped part 30, the fourth plate-shaped part 40, and the fifth plate-shaped part 50 are each disposed with its plate plane being perpendicular to the direction in which the tube paths of the heat transfer tubes 70 extend.
- Adjacent two of the first plate-shaped part 10, the fourth plate-shaped part 40, the second plate-shaped part 20, the fifth plate-shaped part 50, and the third plate-shaped part 30 are joined to each other by brazing.
- the first plate-shaped part 10, the fourth plate-shaped part 40, the second plate-shaped part 20, the fifth plate-shaped part 50, and the third plate-shaped part 30 are each disposed with its longitudinal direction being aligned with the first direction (Z-axis direction).
- the fourth plate-shaped part 40 has communication holes 45, and second distribution holes 46.
- the communication holes 45 are located between the main flow path 15a serving as the first flow path, and each end of the sub-flow path 25.
- the second distribution holes 46 are located between the main flow path 15a serving as the first flow path, and the second distribution holes 46.
- the communication holes 45 and the second distribution holes 46 are through-holes.
- each communication hole 45 is depicted in Fig. 8 as a through-hole defining a rectangular opening, this is not intended to limit the shape of the opening defined by the communication hole 45 to a rectangle.
- each communication hole 45 provides communication between the main flow path 15a serving as the first flow path and the sub-flow path 25 serving as the second flow path, and serves as a flow path that interconnects the main flow path 15a serving as the first flow path and the sub-flow path 25 serving as the second flow path.
- each second distribution hole 46 may not necessarily have a circular shape.
- the opening may have a semicircular shape, a semielliptical shape, a semioval shape, or a rectangular shape.
- the second distribution holes 46 define flow paths with the same cross-sectional area.
- the second distribution holes 46 may not necessarily define flow paths with the same cross-sectional area, but may define flow paths with different cross-sectional areas.
- the fourth plate-shaped part 40 of the body 151 of the refrigerant distributor 150 according to Embodiment 2 is described above as having multiple second distribution holes 46, the fourth plate-shaped part 40 may have only a single second distribution hole 46.
- the single second distribution hole 46 is formed so as to extend in the first direction (Z-axis direction) such that the second distribution hole 46 corresponds to multiple heat transfer tubes 70.
- each of the second distribution holes 46 overlaps the main flow path 15a of the first plate-shaped part 10.
- each of the second distribution holes 46 overlaps the corresponding one of the distribution holes 26 of the second plate-shaped part 20.
- each of the second distribution holes 46 overlaps the corresponding one of the third distribution holes 51 of the fifth plate-shaped part 50.
- each of the second distribution holes 46 overlaps the corresponding one of the insertion holes 31 of the third plate-shaped part 30.
- each of the second distribution holes 46 overlaps the corresponding one of the heat transfer tubes 70.
- the fifth plate-shaped part 50 has multiple third distribution holes 51 each defining a circular opening. Each third distribution hole 51 is located in the vicinity of the middle of the fifth plate-shaped part 50 in the third direction (Y-axis direction).
- the third distribution holes 51 define flow paths between the main flow path 15a and the heat transfer tubes 70, together with the distribution holes 26 of the second plate-shaped part 20 and the second distribution holes 46 of the fourth plate-shaped part 40.
- Each third distribution hole 51 is configured to distribute refrigerant to the corresponding heat transfer tube 70.
- the fifth plate-shaped part 50 of the body 151 of the refrigerant distributor 150 according to Embodiment 1 is described above as having multiple third distribution holes 51, the fifth plate-shaped part 50 may have only a single third distribution hole 51.
- the single third distribution hole 51 is formed so as to extend in the first direction (Z-axis direction) such that the third distribution hole 51 corresponds to multiple heat transfer tubes 70.
- each of the third distribution holes 51 overlaps the main flow path 15a of the first plate-shaped part 10.
- each of the third distribution holes 51 overlaps the corresponding one of the distribution holes 26 of the second plate-shaped part 20.
- each of the third distribution holes 51 overlaps the corresponding one of the second distribution holes 46 of the fourth plate-shaped part 40.
- each of the third distribution holes 51 overlaps the corresponding one of the insertion holes 31 of the third plate-shaped part 30.
- each of the third distribution holes 51 overlaps the corresponding one of the heat transfer tubes 70.
- the third distribution holes 51 are located between the heat transfer tubes 70, and the main flow path 15a serving as the first flow path.
- the main flow path 15a of the first plate-shaped part 10, and each of the heat transfer tubes 70 communicate with each other via the corresponding one of the third distribution holes 51.
- the fifth plate-shaped part 50 has a blocking portion 53 in the form of a flat plate. When viewed in the direction of plate thickness of the fifth plate-shaped part 50, the blocking portion 53 partially overlaps the main flow path 15a of the first plate-shaped part 10. The blocking portion 53 serves to prevent the main flow path 15a and each of the heat transfer tubes 70 from communicating with each other directly rather than via the corresponding third distribution hole 51.
- the blocking portion 53 covers a portion of the sub-flow path 25 from a side of the sub-flow path 25 that is located near the third plate-shaped part 30.
- the blocking portion 53 covers at least the middle portion 25a of the sub-flow path 25 from a side of the sub-flow path 25 that is located near the third plate-shaped part 30.
- the blocking portion 53 forms a portion of the tube path defining the sub-flow path 25.
- the refrigerant Upon reaching the lower end of the middle portion 25a of the sub-flow path 25, the refrigerant exits through the outlet portion 25c into the main flow path 15a via the communication holes 45 that communicate with the lower end 15a2 of the main flow path 15a.
- the refrigerant flows inward in the third direction from the sub-flow path 25 serving as the second flow path toward the main flow path 15a serving as the first flow path.
- the exiting refrigerant together with the refrigerant flowing into the body 151 through the refrigerant inflow tube 60, travels vertically upward in the main flow path 15a, and is distributed to each heat transfer tube 70.
- Fig. 11 illustrates the distribution of flow rate of refrigerant within the refrigerant distributor 150 forming the heat exchanger 100 according to Embodiment 2.
- the horizontal axis represents refrigerant flow rate [kg/h]
- the vertical axis represents the distance [m] from the refrigerant inlet 18 in the first direction in which the heat transfer tubes 70 are arranged.
- liquid refrigerant that accumulates in an upper portion of the main flow path 15a returns to a lower portion of the main flow path 15a by way of the sub-flow path 25.
- the flow rate of refrigerant decreases in the upper portion of the main flow path 15a as the refrigerant returns to the lower portion of the main flow path 15a.
- the flow rate of refrigerant increases in the lower portion of the main flow path 15a as the refrigerant returns to the lower portion from the upper portion of the main flow path 15a. Consequently, as represented by the solid line B, the flow rate at which refrigerant flows in the main flow path 15a if the sub-flow path 25 is present is closer to the flow rate represented by the alternate long and short dash line C, than is the flow rate at which refrigerant flows in the main flow path 15a if no sub-flow path 25 is present. Therefore, the refrigerant distributor 150 with the sub-flow path 25 allows refrigerant to be evenly distributed to each heat transfer tube 70, in comparison to a refrigerant distributor without the sub-flow path 25.
- the refrigerant distributor 150 includes the fourth plate-shaped part 40, and the fifth plate-shaped part 50.
- the fourth plate-shaped part 40 has the communication holes 45, which are located between the main flow path 15a serving as the first flow path and each end of the sub-flow path 25, and the second distribution holes 46, which are located between the main flow path 15a serving as the first flow path and the distribution holes 26.
- the fifth plate-shaped part 50 has the third distribution holes 51 located between the distribution holes 26 and the insertion holes 31.
- the sub-flow path 25 can be provided in the second plate-shaped part 20 such that, when viewed in the direction of stacking of the plate-shaped parts, the sub-flow path 25 overlaps the main flow path 15a of the first plate-shaped part 10, and the insertion holes 31 of the third plate-shaped part 30.
- the sub-flow path 25 provided in the second plate-shaped part 20 can be increased in width in the third direction (Y-axis direction). This leads to increased volume of the sub-flow path 25.
- the pressure loss in the sub-flow path 25 decreases and, consequently, when the circulation flow rate is high, a large amount of refrigerant that accumulates in the upper portion is allowed to circulate. This helps to prevent or reduce refrigerant maldistribution, and consequently improve the performance of the heat exchanger 100.
- the sub-flow path 25 has the middle portion 25a, the inlet portion 25b, and the outlet portion 25c1.
- the middle portion 25a defines a flow path extending in the first direction (Z-axis direction).
- the outlet portion 25c1 is located at the other end 25a2 of the middle portion 25a in the first direction (Z-axis direction).
- a tube axis TA of the outlet portion 25c1 is inclined toward a diagonal line DL of the second plate-shaped part 20 relative to the first direction (Z-axis direction) and the third direction (Y-axis direction). Therefore, as represented by the arrow IF and the arrow UF in Fig. 14 , the outlet portion 25c1 is inclined relative to the first direction and the third direction such that the direction of flow of refrigerant exiting the outlet portion 25c1 has a vector component of the direction of flow of refrigerant exiting the refrigerant inflow tube 60. That is, refrigerant exiting the outlet portion 25c1 is directed along the flow of refrigerant flowing in the main flow path 15a.
- an outlet angle ⁇ which is an angle between the direction of the tube axis TA of the outlet portion 25c1 and the direction of gravity GD, is greater than or equal to 90 degrees.
- Fig. 15 illustrates the distribution of flow rate of refrigerant within the refrigerant distributor 150 forming the heat exchanger 100 according to Embodiment 3.
- the horizontal axis represents refrigerant flow rate [kg/h]
- the vertical axis represents the distance [m] from the refrigerant inlet 18 in the first direction in which the heat transfer tubes 70 are arranged.
- liquid refrigerant that accumulates in an upper portion of the main flow path 15a returns to a lower portion of the main flow path 15a by way of the sub-flow path 25.
- the flow rate of refrigerant decreases in the upper portion of the main flow path 15a as the refrigerant returns to the lower portion of the main flow path 15a.
- Fig. 16 is an exploded perspective view of the heat exchanger 100 according to Embodiment 4, conceptually illustrating the configuration of major components of the heat exchanger 100.
- Fig. 17 is a cross-sectional view of the heat exchanger 100 according to Embodiment 4, conceptually illustrating where the first and second flow paths of the refrigerant distributor 150 forming the heat exchanger 100 communicate with each other.
- Fig. 18 conceptually illustrates how refrigerant flows within the refrigerant distributor 150 forming the heat exchanger 100 according to Embodiment 4. Components identical in function and operation to the components described above with reference to Embodiment 1 are designated by the same reference signs and not described in further detail below.
- the heat exchanger 100 according to Embodiment 4 differs from the heat exchanger 100 according to Embodiment 1 in that Embodiment 4 further specifies the configuration of the main flow path 15a serving as the first flow path.
- the first flow path portion 15 extends in the longitudinal direction of the first plate-shaped part 10 from the one end 151a of the main body portion toward the other end 151b.
- the first flow path portion 15 is closed at both ends in the direction of extension of the first flow path portion 15.
- the first flow path portion 15 has a side wall 15b having the shape of a trapezoid when viewed in the direction of stacking of the first plate-shaped part 10, the second plate-shaped part 20, and the third plate-shaped part 30.
- the first flow path portion 15 has the shape of a quadrangular prism with the side wall 15b.
- the first flow path portion 15 is tapered in the longitudinal direction of the first plate-shaped part 10 from the lower end 15a2 near the refrigerant inlet 18 toward the upper end 15a1.
- the first flow path portion 15 may not necessarily have the shape of a quadrangular prism with the side wall 15b but may have another shape, such as a circular truncated cone or a polygonal truncated cone.
- the main flow path 15a serving as the first flow path decreases in cross-sectional area from the lower end 15a2, which is one end communicating with the refrigerant inflow tube 60, toward the upper end 15a1, which is the other end. In the first direction (Z-axis direction), the main flow path 15a decreases in cross-sectional area toward the vertically upper portion of the main flow path 15a. This leads to increased flow rate of refrigerant through the main flow path 15a in the refrigerant distributor 150 of the heat exchanger 100.
- the refrigerant distributor 150 of the heat exchanger 100 allows refrigerant to reach the uppermost part of the main flow path 15a to thereby prevent or reduce maldistribution of refrigerant.
- Fig. 19 is an exploded perspective view of the heat exchanger 100 according to Embodiment 5, conceptually illustrating the configuration of major components of the heat exchanger 100.
- Fig. 20 is a conceptual side view of the interior of the refrigerant distributor 150 illustrated in Fig. 19 .
- Fig. 21 is a cross-sectional view of the heat exchanger 100 according to Embodiment 5, conceptually illustrating where the first and second flow paths of the refrigerant distributor 150 forming the heat exchanger 100 communicate with each other.
- Components identical in function and operation to the components described above with reference to Embodiment 1 are designated by the same reference signs and not described in further detail below.
- the refrigerant distributor 150 is a stack of multiple parts such as the first to fifth plate-shaped parts 10 to 50.
- the body 151 of the refrigerant distributor 150 according to Embodiment 5 is a tubular part.
- the tubular portion 90 is in the form of a hollow circular cylinder extending in the direction of arrangement of the heat transfer tubes 70.
- the tubular portion 90 may not necessarily be in the form of a circular cylinder but may be in any tubular form.
- the tubular portion 90 may be in the form of a cuboid box.
- the tubular portion 90 has a first tubular portion 90a that connects with the refrigerant inflow tube 60, and a second tubular portion 90b that connects with the heat transfer tubes 70.
- the first tubular portion 90a and the second tubular portion 90b each have the shape of a semicircular arc when viewed in cross-section perpendicular to the first direction (Z-axis direction).
- the first tubular portion 90a and the second tubular portion 90b of the tubular portion 90 may not be separate components.
- the first tubular portion 90a and the second tubular portion 90b may be integral with each other.
- the wall 91 is in the form of a strip elongated in one direction.
- the wall 91 is a plate-shaped portion extending in the direction of arrangement of the heat transfer tubes 70.
- the longitudinal direction of the wall 91 aligns with the first direction (Z-axis direction) in which the heat transfer tubes 70 are arranged.
- the lateral direction of the wall 91 aligns with the second direction (X-axis direction) in which the tube paths of the heat transfer tubes 70 extend.
- the direction of plate thickness of the wall 91 aligns with the long-axis direction of each heat transfer tube 70.
- the wall 91 defines a plate plane extending in the first direction (Z-axis direction) and the second direction (X-axis direction).
- the wall 91 has the outlet portion 92b at one end 91b, which is an end connected with the refrigerant inflow tube 60.
- the wall 91 has the inlet portion 92a at the other end 91a.
- the inlet portion 92a and the outlet portion 92b are through-holes extending through the wall 91 in the direction of plate thickness of the wall 91.
- the inlet portion 92a and the outlet portion 92b each define a flow path that extends in the third direction.
- the wall 91 has multiple insertion holes 93 each configured to receive one end of the corresponding one of the heat transfer tubes 70 inserted into the insertion hole 93.
- Each of the insertion holes 93 is a through-hole extending through the wall 91 in the direction of plate thickness of the wall 91.
- Each of the insertion holes 93 is a cutout extending from an edge 91e, which extends in the first direction (Z-axis direction), toward an edge 91d opposite to the edge 91e.
- the insertion holes 93 are arranged in parallel in the up-down direction along the length of the wall 91.
- the insertion holes 93 are provided independently of each other in one-to-one correspondence to the heat transfer tubes 70.
- Each insertion hole 93 defines an opening with a flattened shape that conforms to the outer circumferential shape of the corresponding heat transfer tube 70.
- the entire circumference of the opening edge of each insertion hole 93 is joined by brazing to the outer circumferential surface of the corresponding heat transfer tube 70.
- the lid 94 closes both ends of the tubular portion 90 in the direction in which the tubular portion 90 extends.
- the lid 94 may be any part for closing both ends of the tubular portion 90 in the direction in which the tubular portion 90 extends.
- the lid 94 may be a plate-shaped part, or may be a part that overlies both ends of the tubular portion 90.
- the hollow portion 95 inside the tubular portion 90 is defined by the tubular portion 90, and the lid 94 that closes both ends of the tubular portion 90. As illustrated in Fig. 21 , the hollow portion 95 inside the tubular portion 90 is divided by the wall 91 into two spaces, a first space S1 and a second space S2. The first space S1 and the second space S2 communicate with each other via the inlet portion 92a and the outlet portion 92b.
- the first space S1 defines the main flow path 15a.
- the main flow path 15a is a flow path through which refrigerant flows from the one end 151a of the body 151, which is an end connected with the refrigerant inflow tube 60, to the other end 151b.
- first direction Z-axis direction
- refrigerant flows upward in the main flow path 15a.
- the main flow path 15a serving as the first flow path is formed so as to extend in the first direction (Z-axis direction), communicates with the heat transfer tubes 70, and is connected, at the lower end 15a2 in the first direction, with the refrigerant inflow tube 60 configured to cause refrigerant to flow into the refrigerant distributor 150.
- the second space S2 In the body 151 of the refrigerant distributor 150, the second space S2, the inlet portion 92a, and the outlet portion 92b define the sub-flow path 25.
- the sub-flow path 25 is a flow path through which refrigerant flows from the other end 151b to the one end 151a of the body 151, which is an end connected with the refrigerant inflow tube 60.
- the first direction Z-axis direction
- refrigerant flows downward in the sub-flow path 25.
- the sub-flow path 25 serving as the second flow path extends in the first direction, with the inlet portion 92a and the outlet portion 92b at opposite ends being connected with the main flow path 15a serving as the first flow path.
- the sub-flow path 25 serving as the second flow path is located in the third direction relative to the main flow path 15a serving as the first flow path. That is, the main flow path 15a and the sub-flow path 25 are located upstream and downstream in the direction of airflow created by the outdoor fan 108 or the indoor fan 109 illustrated in Fig. 1 .
- the body 151 of the refrigerant distributor 150 includes, in its inside, the main flow path 15a serving as the first flow path, and the sub-flow path 25 serving as the second flow path, which are flow paths through which refrigerant flows.
- the main flow path 15a and the sub-flow path 25 define a flow path in which refrigerant circulates.
- the refrigerant Upon reaching the lower end of the sub-flow path 25, the refrigerant exits the sub-flow path 25 into the main flow path 15a through the outlet portion 92b communicating with the lower end 15a2 of the main flow path 15a.
- the refrigerant flows in the third direction from the sub-flow path 25 serving as the second flow path toward the main flow path 15a serving as the first flow path.
- the exiting refrigerant together with the refrigerant flowing into the body 151 through the refrigerant inflow tube 60, travels vertically upward in the main flow path 15a, and is distributed to each heat transfer tube 70.
- the refrigerant distributor 150 includes the tubular portion 90, the lid 94, and the wall 91.
- the wall 91 divides the main flow path 15a serving as the first flow path, and the sub-flow path 25 serving as the second flow path from each other in the third direction.
- the wall 91 has the inlet portion 92a and the outlet portion 92b, which are through-holes and located at opposite ends of the wall 91 in the first direction.
- the heat transfer tubes 70 are connected to the wall 91 so as to communicate with the main flow path 15a serving as the first flow path and the sub-flow path 25 serving as the second flow path.
- the above-mentioned configuration of the heat exchanger 100 helps to prevent or reduce an increase in the size of the refrigerant distributor 150 in the second direction in which refrigerant is circulated, and allows the heat exchanger 100 to be enlarged, within a range of structural constraints, in the second direction in which the tube paths of the heat transfer tubes 70 extend. Therefore, the heat exchanger 100 allows for increased heat transfer surface area of the heat transfer tubes 70, and also allows the refrigerant distributor 150 to be made compact without an increase in the size of the refrigerant distributor 150 in the direction in which the tube paths of the heat transfer tubes 70 extend.
- the refrigeration cycle apparatus 200 includes the heat exchanger 100 according to any one of Embodiments 1 to 5. Accordingly, the refrigeration cycle apparatus 200 provides an effect similar to any one of Embodiments 1 to 5.
- Embodiments 1 to 5 mentioned above can be practiced in combination with each other.
- the configurations described above with reference to the embodiments are intended to be illustrative only. These configurations can be combined with other known techniques, or can be partially omitted or changed without departing from the scope of the present disclosure.
- the refrigerant distributor 150 or other components according to Embodiments 1 to 5 may be of a longitudinally mounted type with the body 151 extending in the vertical direction, or may be of a transversely mounted type with the body 151 extending in the horizontal direction.
- the refrigerant distributor 150 or other components according to Embodiment 1 to 5 may be designed such that the body 151 is inclined relative to the vertical direction.
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Abstract
Description
- The present disclosure relates to a heat exchanger, and a refrigeration cycle apparatus including the heat exchanger.
- Heat transfer tubes used in heat exchangers for air-conditioning apparatuses are becoming increasingly smaller to reduce the amount of refrigerant used or to improve heat exchanger performance. To reduce an increase in the pressure loss of refrigerant associated with the trend toward smaller heat transfer tubes, recent heat exchangers have increased number of passes (number of branches) in comparison to existing heat exchangers. Accordingly, such a heat exchanger is provided with a multi-pass refrigerant distributor (see, for example, Patent Literature 1). To achieve balance between heat exchanger performance and reduction of the amount of refrigerant used, a need exists for a compact refrigerant distributor that prevents or reduces maldistribution of refrigerant flow among individual passes, allows for reduced volume of the distribution flow path to reduce the amount of refrigerant used, and does not interfere with the installation space for the heat exchanger while ensuring increased heat transfer surface area.
- A heat exchanger described in
Patent Literature 1 includes multiple heat transfer tubes, a header manifold, and multiple fins. The heat transfer tubes are arranged side by side. The header manifold, which serves as a refrigerant distributor, is connected with one end of each heat transfer tube, and extends in the vertical direction. The fins are joined to the heat transfer tubes. The internal space of the header manifold is divided by a partition plate into a first space connected with one end of each heat transfer tube, and a second space located across the partition plate from the first space. A communication path is provided near the upper and lower ends of the partition plate to allow the first space and the second space to communicate with each other. Due to the above configuration of the heat exchanger described inPatent Literature 1, refrigerant is looped between the first space and the second space. By allowing refrigerant to loop between the first space and the second space, the heat exchanger described inPatent Literature 1 makes it possible to reduce maldistribution of refrigerant. - Patent Literature 1:
Japanese Unexamined Patent Application Publication No. 2015-68622 - In the heat exchanger described in
Patent Literature 1, the first space defines a flow path through which two-phase gas-liquid refrigerant flows upward, and the second space defines a circulation flow path that directs refrigerant back to a lower portion from an upper portion of the heat exchanger. The first space and the second space are located in the direction in which the tube paths of the heat transfer tubes extend. The above configuration causes the refrigerant distributor described inPatent Literature 1 to increase in size in the direction in which the tube paths of the heat transfer tubes extend. This means that, due to structural constraints, the heat transfer tubes have a decreased length in the direction in which the tube paths of the heat transfer tubes extend, and consequently the heat transfer tubes have a decreased heat transfer surface area. This may potentially lead to deteriorated heat exchange performance of the heat exchanger described inPatent Literature 1 in comparison to existing heat exchangers. - The present disclosure is directed to addressing the above-mentioned problem. Accordingly, it is an object of the present disclosure to provide a heat exchanger and a refrigeration cycle apparatus that allow for increased heat transfer surface area of the heat transfer tubes, and include a compact refrigerant distributor that does not increase in size in the direction in which the tube paths of the heat transfer tubes extend.
- A heat exchanger according to an embodiment of the present disclosure includes a plurality of heat transfer tubes arranged at intervals in a first direction, and configured to circulate refrigerant in a second direction intersecting the first direction, and a refrigerant distributor connected to one end of each of the plurality of heat transfer tubes and configured to distribute the refrigerant to the plurality of heat transfer tubes. The refrigerant distributor includes, in its inside, a first flow path and a second flow path through which the refrigerant flows. The first flow path is formed so as to extend in the first direction, communicates with the plurality of heat transfer tubes, and is connected with an inflow tube configured to cause the refrigerant to flow into the refrigerant distributor. The second flow path is formed so as to extend in the first direction, with opposite ends thereof being connected with the first flow path, and is formed so as to be positioned in a third direction relative to the first flow path, when a direction intersecting a plane parallel to the first direction and to the second direction is defined as the third direction.
- A refrigeration cycle apparatus according to an embodiment of the present disclosure includes a heat exchanger according to an embodiment of the present disclosure.
- According to an embodiment of the present disclosure, the heat exchanger includes a refrigerant distributor having, inside the refrigerant distributor, a first flow path and a second flow path through which refrigerant flows. The second flow path is formed so as to extend in the first direction, with opposite ends thereof being connected with the first flow path. The second flow path is formed so as to be positioned in a third direction relative to the first flow path, when a direction intersecting a plane parallel to the first direction and to the second direction is defined as the third direction. The above-mentioned configuration of the heat exchanger helps to prevent or reduce an increase in the size of the refrigerant distributor in the second direction in which refrigerant is circulated, and allows the heat exchanger to be enlarged, within a range of structural constraints, in the direction in which the tube paths of the heat transfer tubes extend. The
heat exchanger 100 according to an embodiment of the present disclosure thus allows for increased heat transfer surface area of the heat transfer tubes, and also allows the refrigerant distributor to be made compact without an increase in the size of the refrigerant distributor in the direction in which the tube paths of the heat transfer tubes extend. -
- [
Fig. 1] Fig. 1 is a refrigerant circuit diagram illustrating the configuration of a refrigeration cycle apparatus including a heat exchanger according toEmbodiment 1. - [
Fig. 2] Fig. 2 is a side view of the heat exchanger according toEmbodiment 1, conceptually illustrating the configuration of major components of the heat exchanger. - [
Fig. 3] Fig. 3 is an exploded perspective view of the heat exchanger according toEmbodiment 1, conceptually illustrating the configuration of major components of the heat exchanger. - [
Fig. 4] Fig. 4 illustrates, in cross-section, the configuration of a heat transfer tube forming the heat exchanger according toEmbodiment 1. - [
Fig. 5] Fig. 5 is a cross-sectional view of the heat exchanger according toEmbodiment 1, conceptually illustrating where first and second flow paths of a refrigerant distributor forming the heat exchanger communicate with each other. - [
Fig. 6] Fig. 6 conceptually illustrates how refrigerant flows within the refrigerant distributor forming the heat exchanger according toEmbodiment 1. - [
Fig. 7] Fig. 7 illustrates the distribution of flow rate of refrigerant within the refrigerant distributor forming the heat exchanger according toEmbodiment 1. - [
Fig. 8] Fig. 8 is an exploded perspective view of a heat exchanger according toEmbodiment 2, conceptually illustrating the configuration of major components of the heat exchanger. - [
Fig. 9] Fig. 9 is a cross-sectional view of the heat exchanger according toEmbodiment 2, conceptually illustrating where first and second flow paths of a refrigerant distributor forming the heat exchanger communicate with each other. - [
Fig. 10] Fig. 10 conceptually illustrates how refrigerant flows within the refrigerant distributor forming the heat exchanger according toEmbodiment 2. - [
Fig. 11] Fig. 11 illustrates the distribution of flow rate of refrigerant within the refrigerant distributor forming the heat exchanger according toEmbodiment 2. - [
Fig. 12] Fig. 12 is an exploded perspective view of a heat exchanger according to Embodiment 3, conceptually illustrating the configuration of major components of the heat exchanger. - [
Fig. 13] Fig. 13 is a cross-sectional view of the heat exchanger according to Embodiment 3, conceptually illustrating where first and second flow paths of a refrigerant distributor forming the heat exchanger communicate with each other. - [
Fig. 14] Fig. 14 conceptually illustrates how refrigerant flows within the refrigerant distributor forming the heat exchanger according to Embodiment 3. - [
Fig. 15] Fig. 15 illustrates the distribution of flow rate of refrigerant within the refrigerant distributor forming the heat exchanger according to Embodiment 3. - [
Fig. 16] Fig. 16 is an exploded perspective view of a heat exchanger according to Embodiment 4, conceptually illustrating the configuration of major components of the heat exchanger. - [
Fig. 17] Fig. 17 is a cross-sectional view of the heat exchanger according to Embodiment 4, conceptually illustrating where first and second flow paths of a refrigerant distributor forming the heat exchanger communicate with each other. - [
Fig. 18] Fig. 18 conceptually illustrates how refrigerant flows within the refrigerant distributor forming the heat exchanger according to Embodiment 4. - [
Fig. 19] Fig. 19 is an exploded perspective view of a heat exchanger according to Embodiment 5, conceptually illustrating the configuration of major components of the heat exchanger. - [
Fig. 20] Fig. 20 is a conceptual side view of the interior of a refrigerant distributor illustrated inFig. 19 . - [
Fig. 21] Fig. 21 is a cross-sectional view of the heat exchanger according to Embodiment 5, conceptually illustrating where first and second flow paths of the refrigerant distributor forming the heat exchanger communicate with each other. - [
Fig. 22] Fig. 22 is a cross-sectional view of the heat exchanger according to Embodiment 5, conceptually illustrating where first and second flow paths of a modification of the refrigerant distributor forming the heat exchanger communicate with each other. - [
Fig. 23] Fig. 23 conceptually illustrates how refrigerant flows within the refrigerant distributor forming the heat exchanger according to Embodiment 5. Description of Embodiments - A
heat exchanger 100 and a refrigeration cycle apparatus 200 according toEmbodiment 1 will be described below with reference to the drawings or other illustrations. In the figures below includingFig. 1 , the relative dimensions, shapes, and other features of various components may differ from those of the actual components. In the figures below, the same reference signs are used to indicate the same or corresponding elements or features throughout the specification. Although terms representing directions (e.g., "upper", "lower", "right", "left", "front", and "rear") are used as appropriate to facilitate understanding of the present disclosure, such terms are used for illustrative purposes only and not intended to limit the corresponding device or component to any particular placement or orientation. The relative positions of individual components, the directions of extension of individual components, and the directions of arrangement of individual components described herein basically correspond to those when anoutdoor heat exchanger 105 is installed in a usable condition. -
Fig. 1 is a refrigerant circuit diagram illustrating the configuration of the refrigeration cycle apparatus 200 including theheat exchanger 100 according toEmbodiment 1. InFig. 1 , dotted arrows represent the direction in which refrigerant flows in arefrigerant circuit 110 during cooling operation, and solid arrows represent the direction in which refrigerant flows in therefrigerant circuit 110 during heating operation. Reference is made first toFig. 1 to describe the refrigeration cycle apparatus 200 including theheat exchanger 100 described later. - In the following description of the embodiment, an air-conditioning apparatus will be described as an example of the refrigeration cycle apparatus 200. The refrigeration cycle apparatus 200 is used for, for example, refrigeration or air-conditioning purposes, such as for refrigerators or freezers, vending machines, air-conditioning apparatuses, refrigeration apparatuses, or water heaters. The illustrated
refrigerant circuit 110 is given only by way of example, and configurations of circuit elements or other features are not limited to the particular details described below with reference to the embodiment but can be changed or modified as appropriate within the technical scope of the embodiment. - The refrigeration cycle apparatus 200 includes the
refrigerant circuit 110. Therefrigerant circuit 110 includes the following components connected sequentially via a refrigerant pipe; acompressor 101, aflow switching device 102, anindoor heat exchanger 103, apressure reducing device 104, and theoutdoor heat exchanger 105. The refrigeration cycle apparatus 200 includes anoutdoor unit 106, and anindoor unit 107. Theoutdoor unit 106 accommodates the following components: thecompressor 101; theflow switching device 102; theoutdoor heat exchanger 105; thepressure reducing device 104; and anoutdoor fan 108 configured to supply outside air to theoutdoor heat exchanger 105. Theindoor unit 107 accommodates theindoor heat exchanger 103, and anindoor fan 109 configured to supply air to theindoor heat exchanger 103. Theoutdoor unit 106 and theindoor unit 107 are connected with each other via two extension pipes, anextension pipe 111 and anextension pipe 112, which form a portion of the refrigerant pipe. - The
compressor 101 is a piece of fluid machinery that compresses sucked refrigerant and discharges the compressed refrigerant. Theflow switching device 102 is, for example, a four-way valve. Theflow switching device 102 is configured to, under control by a controller (not illustrated), switch the flows of refrigerant between cooling operation and heating operation. Refrigerant is a first heat exchange fluid. - The
indoor heat exchanger 103 is a heat exchanger configured to cause heat exchange to be performed between refrigerant flowing inside theindoor heat exchanger 103, and indoor air supplied by theindoor fan 109. Theindoor heat exchanger 103 functions as a condenser during heating operation, and functions as an evaporator during cooling operation. - The
pressure reducing device 104 is, for example, an expansion valve, and configured to reduce the pressure of refrigerant. A suitable example of thepressure reducing device 104 is an electronic expansion valve whose opening degree is adjusted through control by the controller. - The
outdoor heat exchanger 105 is a heat exchanger configured to cause heat exchange to be performed between refrigerant flowing inside theoutdoor heat exchanger 105, and air supplied by theoutdoor fan 108. Theoutdoor heat exchanger 105 functions as an evaporator during heating operation, and functions as a condenser during cooling operation. Air supplied by theoutdoor fan 108 is an example of a second heat exchange fluid. - The
heat exchanger 100 described later is used as at least one of theoutdoor heat exchanger 105 and theindoor heat exchanger 103. Arefrigerant distributor 150 connected with theheat exchanger 100 is desirably disposed at a location where theheat exchanger 100 receives an increased flow of liquid-phase refrigerant. Specifically, with respect to the flow of refrigerant in therefrigerant circuit 110, therefrigerant distributor 150 is desirably disposed near the inlet of theheat exchanger 100 functioning as an evaporator, that is, near the outlet of theheat exchanger 100 functioning as a condenser. Although therefrigerant distributor 150 is depicted inFig. 1 as being used for both of the twoheat exchangers 100 including theindoor heat exchanger 103 and theoutdoor heat exchanger 105, therefrigerant distributor 150 may be used for only one of the twoheat exchangers 100 including theindoor heat exchanger 103 and theoutdoor heat exchanger 105. - Reference is now made to
Fig. 1 to describe an example of how the refrigeration cycle apparatus 200 operates. During heating operation of the refrigeration cycle apparatus 200, high-pressure and high-temperature refrigerant in a gaseous state discharged from thecompressor 101 flows via theflow switching device 102 into theindoor heat exchanger 103, where the refrigerant condenses through heat exchange with air supplied by theindoor fan 109. The condensed refrigerant changes into a high-pressure liquid state, and then leaves theindoor heat exchanger 103. The resulting refrigerant is turned into a low-pressure, two-phase gas-liquid state by thepressure reducing device 104. The low-pressure refrigerant in the two-phase gas-liquid state flows into theoutdoor heat exchanger 105, where the refrigerant evaporates through heat exchange with air supplied by theoutdoor fan 108. The evaporated refrigerant changes into a low-pressure gaseous state before being sucked into thecompressor 101. During heating operation, if the pressure saturation temperature of theoutdoor heat exchanger 105 is lower than or equal to the dew-point temperature of outdoor air and lower than or equal to the freezing point of water, frost forms on theoutdoor heat exchanger 105. - During cooling operation of the refrigeration cycle apparatus 200, refrigerant flows in the
refrigerant circuit 110 in a direction opposite to the direction of flow during heating operation. That is, during cooling operation of the refrigeration cycle apparatus 200, high-pressure and high-temperature refrigerant in a gaseous state discharged from thecompressor 101 flows via theflow switching device 102 into theoutdoor heat exchanger 105, where the refrigerant condenses through heat exchange with air supplied by theoutdoor fan 108. The condensed refrigerant changes into a high-pressure liquid state, and then leaves theoutdoor heat exchanger 105. The resulting refrigerant is then turned into a low-pressure, two-phase gas-liquid state by thepressure reducing device 104. The low-pressure refrigerant in the two-phase gas-liquid state flows into theindoor heat exchanger 103, where the refrigerant evaporates through heat exchange with air supplied by theindoor fan 109. The evaporated refrigerant changes into a low-pressure gaseous state before being sucked into thecompressor 101. -
Fig. 2 is a side view of theheat exchanger 100 according toEmbodiment 1, conceptually illustrating the configuration of major components of theheat exchanger 100.Fig. 3 is an exploded perspective view of theheat exchanger 100 according toEmbodiment 1, conceptually illustrating the configuration of major components of theheat exchanger 100. Reference is now made toFigs. 2 and3 to describe theheat exchanger 100 according toEmbodiment 1. A hatched arrow F inFig. 2 represents the direction of refrigerant flow in a firstflow path portion 15 of therefrigerant distributor 150. If therefrigerant distributor 150 is used for the refrigeration cycle apparatus 200, therefrigerant distributor 150 is connected with an end of each ofheat transfer tubes 70 that is an end through which refrigerant enters theheat transfer tube 70 when theheat exchanger 100 operates as an evaporator. - As illustrated in
Fig. 2 , theheat exchanger 100 includes multipleheat transfer tubes 70 configured to circulate refrigerant, and therefrigerant distributor 150 connected with one end of each of theheat transfer tubes 70 in a direction in which the tube path of theheat transfer tube 70 extends. Theheat exchanger 100 also includes arefrigerant inflow tube 60 attached to a lower portion of therefrigerant distributor 150. - The
heat transfer tubes 70 are arranged at intervals in a first direction (Z-axis direction), and configured to circulate refrigerant in a second direction (X-axis direction) interesting the first direction (Z-axis direction). Theheat transfer tubes 70 are flat tubes. Although theheat transfer tubes 70 will be described below as flat tubes, theheat transfer tubes 70 may not necessarily be flat tubes but may be, for example, circular tubes. - For the
heat exchanger 100, the direction of arrangement of theheat transfer tubes 70, and the direction of extension of therefrigerant distributor 150 are each defined as a first direction (Z-axis direction). That is, the first direction is the direction in which theheat transfer tubes 70 are arranged. For theheat exchanger 100, the direction of arrangement of theheat transfer tubes 70, which is the first direction (Z-axis direction), is defined as the up-down direction. The up-down direction is, for example, the vertical direction. However, the direction of arrangement of theheat transfer tubes 70, which is defined as the first direction (Z-axis direction), may not necessarily be the up-down direction or the vertical direction. Alternatively, the direction of arrangement of theheat transfer tubes 70 may be a direction inclined relative to the vertical direction, or may be the horizontal direction. - For the
heat exchanger 100, the direction in which the tube paths of theheat transfer tubes 70 extend is defined as a second direction (X-axis direction). The tube paths of theheat transfer tubes 70 representrefrigerant passages 72 described later (seeFig. 4 ). Accordingly, the second direction (X-axis direction) is also the direction of refrigerant flow through the tube paths of theheat transfer tubes 70. For theheat exchanger 100, the direction in which the tube paths of theheat transfer tubes 70 extend, which is the second direction (X-axis direction), is defined as the horizontal direction. However, the direction in which the tube paths of theheat transfer tubes 70 extend, which is defined as the second direction (X-axis direction), may not necessarily be the horizontal direction. Alternatively, the direction in which the tube paths of theheat transfer tubes 70 extend may be a direction inclined relative to the horizontal direction, or may be the up-down direction including the vertical direction. - A
gap 71 through which air flows is defined between two adjacentheat transfer tubes 70.Heat transfer fins 75 may be disposed between two adjacentheat transfer tubes 70 as illustrated inFig. 2 . A portion of theheat exchanger 100 may have theheat transfer fins 75 each serving as a heat transfer facilitating part, and a portion of theheat exchanger 100 may have a region where adjacentheat transfer tubes 70 are not connected with each other by a heat transfer facilitating part. - Adjacent
heat transfer tubes 70 may have noheat transfer fin 75, and may not be connected with each other by such a heat transfer facilitating part. A heat transfer facilitating part is a part used to facilitate heat transfer. An exemplary heat transfer facilitating part is a plate fin such as theheat transfer fin 75, or a corrugated fin. Accordingly, theoutdoor heat exchanger 105 may be implemented as a so-called finless heat exchanger. - If the
heat exchanger 100 functions as an evaporator for the refrigeration cycle apparatus 200, in each of theheat transfer tubes 70, refrigerant flows through each tube path inside theheat transfer tube 70 from one end to the other end in the direction in which the tube path extends. If theheat exchanger 100 functions as a condenser for the refrigeration cycle apparatus 200, in each of theheat transfer tubes 70, refrigerant flows through each tube path inside theheat transfer tube 70 from the other end to the one end in the direction in which the tube path extends. -
Fig. 4 illustrates, in cross-section, the configuration of eachheat transfer tube 70 forming theheat exchanger 100 according toEmbodiment 1.Fig. 4 illustrates a cross-section perpendicular to the direction in which eachheat transfer tube 70 extends. As illustrated inFig. 4 , eachheat transfer tube 70 has a cross-sectional shape that is flattened in one direction, such as an oval shape. - Each
heat transfer tube 70 has afirst side end 70a and asecond side end 70b, and a pair offlat surfaces Fig. 4 , thefirst side end 70a is connected with one end of theflat surface 70c and with one end of theflat surface 70d. In the above-mentioned cross-sectional view, thesecond side end 70b is connected with the other end of theflat surface 70c and with the other end of theflat surface 70d. - The
first side end 70a is a side end located upstream, that is, at the leading edge with respect to the flow of air passing through the heat exchanger. Thesecond side end 70b is a side end located downstream, that is, at the trailing edge with respect to the flow of air passing through the heat exchanger. In the following description, a direction perpendicular to the direction of extension of eachheat transfer tube 70 and along theflat surface 70c and theflat surface 70d is sometimes referred to as long-axis direction of theheat transfer tube 70. - Each
heat transfer tube 70 includes multiplerefrigerant passages 72 arranged in the long-axis direction between thefirst side end 70a and thesecond side end 70b. Eachheat transfer tube 70 is a flat multi-port tube with multiplerefrigerant passages 72 arranged in the direction of air flow and through which refrigerant passes. Each of therefrigerant passages 72 extends in parallel to the direction of extension of theheat transfer tubes 70. - With reference back to
Figs. 2 and3 , therefrigerant distributor 150 will be described below. Therefrigerant distributor 150 has abody 151 extending in the first direction (Z-axis direction). Thebody 151 of therefrigerant distributor 150 is connected with one end of each of theheat transfer tubes 70. Therefrigerant distributor 150 distributes refrigerant to each of theheat transfer tubes 70 connected with thebody 151. - The
body 151 of therefrigerant distributor 150 is disposed in the direction of arrangement of theheat transfer tubes 70 such that thebody 151 extends in the up-down direction. Thebody 151 has a distribution flow path extending in the first direction and defined inside thebody 151 to distribute refrigerant to each of theheat transfer tubes 70. Thebody 151 of therefrigerant distributor 150 has arefrigerant inlet 18 that receives therefrigerant inflow tube 60 inserted into therefrigerant inlet 18, and multiple insertion holes 31 that each receive the corresponding one of theheat transfer tubes 70 inserted into theinsertion hole 31. - The
refrigerant inlet 18 is located at or near oneend 151a of thebody 151 in the first direction. The insertion holes 31 are defined in a side of thebody 151 that is connected with theheat transfer tubes 70. The insertion holes 31 are arranged at intervals in the first direction (Z-axis direction) in one-to-one correspondence to theheat transfer tubes 70. - The
body 151 of therefrigerant distributor 150 includes a first plate-shapedpart 10, a second plate-shapedpart 20, and a third plate-shapedpart 30. The first plate-shapedpart 10, the second plate-shapedpart 20, and the third plate-shapedpart 30 are each made of a flat metal plate formed into a strip elongated in one direction. The respective outer edges of the first plate-shapedpart 10, the second plate-shapedpart 20, and the third plate-shapedpart 30 have identical contours. The first plate-shapedpart 10, the second plate-shapedpart 20, and the third plate-shapedpart 30 are each disposed with the direction of its plate thickness being parallel to the direction in which the tube paths of theheat transfer tubes 70 extend, that is, with its plate plane being perpendicular to the direction in which the tube paths of theheat transfer tubes 70 extend. - In the
body 151 of therefrigerant distributor 150, the first plate-shapedpart 10, the second plate-shapedpart 20, and the third plate-shapedpart 30 are stacked in this order from the farthest to the closest to theheat transfer tubes 70. In thebody 151, the first plate-shapedpart 10 is located farthest to theheat transfer tubes 70, and the third plate-shapedpart 30 is located closest to theheat transfer tubes 70. - The second plate-shaped
part 20 is disposed between the first plate-shapedpart 10 and theheat transfer tubes 70, and adjacent to the first plate-shapedpart 10 and the third plate-shapedpart 30. The third plate-shapedpart 30 is disposed between the second plate-shapedpart 20 and theheat transfer tubes 70, and adjacent to the second plate-shapedpart 20. The third plate-shapedpart 30 is connected with one end of each of theheat transfer tubes 70. - Each adjacent two of the first plate-shaped
part 10, the second plate-shapedpart 20, and the third plate-shapedpart 30 are joined to each other by brazing. The first plate-shapedpart 10, the second plate-shapedpart 20, and the third plate-shapedpart 30 are each disposed with its longitudinal direction being aligned with the first direction (Z-axis direction). -
Fig. 5 is a cross-sectional view of theheat exchanger 100 according toEmbodiment 1, conceptually illustrating where first and second flow paths of therefrigerant distributor 150 forming theheat exchanger 100 communicate with each other. The direction of plate thickness of each of the first plate-shapedpart 10, the second plate-shapedpart 20, and the third plate-shapedpart 30 is the up-down direction inFig. 5 , which coincides with the direction in which the tube paths of theheat transfer tubes 70 extend. The lateral direction of each of the first plate-shapedpart 10, the second plate-shapedpart 20, and the third plate-shapedpart 30 is the left-right direction inFig. 5 , which coincides with the long-axis direction of eachheat transfer tube 70. The configuration of thebody 151 of therefrigerant distributor 150 will be further described below with reference toFigs. 3 and5 . - As illustrated in
Figs. 3 and5 , the first plate-shapedpart 10 has the firstflow path portion 15 that bulges away from theheat transfer tubes 70. The firstflow path portion 15 is tubular in shape, with a space defined inside its bulge. Although the first plate-shapedpart 10 and the firstflow path portion 15 of therefrigerant distributor 150 are formed as an integral component, the first plate-shapedpart 10 and the firstflow path portion 15 may be formed as separate components. - The first
flow path portion 15 extends in the longitudinal direction of the first plate-shapedpart 10 from one longitudinal end of the first plate-shapedpart 10 to the other longitudinal end. The firstflow path portion 15 has the shape of a semicylinder. The firstflow path portion 15 is closed at both ends in the direction of extension of the firstflow path portion 15. When viewed in cross-section perpendicular to the first direction (Z-axis direction), the firstflow path portion 15 has a semicircular shape, a semielliptical shape, or a semioval shape. However, the cross-sectional shape of the firstflow path portion 15 may not necessarily be semicircular, semielliptical, or semioval, but may be, for example, rectangular. - The first plate-shaped
part 10 has aflat plate portion 11a and aflat plate portion 11b formed in the shape of a flat plate and located across the firstflow path portion 15 from each other. Theflat plate portion 11a and theflat plate portion 11b each extend in the longitudinal direction of the first plate-shapedpart 10 from one longitudinal end of the first plate-shapedpart 10 to the other longitudinal end. In other words, the firstflow path portion 15 is located between theflat plate portion 11a and theflat plate portion 11b, and bulges relative to theflat plate portion 11a and theflat plate portion 11b in a direction opposite to the location of theheat transfer tubes 70. The firstflow path portion 15 is open on its side near theheat transfer tubes 70. In the following description, theflat plate portion 11a and theflat plate portion 11b will be sometimes generically referred to asflat plate portion 11. - The first
flow path portion 15 has, in its inside, amain flow path 15a extending in the up-down direction along the length of the first plate-shapedpart 10. Themain flow path 15a corresponds to a first flow path of therefrigerant distributor 150. Themain flow path 15a serving as the first flow path is connected with therefrigerant inflow tube 60, which is connected with therefrigerant inlet 18. Themain flow path 15a extends in the first direction (Z-axis direction) in which theheat transfer tubes 70 are arranged. - When viewed in the direction of plate thickness of the first plate-shaped
part 10, themain flow path 15a serving as the first flow path extends while intersecting each of theheat transfer tubes 70. Themain flow path 15a serving as the first flow path communicates with the tube paths of theheat transfer tubes 70 via distribution holes 26 described later, which are provided in the second plate-shapedpart 20. - When viewed in cross-section perpendicular to the first direction (Z-axis direction), the
main flow path 15a has a semicircular shape, a semielliptical shape, or a semioval shape. That is, themain flow path 15a is a space having the shape of a semicircular cylinder, a semielliptical cylinder, or a semioval cylinder. However, the cross-sectional shape of themain flow path 15a may not necessarily be semicircular, semielliptical, or semioval, but may be, for example, rectangular. - As described above, the
main flow path 15a serving as the first flow path is formed so as to extend in the first direction (Z-axis direction), communicates with theheat transfer tubes 70, and is connected, at a lower end 15a2 in the first direction, with therefrigerant inflow tube 60 configured to cause refrigerant to flow into therefrigerant distributor 150. Two-phase gas-liquid refrigerant entering themain flow path 15a via therefrigerant inflow tube 60 flows upward in themain flow path 15a so as to travel from the oneend 151a of thebody 151 toward theother end 151b, and is distributed to each of theheat transfer tubes 70. - The lower end of the first
flow path portion 15 is connected with therefrigerant inflow tube 60. Themain flow path 15a, and the internal space of therefrigerant inflow tube 60 communicate with each other. Therefrigerant inflow tube 60 is configured to cause two-phase gas-liquid refrigerant to flow into themain flow path 15a when theheat exchanger 100 acts as an evaporator. The location of connection between therefrigerant inflow tube 60 and the firstflow path portion 15 corresponds to therefrigerant inlet 18 through which refrigerant flows into therefrigerant distributor 150. When theheat exchanger 100 functions as a condenser, liquid refrigerant flows downward in themain flow path 15a, and exits theheat exchanger 100 through therefrigerant inflow tube 60. - The second plate-shaped
part 20 has asub-flow path 25, and the distribution holes 26. A direction intersecting a plane P parallel to the first direction (Z-axis direction) and the second direction (X-axis direction) is defined as a third direction. The third direction includes the Y-axis direction. With respect to the third direction (Y-axis direction), eachdistribution hole 26 is located in the vicinity of the middle of the second plate-shapedpart 20, and thesub-flow path 25 is located in the vicinity of each end of the second plate-shapedpart 20. That is, with respect to the third direction (Y-axis direction), eachdistribution hole 26 is located in the vicinity of the middle of the second plate-shapedpart 20, and thesub-flow path 25 is disposed beside both sides of thedistribution hole 26. Thesub-flow path 25 and the distribution holes 26 of the second plate-shapedpart 20 may not necessarily be located at the above-mentioned positions in the second plate-shapedpart 20. A part of thesub-flow path 25 disposed beside one side of the distribution holes 26, and a part of thesub-flow path 25 disposed beside the other side of the distribution holes 26 may communicate with each other at least in their respective one end portions in the first direction. - The
sub-flow path 25 is provided in the second plate-shapedpart 20 so as to extend in the first direction (Z-axis direction). That is, thesub-flow path 25 is provided along the length of the second plate-shapedpart 20 so as to extend in the up-down direction. Thesub-flow path 25 corresponds to a second flow path of therefrigerant distributor 150. Thesub-flow path 25 serving as the second flow path is provided in thebody 151 of therefrigerant distributor 150 such that thesub-flow path 25 is connected at both ends with themain flow path 15a serving as the first flow path. Thesub-flow path 25 defines a refrigerant flow path that provides communication between an upper end 15a1 of themain flow path 15a and the lower end 15a2 such that refrigerant that has reached the upper end 15a1 of themain flow path 15a is returned to the lower end 15a2 where therefrigerant inlet 18 is located. In thebody 151 of therefrigerant distributor 150, themain flow path 15a and thesub-flow path 25 define a circulation flow path for refrigerant. - The
body 151 of therefrigerant distributor 150 has themain flow path 15a and thesub-flow path 25 that are defined inside thebody 151 and through which refrigerant flows. As described above, themain flow path 15a corresponds to the first flow path, and thesub-flow path 25 corresponds to the second flow path. Thesub-flow path 25 serving as the second flow path is located in the third direction relative to themain flow path 15a serving as the first flow path. That is, themain flow path 15a and thesub-flow path 25 are located upstream and downstream in the direction of airflow created by theoutdoor fan 108 or theindoor fan 109 illustrated inFig. 1 . - The
sub-flow path 25 has amiddle portion 25a, aninlet portion 25b, and anoutlet portion 25c. Themiddle portion 25a defines a flow path extending in the first direction (Z-axis direction). Theinlet portion 25b is located at one end 25a1 of themiddle portion 25a in the first direction (Z-axis direction). Theoutlet portion 25c is located at the other end 25a2 of themiddle portion 25a in the first direction (Z-axis direction). Theinlet portion 25b and theoutlet portion 25c are each provided in thebody 151 of therefrigerant distributor 150 as a flow path extending in the third direction (Y-axis direction). - In the direction of stacking of the first plate-shaped
part 10, the second plate-shapedpart 20, and the third plate-shapedpart 30, themiddle portion 25a of thesub-flow path 25 is sandwiched between theflat plate portion 11 of the first plate-shapedpart 10, and aflat plate portion 34 of the third plate-shapedpart 30. - Opposite ends of the
sub-flow path 25 are defined by theinlet portion 25b and theoutlet portion 25c. In the direction of stacking of the first plate-shapedpart 10, the second plate-shapedpart 20, and the third plate-shapedpart 30, theinlet portion 25b and theoutlet portion 25c are sandwiched between the firstflow path portion 15, and theflat plate portion 34 of the third plate-shapedpart 30. Accordingly, theinlet portion 25b and theoutlet portion 25c communicate with themain flow path 15a, which is the first flow path defined by the firstflow path portion 15. By contrast, themiddle portion 25a of thesub-flow path 25 does not communicate with themain flow path 15a serving as the first flow path. - In the
body 151 of therefrigerant distributor 150, thesub-flow path 25 serving as the second flow path has theinlet portion 25b and theoutlet portion 25c. Thesub-flow path 25 is thus connected at its both ends with themain flow path 15a serving as the first flow path. More specifically, in thebody 151 of therefrigerant distributor 150, theinlet portion 25b of thesub-flow path 25 serving as the second flow path communicates with the upper end 15a1 of themain flow path 15a. In thebody 151 of therefrigerant distributor 150, theoutlet portion 25c of thesub-flow path 25 serving as the second flow path communicates with the lower end 15a2 of themain flow path 15a. - Refrigerant passes through the
inlet portion 25b when flowing from themain flow path 15a serving as the first flow path into thesub-flow path 25 serving as the second flow path. That is, refrigerant flows into theinlet portion 25b from themain flow path 15a serving as the first flow path. Refrigerant passes through theoutlet portion 25c when flowing from thesub-flow path 25 serving as the second flow path into themain flow path 15a serving as the first flow path. That is, refrigerant exits through theoutlet portion 25c into themain flow path 15a serving as the first flow path. In thebody 151 of therefrigerant distributor 150, thesub-flow path 25 serving as the second flow path does not communicate withinsertion holes 31, which will be described later, of the third plate-shapedpart 30. - The second plate-shaped
part 20 has multiple distribution holes 26 each defining a circular opening. The distribution holes 26 define flow paths between themain flow path 15a and theheat transfer tubes 70, and are configured to distribute refrigerant to each of theheat transfer tubes 70. Each of the distribution holes 26 is a through-hole extending through the second plate-shapedpart 20 in the direction of plate thickness of the second plate-shapedpart 20. The distribution holes 26 are arranged in the first direction (Z-axis direction), which coincides with the longitudinal direction of the second plate-shapedpart 20. The distribution holes 26 each define a through-hole extending through the second plate-shapedpart 20. The distribution holes 26 are disposed in one-to-one correspondence to theheat transfer tubes 70. - Although the opening defined by each
distribution hole 26 is described above as having a circular shape, the opening may not necessarily have a circular shape. Alternatively, for example, the opening may have a semicircular shape, a semielliptical shape, a semioval shape, or a rectangular shape. The distribution holes 26 define flow paths with the same cross-sectional area. However, the distribution holes 26 may not necessarily define flow paths with the same cross-sectional area, but may define flow paths with different cross-sectional areas. - Although the second plate-shaped
part 20 of thebody 151 of therefrigerant distributor 150 according toEmbodiment 1 is described above as having multiple distribution holes 26, the second plate-shapedpart 20 may have only asingle distribution hole 26. In this case, thesingle distribution hole 26 extends in the first direction (Z-axis direction) in such a way that thedistribution hole 26 corresponds to multipleheat transfer tubes 70. - When viewed in the direction of plate thickness of the second plate-shaped
part 20, each of the distribution holes 26 overlaps themain flow path 15a of the first plate-shapedpart 10. When viewed in the direction of plate thickness of the second plate-shapedpart 20, each of the distribution holes 26 overlaps the corresponding one of the insertion holes 31, which will be described later, of the third plate-shapedpart 30. Further, when viewed in the direction of plate thickness of the second plate-shapedpart 20, each of the distribution holes 26 overlaps the corresponding one of theheat transfer tubes 70. Therefore, in the direction of stacking of the first plate-shapedpart 10, the second plate-shapedpart 20, and the third plate-shapedpart 30, the distribution holes 26 are located between theheat transfer tubes 70, and themain flow path 15a serving as the first flow path. Themain flow path 15a of the first plate-shapedpart 10, and each of theheat transfer tubes 70 communicate with each other via the corresponding one of the distribution holes 26. - The second plate-shaped
part 20 has a blockingportion 24 in the form of a flat plate. When viewed in the direction of plate thickness of the second plate-shapedpart 20, the blockingportion 24 partially overlaps themain flow path 15a of the first plate-shapedpart 10. The blockingportion 24 serves to prevent themain flow path 15a and each of theheat transfer tubes 70 from communicating with each other directly rather than via the correspondingdistribution hole 26. - The third plate-shaped
part 30 has multiple insertion holes 31 each configured to receive one end of the corresponding one of theheat transfer tubes 70 inserted into theinsertion hole 31. Each of the insertion holes 31 is a through-hole extending through the third plate-shapedpart 30 in the direction of plate thickness of the third plate-shapedpart 30. - The insertion holes 31 are arranged in parallel in the up-down direction along the length of the third plate-shaped
part 30. The insertion holes 31 are provided independently of each other in one-to-one correspondence to theheat transfer tubes 70. Eachinsertion hole 31 defines an opening with a flattened shape that conforms to the outer circumferential shape of the correspondingheat transfer tube 70. The entire circumference of the opening edge of eachinsertion hole 31 is joined by brazing to the outer circumferential surface of the correspondingheat transfer tube 70. - The third plate-shaped
part 30 has theflat plate portion 34 in the form of a flat plate. Theflat plate portion 34 corresponds to a portion of the third plate-shapedpart 30 that, when viewed in the direction of plate thickness of the third plate-shapedpart 30, overlaps thesub-flow path 25 of the second plate-shapedpart 20. Thesub-flow path 25 serving as the second flow path is blocked by theflat plate portion 34 and theflat plate portion 11 in the second direction (X-axis direction). - In the
body 151 of therefrigerant distributor 150, themain flow path 15a serving as the first flow path, and each end of thesub-flow path 25 serving as the second flow path overlap each other in the direction of stacking of the first plate-shapedpart 10, the second plate-shapedpart 20, and the third plate-shapedpart 30. In thebody 151 of therefrigerant distributor 150, themain flow path 15a serving as the first flow path, eachdistribution hole 26, and eachinsertion hole 31 overlap each other in the direction of stacking of the first plate-shapedpart 10, the second plate-shapedpart 20, and the third plate-shapedpart 30. -
Fig. 6 conceptually illustrates how refrigerant flows within therefrigerant distributor 150 forming theheat exchanger 100 according toEmbodiment 1. Reference is now made to an example of how therefrigerant distributor 150 according toEmbodiment 1 operates when theheat exchanger 100 functions as an evaporator for the refrigeration cycle apparatus 200. - When the refrigeration cycle apparatus 200 is in heating operation, refrigerant flows into the
refrigerant distributor 150 in a two-phase gas-liquid state. The two-phase gas-liquid refrigerant flows into thebody 151 through therefrigerant inflow tube 60 illustrated inFigs. 2 and6 . Then, as represented by an arrow UF inFig. 6 , the refrigerant travels vertically upward in themain flow path 15a, which is defined in the first plate-shapedpart 10, from the oneend 151a toward theother end 151b. As the refrigerant travels vertically upward, the refrigerant passes through eachdistribution hole 26 of the second plate-shapedpart 20 and then through eachinsertion hole 31 of the third plate-shapedpart 30 for distribution to eachheat transfer tube 70. - Refrigerant that accumulates in an upper portion of the
main flow path 15a flows into theinlet portion 25b defined in the second plate-shapedpart 20 and communicating with the upper end 15a1 of themain flow path 15a. At this time, as represented by an arrow OF, the refrigerant flows outward in the third direction from themain flow path 15a serving as the first flow path toward thesub-flow path 25 serving as the second flow path. Then, as represented by an arrow DF, the refrigerant entering through theinlet portion 25b of thesub-flow path 25 flows downward in the direction of gravity in themiddle portion 25a of thesub-flow path 25 defined in the second plate-shapedpart 20. - Upon reaching the lower end of the
middle portion 25a of thesub-flow path 25, the refrigerant exits thesub-flow path 25 into themain flow path 15a through theoutlet portion 25c communicating with the lower end 15a2 of themain flow path 15a. At this time, as represented by an arrow IF, the refrigerant flows inward in the third direction from thesub-flow path 25 serving as the second flow path toward themain flow path 15a serving as the first flow path. After exiting through theoutlet portion 25c into themain flow path 15a, the exiting refrigerant, together with the refrigerant flowing into thebody 151 through therefrigerant inflow tube 60, travels vertically upward in themain flow path 15a, and is distributed to eachheat transfer tube 70. -
Fig. 7 illustrates the distribution of flow rate of refrigerant within therefrigerant distributor 150 forming theheat exchanger 100 according toEmbodiment 1. InFig. 7 , the horizontal axis represents refrigerant flow rate [kg/h], and the vertical axis represents the distance [m] from therefrigerant inlet 18 in the first direction in which theheat transfer tubes 70 are arranged. - In
Fig. 7 , a dotted line A represents the flow rate at which refrigerant flows in themain flow path 15a if nosub-flow path 25 is present, and a solid line B represents the flow rate at which refrigerant flows in themain flow path 15a if thesub-flow path 25 is present. An alternate long and short dash line C represents a case where the flow rate of refrigerant in themain flow path 15a is constant in the up-down direction. If the flow rate of refrigerant in themain flow path 15a is constant in the up-down direction, then the flow rate of refrigerant into each of theheat transfer tubes 70 arranged in the first direction is constant. Accordingly, the closer the flow rate of refrigerant in themain flow path 15a is to the flow rate of refrigerant represented by the alternate long and short dash line C, the more desirable. - As represented by the dotted line A, if the
body 151 is not provided with thesub-flow path 25 serving as the second flow path, liquid refrigerant accumulates in an upper portion of themain flow path 15a serving as the first flow path. This results in comparatively more liquid refrigerant being distributed in the upper portion of themain flow path 15a serving as the first flow path. - By contrast, if the
body 151 is provided with thesub-flow path 25 serving as the second flow path, liquid refrigerant that accumulates in an upper portion of themain flow path 15a returns to a lower portion of themain flow path 15a by way of thesub-flow path 25. Thus, as represented by an arrow MU between the dotted line A and the solid line B, the flow rate of refrigerant decreases in the upper portion of themain flow path 15a as the refrigerant returns to the lower portion of themain flow path 15a. Further, as represented by an arrow MD between the dotted line A and the solid line B, the flow rate of refrigerant increases in the lower portion of themain flow path 15a as the refrigerant returns to the lower portion from the upper portion of themain flow path 15a. Consequently, as represented by the solid line B, the flow rate at which refrigerant flows in themain flow path 15a if thesub-flow path 25 is present is closer to the flow rate represented by the alternate long and short dash line C, than is the flow rate at which refrigerant flows in themain flow path 15a if nosub-flow path 25 is present. Therefore, therefrigerant distributor 150 with thesub-flow path 25 allows for uniform distribution of refrigerant to eachheat transfer tube 70, in comparison to a refrigerant distributor without thesub-flow path 25. - The
heat exchanger 100 includes therefrigerant distributor 150 that includes themain flow path 15a and thesub-flow path 25 through which refrigerant flows. Thesub-flow path 25 serving as the second flow path is formed so as to extend in the first direction (Z-axis direction), with opposite ends thereof being connected with themain flow path 15a serving as the first flow path. Thesub-flow path 25 serving as the second flow path is formed so as to be positioned in the third direction relative to themain flow path 15a serving as the first flow path, when a direction intersecting the plane P parallel to the first direction (Z-axis direction) and the second direction (X-axis direction) is defined as the third direction. The above-mentioned configuration of theheat exchanger 100 helps to prevent or reduce an increase in the size of therefrigerant distributor 150 in the second direction in which refrigerant is circulated, and allows theheat exchanger 100 to be enlarged, within a range of structural constraints, in the second direction in which the tube paths of theheat transfer tubes 70 extend. Therefore, theheat exchanger 100 allows for increased heat transfer surface area of theheat transfer tubes 70, and also allows therefrigerant distributor 150 to be made compact without an increase in the size of therefrigerant distributor 150 in the direction in which the tube paths of theheat transfer tubes 70 extend. - The
heat exchanger 100 allows for increased heat transfer surface area of theheat transfer tubes 70, in comparison to a heat exchanger having first and second flow paths that are provided in the direction in which the tube paths of theheat transfer tubes 70 extend. Theheat exchanger 100 thus allows for improved heat exchange performance, in comparison to a heat exchanger having first and second flow paths that are provided in the direction in which the tube paths of theheat transfer tubes 70 extend. Therefore, theheat exchanger 100 provides improved mitigation of refrigerant maldistribution with respect to changes in refrigerant flow rate or quality that depend on the operating condition of an air-conditioning apparatus. This leads to improved distribution robustness, that is, the ability to accommodate a wider range of refrigerant flow rate or other conditions. - The
heat exchanger 100 has thesub-flow path 25. The presence of thesub-flow path 25 ensures that when an operating condition of the air-conditioning apparatus causes liquid refrigerant to accumulate in an upper portion of themain flow path 15a, the refrigerant is circulated from the upper portion of themain flow path 15a to the lower portion of themain flow path 15a. This helps to prevent or reduce maldistribution of refrigerant. Theheat exchanger 100 including therefrigerant distributor 150 with thesub-flow path 25 thus allows for uniform distribution of refrigerant to eachheat transfer tube 70, in comparison to a heat exchanger that includes a refrigerant distributor without thesub-flow path 25. This results in improved heat exchange performance of theheat exchanger 100 in comparison to a heat exchanger that includes a refrigerant distributor without thesub-flow path 25. - In the
refrigerant distributor 150, in the direction of stacking of the first plate-shapedpart 10, the second plate-shapedpart 20, and the third plate-shapedpart 30, themain flow path 15a and each end of thesub-flow path 25 overlap each other, and themain flow path 15a, eachdistribution hole 26, and eachinsertion hole 31 overlap each other. The above-mentioned configuration of theheat exchanger 100 helps to prevent or reduce an increase in the size of therefrigerant distributor 150 in the second direction in which the tube paths of theheat transfer tubes 70 extend, and allows theheat exchanger 100 to be enlarged, within a range of structural constraints, in the second direction in which the tube paths of theheat transfer tubes 70 extend. Therefore, theheat exchanger 100 allows for increased heat transfer surface area of theheat transfer tubes 70, and also allows therefrigerant distributor 150 to be made compact without an increase in the size of therefrigerant distributor 150 in the direction in which the tube paths of theheat transfer tubes 70 extend. - Opposite ends of the
sub-flow path 25 serving as the second flow path are defined by theinlet portion 25b where refrigerant flows into thesub-flow path 25 from themain flow path 15a serving as the first flow path, and theoutlet portion 25c where refrigerant exits thesub-flow path 25 into themain flow path 15a serving as the first flow path. Theinlet portion 25b and theoutlet portion 25c extend in the third direction. The above-mentioned configuration of theheat exchanger 100 helps to prevent or reduce an increase in the size of therefrigerant distributor 150 in the second direction in which the tube paths of theheat transfer tubes 70 extend, and allows theheat exchanger 100 to be enlarged, within a range of structural constraints, in the second direction in which the tube paths of theheat transfer tubes 70 extend. Therefore, theheat exchanger 100 allows for increased heat transfer surface area of theheat transfer tubes 70, and also allows therefrigerant distributor 150 to be made compact without an increase in the size of therefrigerant distributor 150 in the direction in which the tube paths of theheat transfer tubes 70 extend. - The
sub-flow path 25 serving as the second flow path is disposed beside both sides of the distribution holes 26 in the third direction. The above-mentioned configuration of theheat exchanger 100 helps to prevent or reduce an increase in the size of therefrigerant distributor 150 in the second direction in which the tube paths of theheat transfer tubes 70 extend, and allows theheat exchanger 100 to be enlarged, within a range of structural constraints, in the second direction in which the tube paths of theheat transfer tubes 70 extend. Therefore, theheat exchanger 100 allows for increased heat transfer surface area of theheat transfer tubes 70, and also allows therefrigerant distributor 150 to be made compact without an increase in the size of therefrigerant distributor 150 in the direction in which the tube paths of theheat transfer tubes 70 extend. - Multiple distribution holes 26 are provided in the first direction (Z-axis direction). Each of the distribution holes 26 serves as a restriction hole with high flow resistance in the refrigerant flow path located between the
main flow path 15a, which is the first flow path, and each of theheat transfer tubes 70. When the heat exchanger functions as an evaporator, eachdistribution hole 26 serves as a restriction hole. As a result, the pressure in themain flow path 15a rises, which causes an increase in the differential pressure between themain flow path 15a and eachindividual insertion hole 31. This evens out the differential pressure between themain flow path 15a and the higher positioned insertion holes 31, and the differential pressure between themain flow path 15a and the lower positioned insertion holes 31. As a result, refrigerant in themain flow path 15a is distributed evenly to eachinsertion hole 31, and consequently distributed evenly to eachheat transfer tube 70. -
Fig. 8 is an exploded perspective view of theheat exchanger 100 according toEmbodiment 2, conceptually illustrating the configuration of major components of theheat exchanger 100.Fig. 9 is a cross-sectional view of theheat exchanger 100 according toEmbodiment 2, conceptually illustrating where the first and second flow paths of therefrigerant distributor 150 forming theheat exchanger 100 communicate with each other. Components identical in function and operation to the components described above with reference toEmbodiment 1 are designated by the same reference signs and not described in further detail below. Theheat exchanger 100 according toEmbodiment 2 differs from theheat exchanger 100 according toEmbodiment 1 in that therefrigerant distributor 150 further includes a fourth plate-shapedpart 40 and a fifth plate-shapedpart 50. - The
body 151 of therefrigerant distributor 150 includes the first plate-shapedpart 10, the second plate-shapedpart 20, the third plate-shapedpart 30, the fourth plate-shapedpart 40, and the fifth plate-shapedpart 50. The fourth plate-shapedpart 40 and the fifth plate-shapedpart 50 are each made of a flat metal plate formed into a strip elongated in one direction. The respective outer edges of the first plate-shapedpart 10, the second plate-shapedpart 20, the third plate-shapedpart 30, the fourth plate-shapedpart 40, and the fifth plate-shapedpart 50 have identical contours. The first plate-shapedpart 10, the second plate-shapedpart 20, the third plate-shapedpart 30, the fourth plate-shapedpart 40, and the fifth plate-shapedpart 50 are each disposed with the direction of its plate thickness being parallel to the direction in which the tube paths of theheat transfer tubes 70 extend. That is, the first plate-shapedpart 10, the second plate-shapedpart 20, the third plate-shapedpart 30, the fourth plate-shapedpart 40, and the fifth plate-shapedpart 50 are each disposed with its plate plane being perpendicular to the direction in which the tube paths of theheat transfer tubes 70 extend. - In the
body 151 of therefrigerant distributor 150, the first plate-shapedpart 10, the fourth plate-shapedpart 40, the second plate-shapedpart 20, the fifth plate-shapedpart 50, and the third plate-shapedpart 30 are stacked in this order from the farthest to the closest to theheat transfer tubes 70. In thebody 151, the first plate-shapedpart 10 is located farthest to theheat transfer tubes 70, and the third plate-shapedpart 30 is located closest to theheat transfer tubes 70. - The fourth plate-shaped
part 40 is disposed between the first plate-shapedpart 10 and the second plate-shapedpart 20, and the plate plane of the fourth plate-shapedpart 40 is adjacent to the plate plane of the first plate-shapedpart 10 and the plate plane of the second plate-shapedpart 20. The fifth plate-shapedpart 50 is disposed between the second plate-shapedpart 20 and the third plate-shapedpart 30, and the plate plane of the fifth plate-shapedpart 50 is adjacent to the plate plane of the second plate-shapedpart 20 and the plate plane of the third plate-shapedpart 30. - Adjacent two of the first plate-shaped
part 10, the fourth plate-shapedpart 40, the second plate-shapedpart 20, the fifth plate-shapedpart 50, and the third plate-shapedpart 30 are joined to each other by brazing. The first plate-shapedpart 10, the fourth plate-shapedpart 40, the second plate-shapedpart 20, the fifth plate-shapedpart 50, and the third plate-shapedpart 30 are each disposed with its longitudinal direction being aligned with the first direction (Z-axis direction). - The fourth plate-shaped
part 40 has communication holes 45, and second distribution holes 46. The communication holes 45 are located between themain flow path 15a serving as the first flow path, and each end of thesub-flow path 25. The second distribution holes 46 are located between themain flow path 15a serving as the first flow path, and the second distribution holes 46. The communication holes 45 and the second distribution holes 46 are through-holes. - In the fourth plate-shaped
part 40, twocommunication holes 45 are provided near the oneend 151a, and twocommunication holes 45 are provided near theother end 151b. The communication holes 45 provided near the oneend 151a serve as an outlet through which refrigerant exits thesub-flow path 25 into themain flow path 15a. The communication holes 45 provided near theother end 151b serve as an inlet through which refrigerant flows from themain flow path 15a into thesub-flow path 25. Although eachcommunication hole 45 is depicted inFig. 8 as a through-hole defining a rectangular opening, this is not intended to limit the shape of the opening defined by thecommunication hole 45 to a rectangle. - The communication holes 45 are located between the
main flow path 15a and theinlet portion 25b in the direction of stacking of the first plate-shapedpart 10, the fourth plate-shapedpart 40, the second plate-shapedpart 20, the fifth plate-shapedpart 50, and the third plate-shapedpart 30. The communication holes 45 are also located between themain flow path 15a and theoutlet portion 25c in the direction of stacking of the first plate-shapedpart 10, the fourth plate-shapedpart 40, the second plate-shapedpart 20, the fifth plate-shapedpart 50, and the third plate-shapedpart 30. Therefore, eachcommunication hole 45 provides communication between themain flow path 15a serving as the first flow path and thesub-flow path 25 serving as the second flow path, and serves as a flow path that interconnects themain flow path 15a serving as the first flow path and thesub-flow path 25 serving as the second flow path. - The fourth plate-shaped
part 40 has multiple second distribution holes 46 each defining a circular opening. Eachsecond distribution hole 46 is located in the vicinity of the middle of the fourth plate-shapedpart 40 in the third direction (Y-axis direction). The second distribution holes 46 define flow paths between themain flow path 15a and theheat transfer tubes 70, together with the distribution holes 26 of the second plate-shapedpart 20 and third distribution holes 51, which will be described later, of the fifth plate-shapedpart 50. Eachsecond distribution hole 46 is configured to distribute refrigerant to the correspondingheat transfer tube 70. - Each of the second distribution holes 46 is a through-hole extending through the fourth plate-shaped
part 40 in the direction of plate thickness of the fourth plate-shapedpart 40. The second distribution holes 46 are arranged in the first direction (Z-axis direction), which coincides with the longitudinal direction of the fourth plate-shapedpart 40. The second distribution holes 46 each define a through-hole extending through the fourth plate-shapedpart 40, and are disposed in one-to-one correspondence to theheat transfer tubes 70. The second distribution holes 46 are provided in one-to-one correspondence to the distribution holes 26 of the second plate-shapedpart 20. Further, the second distribution holes 46 are provided in one-to-one correspondence to the third distribution holes 51, which will be described later, of the fifth plate-shapedpart 50. - Although the opening defined by each
second distribution hole 46 is described above as having a circular shape, the opening may not necessarily have a circular shape. Alternatively, for example, the opening may have a semicircular shape, a semielliptical shape, a semioval shape, or a rectangular shape. The second distribution holes 46 define flow paths with the same cross-sectional area. However, the second distribution holes 46 may not necessarily define flow paths with the same cross-sectional area, but may define flow paths with different cross-sectional areas. - Although the fourth plate-shaped
part 40 of thebody 151 of therefrigerant distributor 150 according toEmbodiment 2 is described above as having multiple second distribution holes 46, the fourth plate-shapedpart 40 may have only a singlesecond distribution hole 46. In this case, the singlesecond distribution hole 46 is formed so as to extend in the first direction (Z-axis direction) such that thesecond distribution hole 46 corresponds to multipleheat transfer tubes 70. - When viewed in the direction of plate thickness of the fourth plate-shaped
part 40, each of the second distribution holes 46 overlaps themain flow path 15a of the first plate-shapedpart 10. When viewed in the direction of plate thickness of the fourth plate-shapedpart 40, each of the second distribution holes 46 overlaps the corresponding one of the distribution holes 26 of the second plate-shapedpart 20. When viewed in the direction of plate thickness of the fourth plate-shapedpart 40, each of the second distribution holes 46 overlaps the corresponding one of the third distribution holes 51 of the fifth plate-shapedpart 50. When viewed in the direction of plate thickness of the fourth plate-shapedpart 40, each of the second distribution holes 46 overlaps the corresponding one of the insertion holes 31 of the third plate-shapedpart 30. When viewed in the direction of plate thickness of the fourth plate-shapedpart 40, each of the second distribution holes 46 overlaps the corresponding one of theheat transfer tubes 70. - Therefore, in the direction of stacking of the first plate-shaped
part 10, the fourth plate-shapedpart 40, the second plate-shapedpart 20, the fifth plate-shapedpart 50, and the third plate-shapedpart 30, the second distribution holes 46 are located between theheat transfer tubes 70, and themain flow path 15a serving as the first flow path. Themain flow path 15a of the first plate-shapedpart 10, and each of theheat transfer tubes 70 communicate with each other via the corresponding one of the second distribution holes 46. - The fourth plate-shaped
part 40 has a blockingportion 44 in the form of a flat plate. When viewed in the direction of plate thickness of the fourth plate-shapedpart 40, the blockingportion 44 partially overlaps themain flow path 15a of the first plate-shapedpart 10. The blockingportion 44 serves to prevent themain flow path 15a and each of theheat transfer tubes 70 from communicating with each other directly rather than via the correspondingsecond distribution hole 46. - The blocking
portion 44 covers a portion of thesub-flow path 25 from a side of thesub-flow path 25 that is located near the first plate-shapedpart 10. The blockingportion 44 covers at least themiddle portion 25a of thesub-flow path 25 from a side of thesub-flow path 25 that is located near the first plate-shapedpart 10. The blockingportion 44 constitutes a portion of the tube path defining thesub-flow path 25. - The fifth plate-shaped
part 50 has the third distribution holes 51 located between the distribution holes 26 and the insertion holes 31. Eachthird distribution hole 51 is a through-hole. - The fifth plate-shaped
part 50 has multiple third distribution holes 51 each defining a circular opening. Eachthird distribution hole 51 is located in the vicinity of the middle of the fifth plate-shapedpart 50 in the third direction (Y-axis direction). The third distribution holes 51 define flow paths between themain flow path 15a and theheat transfer tubes 70, together with the distribution holes 26 of the second plate-shapedpart 20 and the second distribution holes 46 of the fourth plate-shapedpart 40. Eachthird distribution hole 51 is configured to distribute refrigerant to the correspondingheat transfer tube 70. - Each of the third distribution holes 51 is a through-hole extending through the fifth plate-shaped
part 50 in the direction of plate thickness of the fifth plate-shapedpart 50. The third distribution holes 51 are arranged in the first direction (Z-axis direction), which coincides with the longitudinal direction of the fifth plate-shapedpart 50. The third distribution holes 51 each define a through-hole extending through the fifth plate-shapedpart 50, and are disposed in one-to-one correspondence to theheat transfer tubes 70. The third distribution holes 51 are provided in one-to-one correspondence to the distribution holes 26 of the second plate-shapedpart 20. Further, the third distribution holes 51 are provided in one-to-one correspondence to the second distribution holes 46 defined in the fourth plate-shapedpart 40. - Although the opening defined by each
third distribution hole 51 is described above as having a circular shape, the opening may not necessarily have a circular shape. Alternatively, for example, the opening may have a semicircular shape, a semielliptical shape, a semioval shape, or a rectangular shape. The third distribution holes 51 define flow paths with the same cross-sectional area. However, the third distribution holes 51 may not necessarily define flow paths with the same cross-sectional area, but may define flow paths with different cross-sectional areas. - Although the fifth plate-shaped
part 50 of thebody 151 of therefrigerant distributor 150 according toEmbodiment 1 is described above as having multiple third distribution holes 51, the fifth plate-shapedpart 50 may have only a singlethird distribution hole 51. In this case, the singlethird distribution hole 51 is formed so as to extend in the first direction (Z-axis direction) such that thethird distribution hole 51 corresponds to multipleheat transfer tubes 70. - When viewed in the direction of plate thickness of the fifth plate-shaped
part 50, each of the third distribution holes 51 overlaps themain flow path 15a of the first plate-shapedpart 10. When viewed in the direction of plate thickness of the fifth plate-shapedpart 50, each of the third distribution holes 51 overlaps the corresponding one of the distribution holes 26 of the second plate-shapedpart 20. When viewed in the direction of plate thickness of the fifth plate-shapedpart 50, each of the third distribution holes 51 overlaps the corresponding one of the second distribution holes 46 of the fourth plate-shapedpart 40. When viewed in the direction of plate thickness of the fifth plate-shapedpart 50, each of the third distribution holes 51 overlaps the corresponding one of the insertion holes 31 of the third plate-shapedpart 30. When viewed in the direction of plate thickness of the fifth plate-shapedpart 50, each of the third distribution holes 51 overlaps the corresponding one of theheat transfer tubes 70. - Therefore, in the direction of stacking of the first plate-shaped
part 10, the fourth plate-shapedpart 40, the second plate-shapedpart 20, the fifth plate-shapedpart 50, and the third plate-shapedpart 30, the third distribution holes 51 are located between theheat transfer tubes 70, and themain flow path 15a serving as the first flow path. Themain flow path 15a of the first plate-shapedpart 10, and each of theheat transfer tubes 70 communicate with each other via the corresponding one of the third distribution holes 51. - The fifth plate-shaped
part 50 has a blockingportion 53 in the form of a flat plate. When viewed in the direction of plate thickness of the fifth plate-shapedpart 50, the blockingportion 53 partially overlaps themain flow path 15a of the first plate-shapedpart 10. The blockingportion 53 serves to prevent themain flow path 15a and each of theheat transfer tubes 70 from communicating with each other directly rather than via the correspondingthird distribution hole 51. - The blocking
portion 53 covers a portion of thesub-flow path 25 from a side of thesub-flow path 25 that is located near the third plate-shapedpart 30. The blockingportion 53 covers at least themiddle portion 25a of thesub-flow path 25 from a side of thesub-flow path 25 that is located near the third plate-shapedpart 30. The blockingportion 53 forms a portion of the tube path defining thesub-flow path 25. -
Fig. 10 conceptually illustrates how refrigerant flows within therefrigerant distributor 150 forming theheat exchanger 100 according toEmbodiment 2. When the refrigeration cycle apparatus 200 is in heating operation, refrigerant flows into therefrigerant distributor 150 in a two-phase gas-liquid state. The two-phase gas-liquid refrigerant flows into thebody 151 through therefrigerant inflow tube 60. Then, as represented by the arrow UF inFig. 10 , the refrigerant travels vertically upward in themain flow path 15a, which is defined in the first plate-shapedpart 10, from the oneend 151a toward theother end 151b. As the refrigerant travels vertically upward, a portion of the refrigerant passes through the second distribution holes 46 of the fourth plate-shapedpart 40, the distribution holes 26 of the second plate-shapedpart 20, and the third distribution holes 51 of the fifth plate-shapedpart 50 in this order before being distributed to theheat transfer tubes 70 by way of the insertion holes 31 defined in the third plate-shapedpart 30. - Refrigerant that accumulates in an upper portion of the
main flow path 15a flows into theinlet portion 25b of the second plate-shapedpart 20 via the communication holes 45 that communicate with the upper end 15a1 of themain flow path 15a. At this time, as represented by the arrow OF, the refrigerant flows outward in the third direction from themain flow path 15a serving as the first flow path toward thesub-flow path 25 serving as the second flow path. Then, as represented by the arrow DF, the refrigerant entering through theinlet portion 25b of thesub-flow path 25 flows downward in the direction of gravity in themiddle portion 25a of thesub-flow path 25 defined in the second plate-shapedpart 20. - Upon reaching the lower end of the
middle portion 25a of thesub-flow path 25, the refrigerant exits through theoutlet portion 25c into themain flow path 15a via the communication holes 45 that communicate with the lower end 15a2 of themain flow path 15a. At this time, as represented by the arrow IF, the refrigerant flows inward in the third direction from thesub-flow path 25 serving as the second flow path toward themain flow path 15a serving as the first flow path. After exiting through theoutlet portion 25c into themain flow path 15a, the exiting refrigerant, together with the refrigerant flowing into thebody 151 through therefrigerant inflow tube 60, travels vertically upward in themain flow path 15a, and is distributed to eachheat transfer tube 70. -
Fig. 11 illustrates the distribution of flow rate of refrigerant within therefrigerant distributor 150 forming theheat exchanger 100 according toEmbodiment 2. InFig. 11 , the horizontal axis represents refrigerant flow rate [kg/h], and the vertical axis represents the distance [m] from therefrigerant inlet 18 in the first direction in which theheat transfer tubes 70 are arranged. - As with
Embodiment 1, if thebody 151 is provided with thesub-flow path 25 serving as the second flow path, liquid refrigerant that accumulates in an upper portion of themain flow path 15a returns to a lower portion of themain flow path 15a by way of thesub-flow path 25. Thus, as represented by the arrow MU between the dotted line A and the solid line B, the flow rate of refrigerant decreases in the upper portion of themain flow path 15a as the refrigerant returns to the lower portion of themain flow path 15a. Further, as represented by the arrow MD between the dotted line A and the solid line B, the flow rate of refrigerant increases in the lower portion of themain flow path 15a as the refrigerant returns to the lower portion from the upper portion of themain flow path 15a. Consequently, as represented by the solid line B, the flow rate at which refrigerant flows in themain flow path 15a if thesub-flow path 25 is present is closer to the flow rate represented by the alternate long and short dash line C, than is the flow rate at which refrigerant flows in themain flow path 15a if nosub-flow path 25 is present. Therefore, therefrigerant distributor 150 with thesub-flow path 25 allows refrigerant to be evenly distributed to eachheat transfer tube 70, in comparison to a refrigerant distributor without thesub-flow path 25. - The
refrigerant distributor 150 includes the fourth plate-shapedpart 40, and the fifth plate-shapedpart 50. The fourth plate-shapedpart 40 has the communication holes 45, which are located between themain flow path 15a serving as the first flow path and each end of thesub-flow path 25, and the second distribution holes 46, which are located between themain flow path 15a serving as the first flow path and the distribution holes 26. The fifth plate-shapedpart 50 has the third distribution holes 51 located between the distribution holes 26 and the insertion holes 31. - In the
body 151 of therefrigerant distributor 150, the above-mentioned through-holes are provided in the fourth plate-shapedpart 40 and the fifth plate-shapedpart 50. This ensures that the flow of refrigerant between themain flow path 15a and thesub-flow path 25, and the flow of refrigerant from themain flow path 15a to theheat transfer tubes 70 are not hindered. Further, in thebody 151 of therefrigerant distributor 150, the tube path of thesub-flow path 25 can be defined by the blockingportion 44 of the fourth plate-shapedpart 40 and by the blockingportion 53 of the fifth plate-shapedpart 50. That is, for thebody 151 of therefrigerant distributor 150, theflat plate portion 11 of the first plate-shapedpart 10, and theflat plate portion 34 of the third plate-shapedpart 30 are not required for defining the tube path of thesub-flow path 25. - Consequently, the
sub-flow path 25 can be provided in the second plate-shapedpart 20 such that, when viewed in the direction of stacking of the plate-shaped parts, thesub-flow path 25 overlaps themain flow path 15a of the first plate-shapedpart 10, and the insertion holes 31 of the third plate-shapedpart 30. In other words, in thebody 151 of therefrigerant distributor 150, thesub-flow path 25 provided in the second plate-shapedpart 20 can be increased in width in the third direction (Y-axis direction). This leads to increased volume of thesub-flow path 25. As a result, in therefrigerant distributor 150 of theheat exchanger 100, the pressure loss in thesub-flow path 25 decreases and, consequently, when the circulation flow rate is high, a large amount of refrigerant that accumulates in the upper portion is allowed to circulate. This helps to prevent or reduce refrigerant maldistribution, and consequently improve the performance of theheat exchanger 100. -
Fig. 12 is an exploded perspective view of theheat exchanger 100 according to Embodiment 3, conceptually illustrating the configuration of major components of theheat exchanger 100.Fig. 13 is a cross-sectional view of theheat exchanger 100 according to Embodiment 3, conceptually illustrating where the first and second flow paths of therefrigerant distributor 150 forming theheat exchanger 100 communicate with each other.Fig. 14 conceptually illustrates how refrigerant flows within therefrigerant distributor 150 forming theheat exchanger 100 according to Embodiment 3. Components identical in function and operation to the components described above with reference toEmbodiment 1 are designated by the same reference signs and not described in further detail below. Theheat exchanger 100 according to Embodiment 3 differs from theheat exchanger 100 according toEmbodiment 1 in that, unlike for theoutlet portion 25c of theheat exchanger 100 according toEmbodiment 1, for an outlet portion 25c1 of theheat exchanger 100 according to Embodiment 3, the angle of the tube axis of the outlet portion 25c1 is specified. - As illustrated in
Fig. 12 , thesub-flow path 25 has themiddle portion 25a, theinlet portion 25b, and the outlet portion 25c1. Themiddle portion 25a defines a flow path extending in the first direction (Z-axis direction). The outlet portion 25c1 is located at the other end 25a2 of themiddle portion 25a in the first direction (Z-axis direction). - A tube axis TA of the outlet portion 25c1 is inclined toward a diagonal line DL of the second plate-shaped
part 20 relative to the first direction (Z-axis direction) and the third direction (Y-axis direction). Therefore, as represented by the arrow IF and the arrow UF inFig. 14 , the outlet portion 25c1 is inclined relative to the first direction and the third direction such that the direction of flow of refrigerant exiting the outlet portion 25c1 has a vector component of the direction of flow of refrigerant exiting therefrigerant inflow tube 60. That is, refrigerant exiting the outlet portion 25c1 is directed along the flow of refrigerant flowing in themain flow path 15a. - In the plate plane of the second plate-shaped
part 20, an outlet angle θ, which is an angle between the direction of the tube axis TA of the outlet portion 25c1 and the direction of gravity GD, is greater than or equal to 90 degrees. -
Fig. 15 illustrates the distribution of flow rate of refrigerant within therefrigerant distributor 150 forming theheat exchanger 100 according to Embodiment 3. InFig. 12 , the horizontal axis represents refrigerant flow rate [kg/h], and the vertical axis represents the distance [m] from therefrigerant inlet 18 in the first direction in which theheat transfer tubes 70 are arranged. - As with
Embodiment 1, if thebody 151 is provided with thesub-flow path 25 serving as the second flow path, liquid refrigerant that accumulates in an upper portion of themain flow path 15a returns to a lower portion of themain flow path 15a by way of thesub-flow path 25. Thus, as represented by the arrow MU between the dotted line A and the solid line B, the flow rate of refrigerant decreases in the upper portion of themain flow path 15a as the refrigerant returns to the lower portion of themain flow path 15a. Further, as represented by the arrow MD between the dotted line A and the solid line B, the flow rate of refrigerant increases in the lower portion of themain flow path 15a as the refrigerant returns to the lower portion from the upper portion of themain flow path 15a. Consequently, as represented by the solid line B, the flow rate at which refrigerant flows in themain flow path 15a if thesub-flow path 25 is present is closer to the flow rate represented by the alternate long and short dash line C, than is the flow rate at which refrigerant flows in themain flow path 15a if nosub-flow path 25 is present. Therefore, therefrigerant distributor 150 with thesub-flow path 25 allows refrigerant to be evenly distributed to eachheat transfer tube 70, in comparison to a refrigerant distributor without thesub-flow path 25. - As represented by the arrow IF and the arrow UF in
Fig. 14 , the outlet portion 25c1 is inclined relative to the first direction and the third direction such that the direction of flow of refrigerant exiting the outlet portion 25c1 has a vector component of the direction of flow of refrigerant exiting therefrigerant inflow tube 60. Consequently, the outlet portion 25c1 of thesub-flow path 25 provided in the second plate-shapedpart 20 is directed upward in the vertical direction, and the flow vector of refrigerant when the flow of refrigerant joins themain flow path 15a from thesub-flow path 25 is thus directed upward. This results in increased upward inertial force of refrigerant. Therefrigerant distributor 150 of theheat exchanger 100 therefore facilitates circulation of refrigerant in themain flow path 15a and thesub-flow path 25. Therefrigerant distributor 150 of theheat exchanger 100 allows for circulation of a large amount of refrigerant that accumulates in an upper portion of themain flow path 15a. This helps to prevent or reduce maldistribution of refrigerant. -
Fig. 16 is an exploded perspective view of theheat exchanger 100 according to Embodiment 4, conceptually illustrating the configuration of major components of theheat exchanger 100.Fig. 17 is a cross-sectional view of theheat exchanger 100 according to Embodiment 4, conceptually illustrating where the first and second flow paths of therefrigerant distributor 150 forming theheat exchanger 100 communicate with each other.Fig. 18 conceptually illustrates how refrigerant flows within therefrigerant distributor 150 forming theheat exchanger 100 according to Embodiment 4. Components identical in function and operation to the components described above with reference toEmbodiment 1 are designated by the same reference signs and not described in further detail below. Theheat exchanger 100 according to Embodiment 4 differs from theheat exchanger 100 according toEmbodiment 1 in that Embodiment 4 further specifies the configuration of themain flow path 15a serving as the first flow path. - As described above, the first
flow path portion 15 has themain flow path 15a defined inside the firstflow path portion 15. In theheat exchanger 100 according to Embodiment 4, themain flow path 15a serving as the first flow path decreases in cross-sectional area from the lower end 15a2, which is one end communicating with therefrigerant inflow tube 60, toward the upper end 15a1, which is the other end. With the first direction (Z-axis direction) defined as the up-down direction, themain flow path 15a decreases in cross-sectional area toward its upper portion. As illustrated inFig. 17 , the firstflow path portion 15 has a rectangular cross-section. However, the cross-section of the firstflow path portion 15 may not necessarily be rectangular but may be, for example, semicircular, semielliptical, or semioval. - The first
flow path portion 15 extends in the longitudinal direction of the first plate-shapedpart 10 from the oneend 151a of the main body portion toward theother end 151b. The firstflow path portion 15 is closed at both ends in the direction of extension of the firstflow path portion 15. InFig. 16 , the firstflow path portion 15 has aside wall 15b having the shape of a trapezoid when viewed in the direction of stacking of the first plate-shapedpart 10, the second plate-shapedpart 20, and the third plate-shapedpart 30. The firstflow path portion 15 has the shape of a quadrangular prism with theside wall 15b. The firstflow path portion 15 is tapered in the longitudinal direction of the first plate-shapedpart 10 from the lower end 15a2 near therefrigerant inlet 18 toward the upper end 15a1. The firstflow path portion 15 may not necessarily have the shape of a quadrangular prism with theside wall 15b but may have another shape, such as a circular truncated cone or a polygonal truncated cone. - The
main flow path 15a serving as the first flow path decreases in cross-sectional area from the lower end 15a2, which is one end communicating with therefrigerant inflow tube 60, toward the upper end 15a1, which is the other end. In the first direction (Z-axis direction), themain flow path 15a decreases in cross-sectional area toward the vertically upper portion of themain flow path 15a. This leads to increased flow rate of refrigerant through themain flow path 15a in therefrigerant distributor 150 of theheat exchanger 100. This helps to ensure that even if an operating condition of the air-conditioning apparatus causes the circulation rate of refrigerant to decrease, therefrigerant distributor 150 of theheat exchanger 100 allows refrigerant to reach the uppermost part of themain flow path 15a to thereby prevent or reduce maldistribution of refrigerant. -
Fig. 19 is an exploded perspective view of theheat exchanger 100 according to Embodiment 5, conceptually illustrating the configuration of major components of theheat exchanger 100.Fig. 20 is a conceptual side view of the interior of therefrigerant distributor 150 illustrated inFig. 19 .Fig. 21 is a cross-sectional view of theheat exchanger 100 according to Embodiment 5, conceptually illustrating where the first and second flow paths of therefrigerant distributor 150 forming theheat exchanger 100 communicate with each other. Components identical in function and operation to the components described above with reference toEmbodiment 1 are designated by the same reference signs and not described in further detail below. InEmbodiments 1 to 4, therefrigerant distributor 150 is a stack of multiple parts such as the first to fifth plate-shapedparts 10 to 50. By contrast, thebody 151 of therefrigerant distributor 150 according to Embodiment 5 is a tubular part. - The
body 151 of therefrigerant distributor 150 extends in the first direction (Z-axis direction), and connects with one end of each of theheat transfer tubes 70 to distribute refrigerant to theheat transfer tubes 70. - The
body 151 of therefrigerant distributor 150 has atubular portion 90 extending in the first direction (Z-axis direction) in which theheat transfer tubes 70 are arranged. Thebody 151 of therefrigerant distributor 150 has awall 91 in ahollow portion 95 of thetubular portion 90. Thewall 91 divides themain flow path 15a and thesub-flow path 25 from each other in the third direction, and has aninlet portion 92a and anoutlet portion 92b, which are through-holes and located at opposite ends of thewall 91 in the first direction. Further, thebody 151 of therefrigerant distributor 150 includes alid 94 for closing both ends of thetubular portion 90. - The
tubular portion 90 is in the form of a hollow circular cylinder extending in the direction of arrangement of theheat transfer tubes 70. However, thetubular portion 90 may not necessarily be in the form of a circular cylinder but may be in any tubular form. For example, thetubular portion 90 may be in the form of a cuboid box. InFig. 19 , thetubular portion 90 has a firsttubular portion 90a that connects with therefrigerant inflow tube 60, and a secondtubular portion 90b that connects with theheat transfer tubes 70. The firsttubular portion 90a and the secondtubular portion 90b each have the shape of a semicircular arc when viewed in cross-section perpendicular to the first direction (Z-axis direction). The firsttubular portion 90a and the secondtubular portion 90b of thetubular portion 90 may not be separate components. Alternatively, the firsttubular portion 90a and the secondtubular portion 90b may be integral with each other. - The
wall 91 is in the form of a strip elongated in one direction. Thewall 91 is a plate-shaped portion extending in the direction of arrangement of theheat transfer tubes 70. The longitudinal direction of thewall 91 aligns with the first direction (Z-axis direction) in which theheat transfer tubes 70 are arranged. The lateral direction of thewall 91 aligns with the second direction (X-axis direction) in which the tube paths of theheat transfer tubes 70 extend. The direction of plate thickness of thewall 91 aligns with the long-axis direction of eachheat transfer tube 70. Thewall 91 defines a plate plane extending in the first direction (Z-axis direction) and the second direction (X-axis direction). - The
wall 91 has theoutlet portion 92b at oneend 91b, which is an end connected with therefrigerant inflow tube 60. Thewall 91 has theinlet portion 92a at theother end 91a. Theinlet portion 92a and theoutlet portion 92b are through-holes extending through thewall 91 in the direction of plate thickness of thewall 91. In thebody 151, theinlet portion 92a and theoutlet portion 92b each define a flow path that extends in the third direction. - The
wall 91 has multiple insertion holes 93 each configured to receive one end of the corresponding one of theheat transfer tubes 70 inserted into theinsertion hole 93. Each of the insertion holes 93 is a through-hole extending through thewall 91 in the direction of plate thickness of thewall 91. Each of the insertion holes 93 is a cutout extending from anedge 91e, which extends in the first direction (Z-axis direction), toward anedge 91d opposite to theedge 91e. - The insertion holes 93 are arranged in parallel in the up-down direction along the length of the
wall 91. The insertion holes 93 are provided independently of each other in one-to-one correspondence to theheat transfer tubes 70. Eachinsertion hole 93 defines an opening with a flattened shape that conforms to the outer circumferential shape of the correspondingheat transfer tube 70. The entire circumference of the opening edge of eachinsertion hole 93 is joined by brazing to the outer circumferential surface of the correspondingheat transfer tube 70. By joining theheat transfer tubes 70 to thewall 91, theheat transfer tubes 70 are connected to thewall 91 such that theheat transfer tubes 70 communicate with themain flow path 15a serving as the first flow path, and thesub-flow path 25 serving as the second flow path. - The
lid 94 closes both ends of thetubular portion 90 in the direction in which thetubular portion 90 extends. Thelid 94 may be any part for closing both ends of thetubular portion 90 in the direction in which thetubular portion 90 extends. Thelid 94 may be a plate-shaped part, or may be a part that overlies both ends of thetubular portion 90. - The
hollow portion 95 inside thetubular portion 90 is defined by thetubular portion 90, and thelid 94 that closes both ends of thetubular portion 90. As illustrated inFig. 21 , thehollow portion 95 inside thetubular portion 90 is divided by thewall 91 into two spaces, a first space S1 and a second space S2. The first space S1 and the second space S2 communicate with each other via theinlet portion 92a and theoutlet portion 92b. - In the
body 151 of therefrigerant distributor 150, the first space S1 defines themain flow path 15a. Themain flow path 15a is a flow path through which refrigerant flows from the oneend 151a of thebody 151, which is an end connected with therefrigerant inflow tube 60, to theother end 151b. With the first direction (Z-axis direction) defined as the up-down direction, refrigerant flows upward in themain flow path 15a. Themain flow path 15a serving as the first flow path is formed so as to extend in the first direction (Z-axis direction), communicates with theheat transfer tubes 70, and is connected, at the lower end 15a2 in the first direction, with therefrigerant inflow tube 60 configured to cause refrigerant to flow into therefrigerant distributor 150. - In the
body 151 of therefrigerant distributor 150, the second space S2, theinlet portion 92a, and theoutlet portion 92b define thesub-flow path 25. Thesub-flow path 25 is a flow path through which refrigerant flows from theother end 151b to the oneend 151a of thebody 151, which is an end connected with therefrigerant inflow tube 60. With the first direction (Z-axis direction) defined as the up-down direction, refrigerant flows downward in thesub-flow path 25. Thesub-flow path 25 serving as the second flow path extends in the first direction, with theinlet portion 92a and theoutlet portion 92b at opposite ends being connected with themain flow path 15a serving as the first flow path. Thesub-flow path 25 serving as the second flow path is located in the third direction relative to themain flow path 15a serving as the first flow path. That is, themain flow path 15a and thesub-flow path 25 are located upstream and downstream in the direction of airflow created by theoutdoor fan 108 or theindoor fan 109 illustrated inFig. 1 . - The
body 151 of therefrigerant distributor 150 includes, in its inside, themain flow path 15a serving as the first flow path, and thesub-flow path 25 serving as the second flow path, which are flow paths through which refrigerant flows. In thebody 151 of therefrigerant distributor 150, themain flow path 15a and thesub-flow path 25 define a flow path in which refrigerant circulates. -
Fig. 22 is a cross-sectional view of the heat exchanger according to Embodiment 5, conceptually illustrating where the first and second flow paths of a modification of the refrigerant distributor forming the heat exchanger communicate with each other. Thetubular portion 90 may not necessarily be in the form of a circular cylinder illustrated inFig. 21 . Thetubular portion 90 may be in any tubular form. For example, thetubular portion 90 may be in the form of a semicircular cylinder illustrated inFig. 22 . -
Fig. 23 conceptually illustrates how refrigerant flows within therefrigerant distributor 150 forming theheat exchanger 100 according to Embodiment 5. As withEmbodiment 1, refrigerant that accumulates in an upper portion of themain flow path 15a flows into theinlet portion 92a defined in the second plate-shapedpart 20 and communicating with the upper end 15a1 of themain flow path 15a. At this time, as represented by the arrow OF, the refrigerant flows in the third direction from themain flow path 15a serving as the first flow path toward thesub-flow path 25 serving as the second flow path. Then, as represented by the arrow DF, the refrigerant entering through theinlet portion 92a of thesub-flow path 25 flows downward in the direction of gravity in thesub-flow path 25 defined in the second plate-shapedpart 20. - Upon reaching the lower end of the
sub-flow path 25, the refrigerant exits thesub-flow path 25 into themain flow path 15a through theoutlet portion 92b communicating with the lower end 15a2 of themain flow path 15a. At this time, as represented by the arrow IF, the refrigerant flows in the third direction from thesub-flow path 25 serving as the second flow path toward themain flow path 15a serving as the first flow path. After exiting through theoutlet portion 92b into themain flow path 15a, the exiting refrigerant, together with the refrigerant flowing into thebody 151 through therefrigerant inflow tube 60, travels vertically upward in themain flow path 15a, and is distributed to eachheat transfer tube 70. - The
refrigerant distributor 150 includes thetubular portion 90, thelid 94, and thewall 91. Thewall 91 divides themain flow path 15a serving as the first flow path, and thesub-flow path 25 serving as the second flow path from each other in the third direction. Thewall 91 has theinlet portion 92a and theoutlet portion 92b, which are through-holes and located at opposite ends of thewall 91 in the first direction. Theheat transfer tubes 70 are connected to thewall 91 so as to communicate with themain flow path 15a serving as the first flow path and thesub-flow path 25 serving as the second flow path. As a result, even if thebody 151 is a tubular part such as a circular tube, the above-mentioned configuration of theheat exchanger 100 helps to prevent or reduce an increase in the size of therefrigerant distributor 150 in the second direction in which refrigerant is circulated, and allows theheat exchanger 100 to be enlarged, within a range of structural constraints, in the second direction in which the tube paths of theheat transfer tubes 70 extend. Therefore, theheat exchanger 100 allows for increased heat transfer surface area of theheat transfer tubes 70, and also allows therefrigerant distributor 150 to be made compact without an increase in the size of therefrigerant distributor 150 in the direction in which the tube paths of theheat transfer tubes 70 extend. - The refrigeration cycle apparatus 200 includes the
heat exchanger 100 according to any one ofEmbodiments 1 to 5. Accordingly, the refrigeration cycle apparatus 200 provides an effect similar to any one ofEmbodiments 1 to 5. -
Embodiments 1 to 5 mentioned above can be practiced in combination with each other. The configurations described above with reference to the embodiments are intended to be illustrative only. These configurations can be combined with other known techniques, or can be partially omitted or changed without departing from the scope of the present disclosure. For example, therefrigerant distributor 150 or other components according toEmbodiments 1 to 5 may be of a longitudinally mounted type with thebody 151 extending in the vertical direction, or may be of a transversely mounted type with thebody 151 extending in the horizontal direction. Therefrigerant distributor 150 or other components according toEmbodiment 1 to 5 may be designed such that thebody 151 is inclined relative to the vertical direction. Reference Signs List - 10: first plate-shaped part, 11: flat plate portion, 11a: flat plate portion, 11b: flat plate portion, 15: first flow path portion, 15a: main flow path, 15a1: upper end, 15a2: lower end, 15b: side wall, 18: refrigerant inlet, 20: second plate-shaped part, 24: blocking portion, 25: sub-flow path, 25a: middle portion, 25a1: end, 25a2: end, 25b: inlet portion, 25c: outlet portion, 25c1: outlet portion, 26: distribution hole, 30: third plate-shaped part, 31: insertion hole, 34: flat plate portion, 40: fourth plate-shaped part, 44: blocking portion, 45: communication hole, 46: second distribution hole, 50: fifth plate-shaped part, 51: third distribution hole, 53: blocking portion, 60: refrigerant inflow tube, 70: heat transfer tube, 70a: first side end, 70b: second side end, 70c: flat surface, 70d: flat surface, 71: gap, 72: refrigerant passage, 75: heat transfer fin, 90: tubular portion, 90a: first tubular portion, 90b: second tubular portion, 91: wall, 91a: end, 91b: end, 91d: edge, 91e: edge, 92a: inlet portion, 92b: outlet portion, 93: insertion hole, 94: lid, 95: hollow portion, 100: heat exchanger, 101: compressor, 102: flow switching device, 103: indoor heat exchanger, 104: pressure reducing device, 105: outdoor heat exchanger, 106: outdoor unit, 107: indoor unit, 108: outdoor fan, 109: indoor fan, 110: refrigerant circuit, 111: extension pipe, 112: extension pipe, 115: flow path portion, 150: refrigerant distributor, 151: body, 151a: end, 151b: end, 200: refrigeration cycle apparatus.
Claims (10)
- A heat exchanger comprising:a plurality of heat transfer tubes arranged at intervals in a first direction, and configured to circulate refrigerant in a second direction intersecting the first direction; anda refrigerant distributor extending in the first direction and is connected to one end of each of the plurality of heat transfer tubes, the refrigerant distributor being configured to distribute the refrigerant to the plurality of heat transfer tubes,whereinthe refrigerant distributor includes, in its inside, a first flow path and a second flow path through which the refrigerant flows,the first flow path is formed so as to extend in the first direction, communicates with the plurality of heat transfer tubes, and is connected with an inflow tube configured to cause the refrigerant to flow into the refrigerant distributor, andthe second flow path is formed so as to extend in the first direction, with opposite ends thereof being connected with the first flow path, and is formed so as to be positioned in a third direction relative to the first flow path, when a direction intersecting a plane parallel to the first direction and to the second direction is defined as the third direction.
- The heat exchanger of claim 1,whereinthe refrigerant distributor includesa first plate-shaped part including the first flow path,a second plate-shaped part including a distribution hole and the second flow path, the distribution hole being a through-hole located between the plurality of heat transfer tubes and the first flow path, anda third plate-shaped part including an insertion hole, the insertion hole being a through-hole into which each of the plurality of heat transfer tubes is inserted,the first plate-shaped part, the second plate-shaped part, and the third plate-shaped part are stacked together, andin a direction of stacking of the first plate-shaped part, the second plate-shaped part, and the third plate-shaped part, the first flow path and the opposite ends overlap each other, and the first flow path, the distribution hole, and the insertion hole overlap each other.
- The heat exchanger of claim 2,
wherein a plurality of the distribution holes are provided in the first direction. - The heat exchanger of claim 2 or 3,
wherein the second flow path is disposed beside both sides of the distribution hole in the third direction. - The heat exchanger of any one of claims 2 to 4,whereinthe refrigerant distributor includesa fourth plate-shaped part disposed between the first plate-shaped part and the second plate-shaped part, anda fifth plate-shaped part disposed between the second plate-shaped part and the third plate-shaped part,the fourth plate-shaped part includesa communication hole, the communication hole being a through-hole located between the first flow path and the opposite ends, anda second distribution hole, the second distribution hole being a through-hole located between the first flow path and the distribution hole, andthe fifth plate-shaped part includes a third distribution hole, the third distribution hole being a through-hole located between the distribution hole and the insertion hole.
- The heat exchanger of any one of claims 2 to 5,whereinthe opposite ends includean inlet portion into which the refrigerant flows from the first flow path, andan outlet portion from which the refrigerant flows out into the first flow path, andthe inlet portion and the outlet portion are formed so as to extend in the third direction.
- The heat exchanger of any one of claims 2 to 5,whereinthe opposite ends includean inlet portion into which the refrigerant flows from the first flow path,an outlet portion from which the refrigerant flows out into the first flow path, andthe outlet portion is inclined relative to the first direction and the third direction such that a direction of flow of the refrigerant exiting the outlet portion has a vector component of a direction of flow of the refrigerant exiting the refrigerant inflow tube.
- The heat exchanger of any one of claims 1 to 7,
wherein the first flow path decreases in cross-sectional area from one end toward an other end, the one end being an end connected with the inflow tube. - The heat exchanger of claim 1,whereinthe refrigerant distributor includesa tubular portion extending in the first direction,a lid that closes both ends of the tubular portion, anda wall that, in a hollow portion of the tubular portion, divides the first flow path and the second flow path from each other in the third direction, and has an inlet portion and an outlet portion, the inlet portion and the outlet portion being through-holes located at opposite ends of the wall in the first direction, andthe plurality of heat transfer tubes are connected to the wall so as to communicate with the first flow path and the second flow path.
- A refrigeration cycle apparatus comprising the heat exchanger of any one of claims 1 to 9.
Applications Claiming Priority (1)
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PCT/JP2020/002321 WO2021149223A1 (en) | 2020-01-23 | 2020-01-23 | Heat exchanger and refrigeration cycle apparatus |
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EP4095476A1 true EP4095476A1 (en) | 2022-11-30 |
EP4095476A4 EP4095476A4 (en) | 2023-01-11 |
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EP (1) | EP4095476B1 (en) |
JP (1) | JP7278430B2 (en) |
ES (1) | ES2975262T3 (en) |
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US10563895B2 (en) * | 2016-12-07 | 2020-02-18 | Johnson Controls Technology Company | Adjustable inlet header for heat exchanger of an HVAC system |
CN114216166B (en) * | 2021-11-25 | 2023-04-07 | 青岛海信日立空调***有限公司 | Air conditioner |
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JP2015068622A (en) | 2013-09-30 | 2015-04-13 | ダイキン工業株式会社 | Heat exchanger and air conditioner |
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JPH05346297A (en) * | 1992-06-15 | 1993-12-27 | Nippon Light Metal Co Ltd | Heat exchanger |
JP3007839B2 (en) * | 1996-03-13 | 2000-02-07 | 松下冷機株式会社 | Shunt |
JP4536243B2 (en) * | 2000-10-31 | 2010-09-01 | 株式会社ティラド | Heat exchanger for air conditioning |
WO2005124259A1 (en) * | 2004-06-15 | 2005-12-29 | Showa Denko K.K. | Heat exchanger |
JP4281634B2 (en) * | 2004-06-28 | 2009-06-17 | 株式会社デンソー | Refrigerant evaporator |
EP2108909A1 (en) * | 2008-04-07 | 2009-10-14 | Delphi Technologies, Inc. | Heat exchanger provided with a fitting block |
EP2372283B1 (en) * | 2010-03-23 | 2013-09-04 | Delphi Technologies, Inc. | Heat exchanger with a manifold plate |
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CN105229404B (en) * | 2013-05-15 | 2018-07-17 | 三菱电机株式会社 | Laminated type header box, heat exchanger and conditioner |
WO2014184915A1 (en) * | 2013-05-15 | 2014-11-20 | 三菱電機株式会社 | Laminated header, heat exchanger, and air conditioner |
JP2017044428A (en) * | 2015-08-27 | 2017-03-02 | 株式会社東芝 | Heat exchanger, split flow component and heat exchanging device |
JP2018100800A (en) * | 2016-12-20 | 2018-06-28 | 三菱重工サーマルシステムズ株式会社 | Heat exchanger and air conditioner |
JP6840262B2 (en) * | 2017-10-13 | 2021-03-10 | 三菱電機株式会社 | Laminated headers, heat exchangers, and refrigeration cycle equipment |
JPWO2019087235A1 (en) * | 2017-10-30 | 2020-10-22 | 三菱電機株式会社 | Refrigerant distributor and refrigeration cycle equipment |
JP7108177B2 (en) * | 2018-03-30 | 2022-07-28 | ダイキン工業株式会社 | heat exchangers and air conditioners |
CN115111939A (en) * | 2018-10-29 | 2022-09-27 | 三菱电机株式会社 | Heat exchanger, outdoor unit, and refrigeration cycle device |
-
2020
- 2020-01-23 JP JP2021572221A patent/JP7278430B2/en active Active
- 2020-01-23 ES ES20915558T patent/ES2975262T3/en active Active
- 2020-01-23 WO PCT/JP2020/002321 patent/WO2021149223A1/en unknown
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EP4095476A4 (en) | 2023-01-11 |
TWI768340B (en) | 2022-06-21 |
ES2975262T3 (en) | 2024-07-04 |
TW202129218A (en) | 2021-08-01 |
JPWO2021149223A1 (en) | 2021-07-29 |
JP7278430B2 (en) | 2023-05-19 |
WO2021149223A1 (en) | 2021-07-29 |
EP4095476B1 (en) | 2024-02-14 |
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