Heat exchanger and air conditioning device using the same

Abstract

The heat exchanger includes a header and a plurality of flat tubes, the plurality of flat tubes extending in a first direction and arranged at intervals from each other in a second direction, the header extending in the second direction and connecting the ends of the adjacent flat tubes in the first direction to each other, wherein a flow path formed inside the header is formed with a partition, an insertion portion, a first communication path, and a second communication path, the partitions being arranged between the adjacent flat tubes and closing at least a portion of the flow path between the flat tubes, the insertion portion being formed by being sandwiched between the adjacent partitions and into which the flat tubes are inserted, the first communication path connecting one side of the adjacent insertion portions to each other, the second communication path connecting the other side of the adjacent insertion portions to each other, the cross-sectional area of ​​the first communication path perpendicular to the second direction being larger than the cross-sectional area of ​​the second communication path perpendicular to the second direction, and a first refrigerant inlet for allowing refrigerant to flow into the header and connected to the flow path being formed in the first communication path. Thus, the refrigerant pressure loss is reduced, and the refrigerant distribution is made uniform, thereby improving the performance of the heat exchanger.

Description

Technical Field

[0001] The present disclosure relates to a heat exchanger and an air conditioning apparatus using the same. Background Art

[0002] It is known that a heat exchanger is installed in an indoor unit in an air conditioning device and functions as a condenser. The liquid refrigerant condensed by the heat exchanger is depressurized by an expansion valve and becomes a gas-liquid two-phase state in which a gas refrigerant and a liquid refrigerant are mixed. Then, in a heat exchanger installed in an outdoor unit and functions as an evaporator, the liquid refrigerant in the gas-liquid two-phase state evaporates and becomes a low-pressure gas refrigerant. Thereafter, the low-pressure gas refrigerant sent from the heat exchanger flows into a compressor installed in the outdoor unit, is compressed and becomes a high-temperature and high-pressure gas refrigerant, and is discharged from the compressor again. This cycle is then repeated.

[0003] In addition, among such heat exchangers, there is known a heat exchanger using a heat transfer tube with a flat cross section in order to improve energy efficiency by reducing ventilation resistance and save refrigerant by reducing the volume inside the tube. However, when the header is miniaturized in order to save refrigerant, the flow resistance inside the header increases and the performance of the heat exchanger decreases, so it is difficult to achieve both performance improvement and refrigerant saving.

[0004] In order to achieve both improved performance and refrigerant saving, a heat exchanger is proposed that includes two main header chambers extending in the parallel direction of the heat transfer tubes and a plurality of sub-header chambers that branch from the main header chambers in the horizontal direction and are arranged in the parallel direction of the heat transfer tubes (see, for example, Patent Document 1). In this case, a header is provided that allows the refrigerant to flow into the main header chamber to flow into the refrigerant tubes connected to the plurality of sub-header chambers, respectively, thereby achieving uniform refrigerant distribution.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Publication No. 2007-183076 Summary of the invention

[0008] Problems to be solved by the invention

[0009] However, the heat exchanger of Patent Document 1 has the following problem: when the flow path of the header is reduced in diameter to reduce the amount of refrigerant, the increase in flow resistance leads to an increase in refrigerant pressure loss and uneven distribution of the refrigerant in the gas-liquid two-phase state, which degrades the heat exchanger performance.

[0010] The present disclosure is intended to solve the above-mentioned problems, and an object of the present disclosure is to provide a heat exchanger capable of improving heat exchanger performance by reducing refrigerant pressure loss and achieving uniform refrigerant distribution, and an air conditioning apparatus using the heat exchanger.

[0011] Solutions to Solve Problems

[0012] The heat exchanger disclosed in the present invention comprises a header and a plurality of flat tubes, wherein the plurality of flat tubes are arranged to extend along a first direction, and the cross section of the plurality of flat tubes in a second direction perpendicular to the first direction is flat, and the plurality of flat tubes are arranged to be spaced apart from each other along the second direction, and the header is arranged to extend along the second direction, and the ends of the adjacent flat tubes in the first direction are connected to each other, wherein the header has a flow path for circulating the refrigerant formed therein, and a partition, an insertion portion, a first connecting path, and a second connecting path are formed in the flow path, and the partitions are respectively arranged between the adjacent flat tubes to close at least a portion of the flow path between the flat tubes, thereby inhibiting the refrigerant from flowing along the flow path. The refrigerant flows in the second direction, the insertion portion is formed by being sandwiched by adjacent partitions, and is a space for the refrigerant to flow along a third direction intersecting the first direction and the second direction of each of the flat tubes, and each of the flat tubes is inserted respectively, the first connecting passage connects one side of each of the adjacent insertion portions in the third direction with each other, and the second connecting passage connects the other side of each of the adjacent insertion portions in the third direction with each other, the cross-sectional area of ​​the first connecting passage perpendicular to the second direction is larger than the cross-sectional area of ​​the second connecting passage perpendicular to the second direction, and the first refrigerant inlet for the refrigerant to flow into the header and connected to the flow path is formed in the first connecting passage.

[0013] Furthermore, an air conditioning device using the heat exchanger of the present disclosure includes a heat pump type refrigerant circuit having at least a compressor, a condenser, an expansion valve, and an evaporator, and the heat exchanger is mounted as the condenser or the evaporator.

[0014] Effects of the Invention

[0015] According to the present disclosure, a partition, an insertion portion, a first connecting passage, and a second connecting passage are formed in the flow passage of the header. The partitions are respectively arranged between adjacent flat tubes to close at least a portion of the flow passage between the flat tubes. The insertion portion is formed by being sandwiched between adjacent partitions and is a space for refrigerant to flow, into which the flat tubes are respectively inserted. The first connecting passage connects one side of the adjacent insertion portions to each other, and the second connecting passage connects the other side of the adjacent insertion portions to each other. The cross-sectional area of ​​the first connecting passage is larger than that of the second connecting passage, and the first refrigerant inlet that allows the refrigerant to flow into the header and is connected to the flow passage is formed in the first connecting passage. Therefore, the refrigerant pressure loss caused by the expansion and contraction of the refrigerant flow occurring in the insertion portion is reduced, and the increase in pressure loss caused by the reduction in the flow passage diameter can be suppressed.

[0016] In addition, when the header is divided by a center plane passing through the center of the third direction intersecting the first direction and the second direction of the flat tube, a first refrigerant inlet connected to the flow path is provided in at least one of the two regions, and the flow path cross-sectional area of ​​the first connecting path provided with the first refrigerant inlet is larger than the flow path cross-sectional area of ​​the second connecting path. In other words, the structure is provided with the following two connecting paths: a connecting path that mainly utilizes inertial force to transport refrigerant from the refrigerant inlet to the insertion portion of the flat tube due to a relatively large flow path cross-sectional area; and a connecting path that mainly utilizes diffusion to exchange gas and liquid through the insertion portion of the flat tube due to a relatively small flow path cross-sectional area. Thus, by alleviating uneven distribution caused by changes in the refrigerant flow rate, the performance of the heat exchanger is improved, and the energy efficiency of an air conditioner equipped with a heat exchanger can be improved. In this way, the refrigerant pressure loss is reduced, and the refrigerant distribution is made uniform, thereby improving the performance of the heat exchanger. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a refrigerant circuit diagram showing an example of the air-conditioning apparatus according to Embodiment 1.

[0018] Figure 2 This is a perspective view showing an example of a heat exchanger mounted in the air-conditioning apparatus according to Embodiment 1.

[0019] Figure 3 It is expressed in cross section Figure 2 A perspective view of a portion of a header of a heat exchanger.

[0020] Figure 4 Yes means Figure 2 Schematic diagram of a horizontal cross section of a header.

[0021] Figure 5 Yes means Figure 4 Schematic diagram of the cross section of the header viewed along the AA line.

[0022] Figure 6 Yes means Figure 4 Schematic diagram of the cross section of the header viewed along arrow BB.

[0023] Figure 7 Yes means Figure 4 Schematic diagram of the cross section of the header viewed from the CC direction.

[0024] Figure 8 The diagram is a perspective view schematically showing a cross section of a header for explaining the flow of a refrigerant in the heat exchanger of the comparative example.

[0025] Fig. 9 The flow of the refrigerant in the header of the first embodiment is illustrated by a cross section. Figure 1 A perspective view of a portion of a header in a heat exchanger.

[0026] Fig.10 This is a conceptual diagram showing the pressure loss reduction effect of the header according to the first embodiment.

[0027] Fig.11 It is a schematic diagram showing the distribution of holes among the headers in the flat tubes of the heat exchanger of the comparative example.

[0028] Fig.12 This is a schematic diagram showing the distribution of holes in the header at the flat tubes according to the first embodiment.

[0029] Fig.13 This is a diagram for explaining the flow of refrigerant in the header according to Embodiment 1.

[0030] Fig.14 This is a graph conceptually showing the performance improvement effect and the refrigerant amount reduction effect of the heat exchanger according to the first embodiment.

[0031] Fig.15 This is a graph showing the performance loss improvement rate obtained by the refrigerant distribution with respect to the flow path cross-sectional area of ​​the heat exchanger according to Embodiment 1.

[0032] Fig.16 It is a schematic cross-sectional view showing a modified example of the header of the first embodiment.

[0033] Fig.17 This is an exploded perspective view showing an example of the header according to the first embodiment.

[0034] Fig.18 This is an exploded perspective view showing a modification of the header of the first embodiment.

[0035] Fig.19 This is an exploded perspective view showing a modification of the header of the first embodiment.

[0036] Fig. 20This is an exploded perspective view showing a modification of the header of the first embodiment.

[0037] Fig.21 This is a cross-sectional perspective view showing a modified example of the header of the first embodiment.

[0038] Fig. 22 The perspective view for explaining the refrigerant flow in the modified example of the header of Embodiment 1 is a perspective view showing a part of the header in cross section.

[0039] Fig.23 It is a schematic diagram showing a horizontal cross section of a header in the heat exchanger according to the second embodiment.

[0040] Fig.24 It is a schematic diagram for explaining the distribution performance of the header in the heat exchanger of the comparative example.

[0041] Fig.25 This is a schematic diagram for explaining the distribution performance of the header in the heat exchanger according to the second embodiment.

[0042] Fig.26 A modified example of the heat exchanger according to the second embodiment is shown, and is a schematic diagram showing a cross section of a header on the XZ plane.

[0043] Fig. 27 This is a perspective view showing a part of the header of the heat exchanger according to the third embodiment in cross section.

[0044] Fig.28 express Fig. 27 The header is a schematic diagram showing a horizontal cross-section of the header.

[0045] Fig.29 Yes means Fig.28 Schematic diagram of the cross section of the header viewed from the DD direction.

[0046] Fig.30 Yes means Fig.29 A schematic cross-sectional view of a modified example of a header.

[0047] Fig.31 It is a schematic diagram showing a horizontal cross section of a header in the heat exchanger according to the fourth embodiment.

[0048] Fig.32 It is a schematic diagram showing a horizontal cross section of a header in the heat exchanger according to the fifth embodiment.

[0049] Fig.33 It is a schematic diagram showing a horizontal cross section of a header in a heat exchanger according to Embodiment 6.

[0050] Fig.34 It is a schematic diagram showing a horizontal cross section of a header, showing a modification of the heat exchanger according to the sixth embodiment.

[0051] Fig.35 It is a schematic diagram showing a horizontal cross section of a header, showing a modification of the heat exchanger according to the sixth embodiment.

[0052] Fig.36 It is a schematic diagram showing a horizontal cross section of a header, showing a modification of the heat exchanger according to the sixth embodiment.

[0053] Fig.37 It is a schematic diagram showing a horizontal cross section of a header, showing a modification of the heat exchanger according to the sixth embodiment. DETAILED DESCRIPTION

[0054] The following is an explanation of the implementation mode based on the accompanying drawings. In addition, in each figure, the components marked with the same figure mark are the same or corresponding components, which is common throughout the entire text of the specification. In addition, the forms of the constituent elements shown in the entire specification are only examples after all, and are not limited to these descriptions. In addition, in the following figures, the relationship between the sizes of the constituent components is sometimes different from the actual situation.

[0055] Implementation Method 1

[0056] Structure of the air conditioning device 200

[0057] First, the air conditioning apparatus according to Embodiment 1 will be described. Figure 1 is a refrigerant circuit diagram showing an example of the air-conditioning apparatus 200 according to Embodiment 1. Figure 1 In FIG. 1 , the flow of the refrigerant during the cooling operation is indicated by the dotted arrows, and the flow of the refrigerant during the heating operation is indicated by the solid arrows.

[0058] like Figure 1 As shown, the air conditioning device 200 includes an outdoor unit 201 and an indoor unit 202. The outdoor unit 201 includes a heat exchanger 10 as an outdoor heat exchanger, an outdoor fan 13, a compressor 14, and a four-way valve 15. The indoor unit 202 includes an indoor heat exchanger 16, a throttling device 17, and an indoor fan not shown. The compressor 14, the four-way valve 15, the heat exchanger 10, the throttling device 17, and the indoor heat exchanger 16 are connected by a refrigerant pipe 12 to form a refrigerant circuit.

[0059] The compressor 14 compresses the refrigerant. The refrigerant compressed by the compressor 14 is discharged and sent to the four-way valve 15. The compressor 14 can be constituted by, for example, a rotary compressor, a scroll compressor, a screw compressor, or a reciprocating compressor.

[0060] The heat exchanger 10 functions as a condenser during heating operation and functions as an evaporator during cooling operation. In the case of the present embodiment 1, the heat exchanger 10 is configured as a fin-tube type heat exchanger, and the fins 1 and the flat tubes 2 as flat heat-conducting tubes are extended along a first direction Y as the extension direction of the flat tubes 2, and are alternately arranged along a second direction Z orthogonal to the first direction Y, thereby forming the fin-tube type heat exchanger, which will be described later in detail. The cross section of the flat tube 2 perpendicular to the first direction Y is configured as a flat shape, and the flat tube 2 has a plurality of refrigerant flow paths 20 for the refrigerant to flow therein. In addition, a header 11 (see FIG. 1 ) is provided at the end of the flat tube 2 in the first direction Y. Figure 2 ).

[0061] The throttling device 17 expands and decompresses the refrigerant that has passed through the heat exchanger 10 or the indoor heat exchanger 16. The throttling device 17 can be composed of, for example, an electric expansion valve that can adjust the flow rate of the refrigerant. In addition, as the throttling device 17, not only the electric expansion valve can be applied, but also a mechanical expansion valve or a capillary tube using a diaphragm in the pressure receiving part can be applied.

[0062] The indoor heat exchanger 16 functions as an evaporator during heating operation and as a condenser during cooling operation. The indoor heat exchanger 16 can be composed of, for example, a fin-tube heat exchanger, a microchannel heat exchanger, a shell-and-tube heat exchanger, a heat pipe heat exchanger, a double-pipe heat exchanger, or a plate heat exchanger.

[0063] The four-way valve 15 switches the flow of the refrigerant in the heating operation and the cooling operation. That is, the four-way valve 15 switches the flow of the refrigerant in the heating operation by connecting the discharge port of the compressor 14 to the heat exchanger 10 and connecting the suction port of the compressor 14 to the indoor heat exchanger 16. In addition, the four-way valve 15 switches the flow of the refrigerant in the cooling operation by connecting the discharge port of the compressor 14 to the indoor heat exchanger 16 and connecting the suction port of the compressor 14 to the heat exchanger 10.

[0064] The outdoor fan 13 is attached to the heat exchanger 10 and supplies air as a heat exchange fluid to the heat exchanger 10 .

[0065] An indoor fan (not shown) is attached to the indoor heat exchanger 16 and supplies air as a heat exchange fluid to the indoor heat exchanger 16 .

[0066] Operation of the air conditioning device 200

[0067] Next, the flow of the refrigerant and the operation of the air conditioner 200 will be described together. First, the cooling operation performed by the air conditioner 200 will be described. Figure 1The solid arrows in the figure indicate the flow of the refrigerant during the cooling operation. Here, the operation of the air conditioning device 200 will be described by taking the case where the heat exchange fluid is air and the heat exchanged fluid is the refrigerant as an example.

[0068] like Figure 1 As shown, by driving the compressor 14, a high-temperature and high-pressure gaseous refrigerant is discharged from the compressor 14. Thereafter, the refrigerant flows in accordance with the dotted arrows. The high-temperature and high-pressure gaseous refrigerant (single-phase) discharged from the compressor 14 flows into the heat exchanger 10 functioning as a condenser via the four-way valve 15. In the heat exchanger 10, heat exchange is performed between the high-temperature and high-pressure gaseous refrigerant flowing in and the air supplied by the outdoor fan 13, and the high-temperature and high-pressure gaseous refrigerant is condensed to become a high-pressure liquid refrigerant (single-phase).

[0069] The high-pressure liquid refrigerant sent out from the heat exchanger 10 is converted into a two-phase refrigerant of low-pressure gas refrigerant and liquid refrigerant by the throttling device 17. The two-phase refrigerant flows into the indoor heat exchanger 16 that functions as an evaporator. In the indoor heat exchanger 16, heat exchange is performed between the two-phase refrigerant flowing in and the air supplied by the indoor fan (not shown), and the liquid refrigerant in the two-phase refrigerant evaporates and becomes a low-pressure gas refrigerant (single phase). The indoor room is cooled by this heat exchange. The low-pressure gas refrigerant sent out from the indoor heat exchanger 16 flows into the compressor 14 via the four-way valve 15, is compressed to become a high-temperature and high-pressure gas refrigerant, and is discharged from the compressor 14 again. This cycle is then repeated.

[0070] Next, the heating operation performed by the air-conditioning device 200 will be described. Figure 1 The dotted arrows in FIG. 1 indicate the flow of the refrigerant during the heating operation.

[0071] like Figure 1 As shown, by driving the compressor 14, a high-temperature and high-pressure gaseous refrigerant is discharged from the compressor 14. Thereafter, the refrigerant flows as indicated by the dotted arrows.

[0072] The high-temperature and high-pressure gas refrigerant (single-phase) discharged from the compressor 14 flows into the indoor heat exchanger 16 functioning as a condenser via the four-way valve 15. In the indoor heat exchanger 16, heat exchange is performed between the high-temperature and high-pressure gas refrigerant flowing in and the air supplied by the indoor fan (not shown), and the high-temperature and high-pressure gas refrigerant is condensed to become a high-pressure liquid refrigerant (single-phase). The indoor room is heated by this heat exchange.

[0073] The high-pressure liquid refrigerant sent from the indoor heat exchanger 16 is converted into a two-phase refrigerant of low-pressure gas refrigerant and liquid refrigerant by the throttling device 17. The two-phase refrigerant flows into the heat exchanger 10 that functions as an evaporator. In the heat exchanger 10, heat exchange is performed between the two-phase refrigerant that flows in and the air supplied by the outdoor fan 13, and the liquid refrigerant in the two-phase refrigerant evaporates to become a low-pressure gas refrigerant (single phase).

[0074] The low-pressure gas refrigerant sent from the heat exchanger 10 flows into the compressor 14 through the four-way valve 15, is compressed to become a high-temperature and high-pressure gas refrigerant, and is again discharged from the compressor 14. This cycle is then repeated.

[0075] When the refrigerant flows into the compressor 14 in a liquid state during the cooling operation and the heating operation, liquid compression occurs, which may cause a failure of the compressor 14. Therefore, it is desirable that the refrigerant flowing out of the indoor heat exchanger 16 during the cooling operation or the heat exchanger 10 during the heating operation is a gas refrigerant (single phase).

[0076] Here, in the evaporator, when heat is exchanged between the air supplied from the fan and the refrigerant flowing inside the heat transfer tube constituting the evaporator, moisture in the air condenses, and water droplets are generated on the surface of the evaporator. The water droplets generated on the surface of the evaporator drip downward along the fins and the surface of the heat transfer tube, and are discharged as drain water at the bottom of the evaporator.

[0077] In addition, during heating operation at a low outside temperature, heat exchanger 10 functions as an evaporator, so moisture in the air may frost heat exchanger 10. Therefore, in air conditioning device 200, when the outside air temperature becomes below a certain temperature (for example, 0°C), a "defrosting operation" for removing frost is performed.

[0078] "Defrost operation" is an operation in which hot gas (high-temperature and high-pressure gas refrigerant) is supplied from the compressor 14 to the heat exchanger 10 in order to prevent frost from adhering to the heat exchanger 10 functioning as an evaporator. In addition, the defrost operation may be performed when the duration of the heating operation reaches a specified value (for example, 30 minutes). In addition, the defrost operation may be performed before the heating operation is performed when the heat exchanger 10 is below a certain temperature (for example, minus 6°C). The frost and ice adhering to the heat exchanger 10 are melted by the hot gas supplied to the heat exchanger 10 during the defrost operation.

[0079] For example, in order to supply hot gas directly from the compressor 14 to the heat exchanger 10 during the defrosting operation, a bypass refrigerant pipe (not shown) may be used to connect the discharge port of the compressor 14 and the heat exchanger 10. In addition, in order to supply hot gas from the compressor 14 to the heat exchanger 10, a structure may be provided in which the discharge port of the compressor 14 is connected to the heat exchanger 10 via a refrigerant flow switching device (e.g., a four-way valve 15).

[0080] About Heat Exchanger 10

[0081] Next, the heat exchanger 10 mounted in the air-conditioning apparatus 200 in Embodiment 1 will be described. Figure 2 This is a perspective view showing an example of the heat exchanger 10 mounted in the air-conditioning apparatus 200 according to Embodiment 1. Figure 3 It is expressed in cross section Figure 2 FIG. 1 is a perspective view of a portion of a header 11 of a heat exchanger 10 . Figure 4 Yes means Figure 2 Schematic diagram of a horizontal cross section of the header 11. Figure 5 Yes means Figure 4 Schematic diagram of a cross section of the header 11 viewed along the arrow AA. Figure 6 Yes means Figure 4 Schematic diagram of a cross section of the header 11 viewed along the arrow BB. Figure 7 Yes means Figure 4 Schematic diagram of a cross section of the header 11 viewed along the CC line.

[0082] In addition, Figure 2 AF indicated by arrows indicates the direction from the outdoor fan 13 (refer to Figure 1 ) represents the ventilation direction of air supplied to the heat exchanger 10, and the arrow RF represents the flow direction of the refrigerant supplied to the heat exchanger 10. The flat tubes 2 are arranged at intervals from each other in such a manner that the flat flat surfaces are parallel to the ventilation direction AF and the flat surfaces are opposite to each other. That is, the flat tubes 2 are arranged at intervals from each other along the second direction Z, which is the short side direction of the flat shape, on the cross section perpendicular to the first direction Y. In addition, in the flat shape of the cross section of each flat tube 2, the length in the long side direction is sometimes referred to as the width, the length in the short side direction is referred to as the thickness, the long side direction is referred to as the width direction, and the short side direction is referred to as the thickness direction. The direction intersecting the first direction Y and the second direction Z of each flat tube 2, that is, the long side direction (width direction) of the cross section of each flat tube 2, is a direction parallel to the flat surface, and is referred to as the third direction X below. In addition, in each figure, the first direction Y, the second direction Z, and the third direction X are shown as being orthogonal to each other, but the three directions may also intersect at an angle close to 90 degrees, such as 80 degrees.

[0083] A typical heat exchanger 10 has a plurality of flat tubes 2 connected to a header 11 , the length of which in the first direction Y is longer than the length in the third direction X, and the length in the second direction Z is also longer than the length in the third direction X. Therefore, the header 11 is elongated along the first direction Y.

[0084] like Figure 2 As shown, the heat exchanger 10 of the first embodiment is, for example, a fin-tube heat exchanger of a single-row structure, and fins 1 and flat tubes 2 are alternately stacked along the second direction Z, which is the width direction of the heat exchanger 10. In addition, the fins 1 may be, for example, a plate type connected to a plurality of flat tubes 2, or may be a corrugated type fin sandwiched between the flat surfaces of two flat tubes 2. In the heat exchanger 10, the flat tubes 2 are arranged in a horizontal direction, which is a first direction Y, with a gap between each other in the vertical direction, and the fins 1 are sandwiched between each adjacent flat tube 2. In addition, the headers 11 that communicate the ends are connected to the ends of each adjacent flat tube 2 in the first direction Y, which is the direction of extension. In addition, the headers 11 having the structure of the first embodiment described below may be provided only at one end of each flat tube 2 in the first direction Y, or may be provided at both ends. In addition, the case where the flat tubes 2 are arranged in a horizontal direction, which is the second direction Z, in the vertical direction is described here, but the second direction Z is not limited to this. For example, the flat tubes 2 may be extended in the horizontal direction toward the second direction Z, and arranged side by side with a space between them in the vertical direction as the first direction Y.

[0085] like Figure 3 As shown, the header 11 has a flow path 21 formed inside for the refrigerant to flow. In the flow path 21, partitions 7 are respectively arranged between adjacent flat tubes 2. The partitions 7 close at least a portion of the flow path 21 between the adjacent flat tubes 2. In addition, in the flow path 21, an insertion portion 23 for inserting the flat tube 2 is provided as a space formed by being sandwiched between adjacent partitions 7 according to the number of flat tubes 2.

[0086] Here, as in Figure 4 as well as Figure 5 As shown by the dashed line in the figure, a center plane 100 is assumed, and the center plane 100 passes through the center of the third direction X intersecting the first direction Y and the second direction Z of the plurality of flat tubes 2. In addition, the center plane 100 is a plane parallel to the first direction Y and the second direction Z. Figure 4 as well as Figure 5Indicated by a single-dot chain line. Furthermore, when the header 11 is divided into two regions 41 and 42 with the center plane 100 as a boundary, communication paths 22a and 22b are formed in each region to connect adjacent insertion portions 23. The communication paths 22a and 22b are formed in the two regions 41 and 42 to be connected along the second direction Z in which the flat tubes 2 are arranged in parallel, that is, the extension direction of the header 11. The communication path 22a is connected to the refrigerant inlet 3 without passing through the insertion portion 23, and the communication path 22b is connected to the refrigerant inlet 3 through the insertion portion 23, and the flow path cross-sectional area of ​​the communication path 22a is larger than the flow path cross-sectional area of ​​the communication path 22b located in the other region 42.

[0087] exist Figure 4 as well as Figure 5 In the figure, as a typical example, the structure in which the communication paths 22a and 22b are provided on both sides of the flat tubes 2 in the third direction X in the flow path 21 of the header 11 is shown, but it is sufficient to have at least one communication path in each of the two regions 41 and 42, and it is not necessary to provide them on both sides in the third direction X. A plurality of communication paths 22a and 22b may be provided in either or both of the two regions 41 and 42.

[0088] The flat tube 2 is a porous tube structure having a plurality of adjacent refrigerant flow paths 20 formed therein, and the communication paths 22a and 22b are as follows. Figure 6 as well as Figure 7 As shown, the insertion portion 23 is connected to each refrigerant flow path 20 inside the flat tube 2. In addition, at least one of the two regions 41 and 42 of the header 11 is provided with a refrigerant inlet 3 as a first refrigerant inlet connected to the flow path 21 (see Figure 2 ).

[0089] Next, the flow of the refrigerant in the header 11 will be described in comparison with a comparative example. Figure 8 This is a perspective view schematically showing a cross section of a header 501 for explaining the flow of the refrigerant in the heat exchanger of the comparative example. Fig. 9 The flow of the refrigerant in the header 11 of the first embodiment is illustrated by a cross section. Figure 1 FIG. 1 is a perspective view of a portion of a header 11 in a heat exchanger 10 . Fig.10 This is a conceptual diagram showing the pressure loss reduction effect of the header 11 according to the first embodiment. Fig.11 Schematic diagram showing the distribution of holes in the header 501 of the heat exchanger of the comparative example in the flat tube 502 . Fig.12 This is a schematic diagram showing the distribution among the holes of the header 11 in the flat tubes 2 according to the first embodiment. Fig.13 This is a diagram for explaining the flow of refrigerant in the header 11 according to Embodiment 1. Fig.14This is a graph conceptually showing the performance improvement effect and the refrigerant amount reduction effect of the heat exchanger 10 according to Embodiment 1. Fig.15 This is a graph showing the performance loss improvement rate obtained by the refrigerant distribution with respect to the flow path cross-sectional area of ​​the heat exchanger according to Embodiment 1.

[0090] Here, in the header, in order to ensure the connection strength between the flat tubes 2 and the header 11 and prevent the quality degradation caused by the brazing material used for connection flowing into the refrigerant flow path 20 in the flat tubes 2, the flat tubes 2 are usually structured to protrude into the flow path 21 inside the header 11.

[0091] like Figure 8 As shown, in the header 501 of the comparative example, a contraction portion CA and an expansion portion BA of the flow path 521 are formed around the insertion portion 523 of each flat tube 502 at the flow path 521. Therefore, in the header 501 of the comparative example, the refrigerant flows in the flow path 521 while repeatedly contracting and expanding, and thus a refrigerant pressure loss occurs due to the expansion and contraction of the flow that is positively correlated with the mass velocity of the refrigerant. In particular, the number of flat tubes 502 connected to the upstream side of the header 501 is set to n, and the average flow velocity flowing in the flat tubes 502 is set to Gm [kg / m 2 s], the flow velocity flowing in the insertion portion 523 of the n flat tubes 502 becomes n×Gm [kg / m 2 s]. Furthermore, the refrigerant flows n times through the expansion portion BA and the contraction portion CA of the flow path 521 from the flat tube 502 connected to the upstream side of the header 501 to the flat tube 502 connected to the downstream side, so the refrigerant pressure loss increases and the heat exchanger performance decreases.

[0092] In contrast, in the heat exchanger 10 of the first embodiment, the flow path 21 in the header 11 is provided with the partition 7, and the flow paths 21 in the two regions 41 and 42 of the header 11 are provided with the connecting paths 22a and 22b for connecting the insertion portions 23 of the flat tubes 2 to each other. Fig. 9 As shown, the refrigerant flows through these communication paths 22a and 22b. The communication paths 22a and 22b are provided on both sides of the center plane 100 in the third direction X, and the insertion portion 23 functions as a flow path for the refrigerant to flow in the third direction X by using the partition 7. The refrigerant flows in the third direction X along the length direction of the end of the flat tube 2 in the insertion portion 23. Fig. 9As shown in FIG. 1 , a typical insertion portion 23 is formed into a flat shape whose length in the second direction Z is smaller than its width in the third direction X. In addition, the insertion portion 23 is set to have a fixed distance from the end of the flat tube 2, and the connecting passages 22a and 22b are set to have a fixed flow passage cross-sectional area in the second direction Z. The refrigerant flowing in the connecting passages 22a and 22b is distributed to the insertion portion 23 in sequence and then flows into each flat tube 2. Due to such a structure, it is not easily affected by Figure 8 The structure of the comparative example shown in the figure has the effect of expansion and contraction due to the insertion of the end portion of the flat tube 2.

[0093] In addition, in the communication passage 22b, the flow passage cross-sectional area is smaller than that of the communication passage 22a, so that the flow rate of the refrigerant from the upstream side to the downstream side relative to the communication passage 22a is reduced on the basis of reducing the amount of refrigerant, so that the gas-liquid ratio of the refrigerant between different insertion parts 23 is equalized and the gas-liquid exchange is performed. Therefore, the excessive supply of liquid refrigerant to the downstream due to inertial force is reduced, and it is possible to achieve both the reduction of the amount of refrigerant and the performance of the heat exchanger.

[0094] In the header 11 of the present embodiment 1, the refrigerant flow rate can be reduced to about 1 / n compared to the header 501 in which the refrigerant repeatedly flows through the reduction portion CA and the expansion portion BA formed around the insertion portion 523 of the flow path 521 of the comparative example. In addition, since the number of times the refrigerant flows through the insertion portion 23 before reaching each flat tube 2 is suppressed to about 1 to 2 times, the pressure loss caused by the expansion and contraction of the flow can be reduced. Therefore, in the heat exchanger 10 of the present embodiment 1 having such a header 11, the increase in pressure loss caused by the reduction in the diameter of the flow path 21 can be suppressed, and the reduction in the amount of refrigerant and the improvement in the performance of the heat exchanger can be achieved at the same time.

[0095] exist Fig.10 In FIG. 1 , the dotted line represents the refrigerant distribution efficiency in the header 501 of the comparative example, and the solid line represents the refrigerant distribution efficiency in the header 11 of the first embodiment. Fig.10As shown, in particular, when the ratio of the pressure loss caused by the expansion and contraction of the above-mentioned flow in the pressure loss in the flow path 21 of the header 11 is attempted to be taken into account, the ratio is greater in low-power (Japanese: low capacity) operation where the mass velocity of the refrigerant is low than in high-power (Japanese: high capacity) operation where the mass velocity of the refrigerant is high. Here, the dotted circle H indicates that the effect of reducing the pressure loss of the refrigerant in the header 501 and the header 11 is greater as the mass velocity is lower. This has been clearly shown in the inventor's experiments, and the performance improvement effect is particularly large in the low-power operation that dominates the cycle efficiency of air conditioners, etc. In addition, compared with olefin-based refrigerants, propane or DME (dimethyl ether) and other R32 refrigerants or R410A refrigerants, the refrigerant flow rate per unit power of refrigerants with low gas density is higher, so the performance improvement effect obtained by reducing the pressure loss is greater. In addition, as olefin-based refrigerants, HFO1234yf or HFO1234ze (E) are cited.

[0096] Next, use Fig.11 and Fig.12 The distribution of the refrigerant in the refrigerant flow path 520 of the flat tube 502 at the header 501 of the comparative example and the refrigerant flow path 20 of the flat tube 2 at the header 11 of the first embodiment is described. In addition, in order to ensure the pressure resistance, the flat tube 502 and the flat tube 2 are generally formed in the same manner as a multi-hole tube structure in which a plurality of refrigerant flow paths 520 and 20 are formed by providing a partition portion inside.

[0097] like Fig.11 As shown, in the header 501 of the comparative example, the flow path 521 is provided only at one end portion in the third direction X, which is the longitudinal direction of the end portion of each flat tube 502, and the flow path 521 is provided with a connecting path 522 that connects the insertion portions 523 of each flat tube 502. The refrigerant flows into the insertion portion 523 from the end portion connected to the connecting path 522 on one side and is distributed to each refrigerant flow path 520 in sequence, so that the refrigerant is unevenly distributed among the refrigerant flow paths 520, and the thermal conductivity is reduced.

[0098] In contrast, in the header 11 of the first embodiment, Fig.12 As shown, flow paths 21 are provided at both ends of each flat tube 2 in the third direction X, and connecting paths 22a and 22b are provided in each of the flow paths 21. That is, in the header 11, connecting paths 22a and 22b of the insertion portion 23 of the flat tube 2 are provided in two different regions 41 and 42 that intersect the center plane 100 on the cross section of the flat tube 2, respectively, thereby reducing uneven distribution of the refrigerant between the flow paths 20 and improving the performance of the heat exchanger.

[0099] In addition, since at least one communication path 22a and 22b for connecting the insertion parts 23 to each other is provided in the flow paths 21 of each of the two different regions 41 and 42 having the center plane 100 of the flat tube 2 as a boundary, the flow of the refrigerant flows from the communication path 22a located in one region 41 into the insertion part 23. Then, the flow is branched into a main flow flowing toward the flat tube 2 in the insertion part 23 and a branch flow flowing toward the communication path 22b located in the other region 42. With regard to the flow of the refrigerant flowing in the communication path 22b located in the other region 42, since the flow path cross-sectional area of ​​the communication path 22b is smaller than that of the communication path 22a, the refrigerant flow velocity in the first direction is lower than that of the communication path 22a, and the refrigerant transport effect obtained by the inertial force is relatively small. As a result, the effect caused by the diffusion of the gas-liquid concentration gradient caused by the flow path 21 is increased.

[0100] At this time, if Fig.13 As shown in FIG. 1 , in order to alleviate the gas-liquid concentration gradient, diffusion occurs between the adjacent insertion portions 23 of the adjacent flat tubes 2, and exchange of gas refrigerant or liquid refrigerant occurs. Therefore, in the header 11 of the first embodiment, it is possible to alleviate the gas-liquid concentration gradient. Fig.12 In the header 501 of the comparative example, the inertial force of the flow that controls the gas-liquid two-phase ratio (hereinafter referred to as distribution) flowing in the flat tubes 502 leads to uneven distribution, thereby improving the performance of the heat exchanger. As a result, the energy efficiency of the air conditioner 200 equipped with the heat exchanger 10 can be improved.

[0101] exist Fig.14 In FIG. 1 , the dotted line indicates the heat exchanger performance of the heat exchanger 10 having the header 501 of the comparative example, and the solid line indicates the heat exchanger performance of the heat exchanger 10 having the header 11 of the first embodiment. Fig.14 As shown, in the heat exchanger 10 of the present embodiment 1, the heat exchanger performance is less sensitive to the tube internal volume than the heat exchanger having the comparative example header 501, and the heat exchanger performance can be maintained with a lower volume, thereby achieving both reduction in refrigerant amount and improvement in performance.

[0102] exist Fig.15In the figure, the horizontal axis is the area ratio of the flow path cross-sectional area Sb of the communication path 22a to the flow path cross-sectional area Sa of the communication path 22b, and the value 0 indicates that the manifold 501 does not have the communication path 22b, and the value 1 indicates that the flow path cross-sectional areas of the communication paths 22a and 22b are equal. In addition, the vertical axis indicates the improvement rate of the performance loss obtained by the refrigerant distribution, with the decrease rate of the heat exchanger performance of the heat exchanger 10 equipped with the manifold 501 of the comparative example relative to the heat exchanger performance of the heat exchanger 10 assuming equal distribution being set as 100%. The present inventors confirmed through this evaluation test that by making the flow path cross-sectional area ratio Sb / Sa smaller than 1, the distribution of the refrigerant is improved, and the heat exchanger performance loss is reduced by a maximum of 50% or more. When the flow path cross-sectional area ratio Sb / Sa is significantly reduced, the wetted edge length is relatively large compared to the flow path cross-sectional area of ​​the communication path 22b, and the surface tension of the liquid film on the wall hinders the distribution improvement effect obtained by diffusion, resulting in a decrease in performance. On the other hand, when the flow path cross-sectional area ratio Sb / Sa increases to 1 or more, the refrigerant flow rate flowing in the communication path 22b increases, the inertial force increases, and the distribution improvement effect obtained by diffusion is hindered, and the performance decreases. In particular, by making the flow path cross-sectional area ratio Sb / Sa larger than 0.15 and smaller than 0.8, the heat exchanger performance loss is reduced by a maximum of 30% or more, which is a great effect.

[0103] Effects of Implementation Method 1

[0104] As described above, in the heat exchanger 10 of the first embodiment and the air conditioner 200 equipped with the heat exchanger 10, the partition 7 that closes at least a portion of the flow path 21 between the adjacent flat tubes 2 is provided in the header 11. In addition, between the insertion portions 23 of the flat tubes 2 formed by being sandwiched between the adjacent partitions 7, the communication paths 22a and 22b that communicate between the insertion portions 23 are formed. At this time, the communication path 22a in the flow path 21 of the header 11 is configured not to pass through the insertion portion 23 into which the flat tube 2 is inserted, thereby reducing the refrigerant pressure loss caused by the expansion and contraction of the refrigerant flow occurring in the insertion portion 23, and suppressing the increase in pressure loss caused by the reduction in the diameter of the flow path 21.

[0105] In addition, when the header 11 is divided into two different areas 41 and 42 with the center plane 100 passing through the center of the flat tube 2 in the third direction X as a boundary, the two areas 41 and 42 are provided with communication paths 22a and 22b, respectively. The refrigerant inlet 3 connected to the flow path 21 is provided in at least one area 41 of the two areas 41 and 42. By providing the refrigerant inlet 3 in the communication path 22a, a structure is formed in which the communication path 22a and the communication path 22b are provided. The communication path 22a mainly uses inertial force to transport the refrigerant from the refrigerant inlet 3 to the insertion part 23 of the flat tube 2, and the communication path 22b mainly uses diffusion to exchange gas and liquid through the insertion part 23 of the flat tube 2. As a result, the uneven distribution caused by the change in the refrigerant flow rate is alleviated, the heat exchanger performance is improved, and the energy efficiency of the air conditioner 200 equipped with the heat exchanger 10 can be improved. In this way, the refrigerant pressure loss is reduced, and the refrigerant distribution is made uniform, so that the heat exchanger performance can be improved. In addition, at least at the junction between the insertion portion 23 and the connecting passage 22b, the width of the insertion portion 23 in the second direction is smaller than the width of the solid partition portion 7 in the second direction, thereby reducing the influence of the inertial force of the refrigerant flow in the connecting passage 22a on the flow of the connecting passage 22b, thereby improving the heat exchanger performance. In addition, the partition portion 7 is wide and solid, so it is possible to save refrigerant, which is particularly effective.

[0106] In addition, Figure 1 to Figure 3 In the description, the structure in which the headers 11 are respectively arranged above and below the heat exchanger 10 in the gravity direction is described, but the arrangement of the headers 11 is not limited to this. As the arrangement of the headers 11 relative to the heat exchanger 10, for example, they may be arranged only on one side of the upper and lower sides in the gravity direction. In addition, in a case where the flat tubes 2 are extended not in the first direction Y but in the second direction Z and arranged with intervals between them along the first direction Y, the headers 11 may be arranged on at least one side of the left and right side surfaces that are orthogonal to the gravity direction. However, it should be noted that arrangement on the upper or lower side in the gravity direction can alleviate the hindrance to diffusion caused by the gas-liquid density difference, and is therefore more effective. In addition, in Figure 1 In the air conditioner 200, the heat exchanger 10 is mounted in the outdoor unit 201, but it can also be mounted in the indoor unit 202 without affecting its effect. In addition, the upstream side or downstream side of the header 11 may have a region where the partition 7 is not provided.

[0107] Fig.16 1 is a cross-sectional schematic diagram showing a modified example of the header 11 of the first embodiment. Fig.16 As shown, a part of the adjacent flat tubes 2 may not be partitioned by the partitions 7. In particular, by reducing the number of partitions 7 in the communication passages 22 at the locations where diffusion occurs, it is possible to reduce the contribution of the inertial force to the distribution.

[0108] Here, a specific configuration example of the header 11 will be described. Fig.17 This is an exploded perspective view showing an example of the header 11 according to the first embodiment. Fig.18 It is an exploded perspective view showing a modified example of the header 11 according to the first embodiment. Fig.19 It is an exploded perspective view showing a modified example of the header 11 according to the first embodiment. Fig. 20 1 is an exploded perspective view showing a modified example of the header 11 of the first embodiment. Figures 17 to 20 2 shows an example of the component structure of the header 11.

[0109] like Fig.17 As shown, the header 11 of the first embodiment is preferably configured as follows: a plurality of flat tubes 2, tubular refrigerant inlet ports 3, and partitions 7 are assembled to the rectangular box-shaped header 11, and openings formed at both ends of the header 11 in the second direction Z are closed by a cover member 80. In this case, the components are preferably joined by, for example, brazing.

[0110] In addition, as in Fig.18 As shown in the modified example of the header 11 in , the header 11 may also be composed of rectangular box-shaped cover members 81 and 82 obtained by opening the mutually opposing surfaces. In this case, the cover members 81 and 82 form a flow path 21, and the flow path 21 is respectively provided with the above-mentioned connecting paths 22a and 22b (here, the illustration is omitted for convenience). In addition, a plurality of flat tubes 2 are assembled to the partition 7 in a state of being arranged along the second direction Z which is the thickness direction of these flat tubes 2, and the cover members 81 and 82 are assembled in a manner that covers both ends of the partition 7 assembled with these flat tubes 2 in the width direction, that is, the third direction X on the flat tube 2. With this structure, compared with the case where the flat tube 2 is inserted and assembled to the partition 7 toward the first direction Y, it is easier to adjust the position of the flat tube 2, and it is possible to suppress the occurrence of closure or flattening of the flow path 21 due to poor positioning.

[0111] In addition, if Fig.19 As shown in the modified example of the header 11 in the figure, the header 11 can also be formed by assembling a member 82 extruded in the second direction Z and a cover member 80 closing both ends of the member 82 in the second direction Z. In this case, the above-mentioned connecting passages 22a and 22b are formed in the space surrounded by the extruded member and the partition member. In addition, the refrigerant inlet 3 is assembled at one end of the closing connecting passage 22a in the cover member 80 covering both ends of the extruded member 82 in the second direction Z. With this structure, in addition to Fig.18 In addition to the effects of the modified example shown, the flow path cross-sectional areas of the communication paths 22a and 22b can be easily adjusted.

[0112] In addition, if Fig. 20 As shown in the modified example of the header 11 in FIG. 1 , the header 11 may be formed by stacking a plurality of plate-like members 91 to 94. In this case, the plate-like member 91 is formed with a penetration portion 90 through which a plurality of flat tubes 2 are penetrated and the flat tubes 2 are held, and the plate-like member 91 functions as a cover. In addition, the plate-like member 92 is formed with an insertion portion 23 corresponding to the number of the flat tubes 2. In addition, the penetration portion 90 is formed in a size consistent with the outer periphery of the flat tube 2 and is formed smaller than the insertion portion 23, so that the upper surface side of the insertion portion 23 is closed in a state where the flat tube 2 is assembled. The plate-like member 93 is formed with communication paths 22a and 22b at both end sides in the third direction X. The plate-like member 94 is connected to the tubular refrigerant inlet 3 and constitutes the bottom surface of the header 11. And, these plate-like members 91 to 94 are stacked and assembled along the first direction Y of the flat tube 2 to constitute the header 11.

[0113] Fig.21 1 is a cross-sectional perspective view showing a modified example of the header 11 of the first embodiment. Fig.21 As shown in FIG. 1 , the communication paths 22a and 22b of the header 11 of the first embodiment only need to be provided in the two regions 41 and 42 respectively with the center plane 100 of the flat tube 2 as the boundary, and the communication paths 22a and 22b may also be arranged below the insertion portion 23. With this structure, the header 11 can be arranged without being oriented in the ventilation direction AF of the heat exchanger 10 (the third direction X of the header 11, see FIG. 1 ). Figure 2 ) The flow path diameters of the communication paths 22a and 22b are designed on the premise of enlarging the size of the communication paths 22a and 22b. Therefore, different flat tubes 2 can be arranged in parallel along the third direction X of the flat tubes 2, and space saving can be achieved when different heat exchangers 10 are respectively configured on the upstream side and the downstream side of the ventilation direction AF of the heat exchanger 10 or when the heat exchanger 10 is disposed in a product housing.

[0114] Fig. 22 The following is a perspective view showing a portion of the header 11 in cross section for explaining the refrigerant flow in a modified example of the header 11 of the first embodiment. Fig. 22 As shown, the header 11 may be divided into a first heat transfer tube group 51 disposed on the upstream side of the flow path 21 and a second heat transfer tube group 52 disposed on the downstream side of the flow path 21, and heat transfer parts may be provided on the upstream side and the downstream side of the header 11. In this case, the pressure loss of the flow path 21 in the header 11 is reduced, thereby reducing the difference in condensation temperature (or evaporation temperature) of the refrigerant flowing in the heat transfer part on the upstream side and the heat transfer part on the downstream side, thereby having an advantage of increasing the effect of improving the performance of the heat exchanger.

[0115] Implementation Method 2

[0116] Next, the heat exchanger 10 according to Embodiment 2 and the air-conditioning apparatus 200 equipped with the heat exchanger 10 will be described. Fig.23 It is a schematic diagram showing a horizontal cross section of a header 11 in a heat exchanger 10 according to the second embodiment. Fig.24 It is a schematic diagram for explaining the distribution performance of the header 501 in the heat exchanger of the comparative example. Fig.25 This is a schematic diagram for explaining the distribution performance of the header 11 in the heat exchanger 10 according to the second embodiment. Fig.26 The modified example of the heat exchanger 10 of the second embodiment is shown in a schematic diagram showing a cross section of the header 11 on the XZ plane. Fig.25 In consideration of easy observation, reference numerals are omitted for the various parts of the header 11, but the header 11 and Fig.23 is the same, so it is equivalent to Fig.23 The header in.

[0117] Embodiment 2 changes a part of the header 11 of Embodiment 1, and the overall structure of the heat exchanger 10 and the air conditioner 200 is the same as that of Embodiment 1, so illustration and description are omitted, and the same or corresponding parts as those of Embodiment 1 are marked with the same reference numerals as those of Embodiment 1. The header 11 of the heat exchanger 10 of Embodiment 1 is basically a symmetrical structure with two regions sandwiching the center plane 100, but it can also be asymmetrical as in this Embodiment 2.

[0118] The header 11 of the heat exchanger 10 of the second embodiment is as follows: Fig.23 As shown, the refrigerant inlet 24 is arranged along the ventilation direction AF (refer to FIG. 1 ) of the heat exchanger 10 with the center plane 100 of the header 11 as the boundary. Figure 2 ) is eccentric to the third direction X of the flat tube 2 of the one region 41. Correspondingly, the position of the communication path 22a on the one region 41 side is eccentric in the third direction X from the position of the communication path 22b on the other region 42 side that is symmetrical with respect to the center plane 100. That is, the position where the refrigerant inlet 24 is connected to the communication path 22a on the one region 41 side deviates from the position of the communication path 22b on the other region 42 side that is symmetrical with respect to the center plane 100 in the third direction X. For example, in the case of the second embodiment, the refrigerant inlet 24 is provided at a position eccentric to the one region 41 side in two different regions along the third direction X of the header 11. In addition, the configuration of the refrigerant inlet 24 is not limited thereto, and may be configured eccentric to the other region 42 side.

[0119] like Fig.24As shown, in the structure of the comparative example, the flow path 521 having the communication path 522 is provided only at one end of the flat tube 502 in the third direction X. Therefore, the amount of liquid delivered to the flat tube 502 is governed by the inertial force, and the liquid refrigerant is delivered to the downstream flat tube 502 in operation with a large mass speed, and the liquid refrigerant is delivered to the upstream flat tube 502 in operation with a small mass speed, and the heat exchanger performance is degraded.

[0120] In contrast, in the header 11 of the heat exchanger 10 of the second embodiment, Fig.25 As shown, regarding the distribution characteristics from the communication passages 22a and 22b to the insertion portion 23, the inertial force of the refrigerant plays a dominant role in the communication passage 22a located in one area 41. In addition, in the communication passage 22b located in another area 42, the diffusion caused by the collision from the insertion portion 23 to the communication passage 22b plays a dominant role. At this time, in the operation with a large mass velocity, the inertial force of the flow in the communication passage 22a located in one area 41 is large, and the amount of liquid refrigerant transported to the insertion portion 23 of the downstream flat tube 2 is large, but the outflow amount to the communication passage 22b located in another area 42 is also large. On the other hand, in the operation with a small mass velocity, the inertial force of the flow in the communication passage 22a located in one area 41 is small, and the amount of liquid refrigerant transported to the insertion portion 23 of the downstream flat tube 2 is small, but the amount of liquid transported due to diffusion in the communication passage 22b located in another area 42 is large. As a result, the sensitivity of the refrigerant distribution to the mass velocity is reduced, and the performance is improved in a wide power range.

[0121] In addition, if Fig.23 As shown, when the refrigerant inlet 24 is formed eccentrically from the center plane 100 of the cross section of the flat tube 2 to one area 41, the flow path diameter of the connecting path 22a located in one area 41 is set to a hydraulic diameter (Japanese: hydraulic diameter) D1. In addition, the flow path diameter of the connecting path 22b located in another area 42 is set to a hydraulic diameter D2. At this time, by making the hydraulic diameter D1 of the connecting path 22a located in one area 41 larger than the hydraulic diameter D2 of the connecting path 22b located in another area 42, the liquid conveying effect obtained by diffusion in the connecting path 22b located in another area 42 is improved, thereby improving performance (refer to Fig.25 ). For example, as a method of reducing the hydraulic diameter D2, Fig.26 As shown, the porous body 6 may be disposed in the communication passage 22b of the flow passage 21 located in the other region 42 to increase the wetted edge area relative to the advancing path (liquid passage) of the refrigerant passing through the communication passage 22b.

[0122] Effects of Implementation 2

[0123] As described above, in the heat exchanger 10 of the second embodiment and the air conditioner 200 equipped with the heat exchanger 10, the refrigerant inlet 24 is eccentrically arranged along the third direction X (for example, the one region 41 side) of the flat tube 2, which is the ventilation direction AF of the heat exchanger 10, from the center plane 100 of the header 11. Regarding the distribution characteristics from the communication paths 22a and 22b to the insertion portion 23, the inertial force of the refrigerant plays a dominant role in the communication path 22a located in the one region 41, and the diffusion caused by the collision from the insertion portion 23 to the communication path 22b located in the other region 42 plays a dominant role. As a result, the sensitivity of the refrigerant distribution to the mass velocity is reduced, and the heat exchanger performance can be improved in a wide power range.

[0124] In addition, when the flow path diameter of the communication path 22a located in one area 41 is set to the hydraulic diameter D1, and the flow path diameter of the communication path 22b located in the other area 42 is set to the hydraulic diameter D2, the hydraulic diameter D1 is made larger than the hydraulic diameter D2. In this way, the liquid transport effect obtained by diffusion in the communication path 22b of the other area 42 is improved, and the heat exchanger performance can be improved.

[0125] Implementation 3

[0126] Next, a heat exchanger 10 according to Embodiment 3 and an air-conditioning apparatus 200 equipped with the heat exchanger 10 will be described. Fig. 27 This is a perspective view showing a part of a header 11 of a heat exchanger 10 according to the third embodiment in cross section. Fig.28 express Fig. 27 11 is a schematic diagram showing a horizontal cross section of the header 11. Fig.29 Yes means Fig.28 Schematic diagram of a cross section of the header 11 viewed along the arrow DD. Fig.30 Yes means Fig.29 A schematic cross-sectional view of a modified example of the header 11.

[0127] Embodiment 3 changes a portion of the header 11 of Embodiment 2. The structures of the heat exchanger 10 and the air conditioning device 200 are the same as those of Embodiment 1, so the description is omitted, and the same or corresponding parts as those of Embodiment 1 are marked with the same figure marks as those of Embodiment 1.

[0128] The header 11 of the third embodiment is as follows Figure 27 to Figure 29 As shown, at the center plane 100 (refer to Fig.26 ) along the ventilation direction AF of the heat exchanger 10 as the third direction X of the flat tubes 2 (refer to Figure 2) is provided at an eccentric position of the refrigerant inlet 24. Specifically, the refrigerant inlet 24 is provided, for example, on the side of one of the two regions 41 and 42. In addition, only in the connecting passage 22a of the flow path 21 connected to the refrigerant inlet 24, a contraction hole 4 is provided at a connection portion connecting the connecting passage 22a and the insertion portion 23 into which the flat tube 2 is inserted. In addition, the contraction hole 4 is provided as shown in FIG. Fig.29 As shown, it is preferred that the insertion portion 23 (see Fig. 27 as well as Fig.28 ) is arranged so as to be located on the same straight line as the flat tube 2.

[0129] Effects of Implementation 3

[0130] As described above, in the header 11 of the third embodiment, the contraction hole 4 is provided between the communication passage 22a of the one region 41 having the refrigerant inlet 24 and the insertion portion 23 of the flat tube 2, thereby reducing the sensitivity of the gas-liquid two-phase distribution to the inertial force. In addition, the contraction hole 4 is not provided in the communication passage 22b, so that the header is not enlarged. Therefore, the distribution improvement effect obtained by diffusion in the communication passage 22b of the other region 42 is enhanced, and the heat exchanger performance can be improved.

[0131] In addition, the contraction hole 4 is Fig.30 As shown, it is also possible to: relative to the insertion portion 23 (see Fig.25 as well as Fig.26 ) is arranged at a position eccentric in the first direction Y parallel to the flat tubes 2 from a position on the same straight line as the flat tubes 2.

[0132] In this way, the contraction hole 4 is eccentric with respect to the insertion portion 23 in the second direction Z, so the flow path center of the contraction hole 4 is usually offset from the central axis of the flat tube 2 located near the center of the insertion portion 23. As a result, the collision of the refrigerant flowing from the communication path 22a of one area 41 to the communication path 22b of another area 42 with the portion protruding toward the flow path 21 of the flat tube 2 is reduced, and the refrigerant flow rate to the communication path 22b of another area 42 is increased. As a result, the distribution improvement effect obtained by diffusion is improved by promoting agitation, thereby improving the performance of the heat exchanger.

[0133] Implementation 4

[0134] Next, the heat exchanger 10 according to Embodiment 4 and the air-conditioning apparatus 200 equipped with the heat exchanger 10 will be described. Fig.31It is a schematic diagram showing a horizontal cross section of the header 11 in the heat exchanger 10 of Embodiment 4. Embodiment 4 changes a part of the header 11 of Embodiment 2, and the structures of the heat exchanger 10 and the air conditioning device 200 are the same as those of Embodiment 1, so the description is omitted, and the same or corresponding parts as those of Embodiment 1 are marked with the same reference numerals as those of Embodiment 1.

[0135] The header 11 of the heat exchanger 10 of the fourth embodiment is as follows Fig.31 As shown, at least one of the partitions 7 disposed between adjacent flat tubes 2 is provided with a connecting flow path 5 that penetrates the partition 7 along the third direction X. The connecting flow path 5 connects the connecting flow path 22a and the connecting flow path 22b that are disposed in two regions 41 and 42 that are obtained by dividing the flow path 21 with the center plane 100 of the flat tube 2 as a boundary. The connecting flow path 5 is parallel to the insertion portion 23, that is, the ventilation direction AF of the heat exchanger 10 (refer to FIG. 1 ) that is the third direction X of the flat tube 2. Figure 2 ) is set, and the flat tube 2 will not be inserted into the connecting flow path 5. In addition, at least one connecting flow path 5 is set in the header 11.

[0136] Effects of Implementation 4

[0137] As described above, in the header 11 of the fourth embodiment, by providing the connecting flow path 5 in which the flat tubes 2 are not inserted, and connecting the communication paths 22a and 22b of the two regions 41 and 42, a flow of the refrigerant having a faster flow rate than the insertion portion 23 is formed. Thus, in the header 11 configured eccentrically to one region 41, for example, stirring of the refrigerant in the communication path 22b located in the other region 42 is promoted by the refrigerant flowing in the connecting flow path 5, thereby improving the distribution improvement effect and improving the heat exchanger performance.

[0138] Implementation method 5

[0139] Next, the heat exchanger 10 according to the fifth embodiment will be described. Fig.32 Schematic diagram showing a horizontal cross section of the header 11 in the heat exchanger 10 of Embodiment 5. Embodiment 5 changes a portion of the header 11 of Embodiment 1, and the structure of the heat exchanger 10 is the same as that of Embodiment 1, so the description is omitted, and the same or corresponding portions as those of Embodiment 1 are marked with the same reference numerals as those of Embodiment 1.

[0140] The header 11 of the heat exchanger 10 of the fifth embodiment does not connect at least a part of the communication path 22a and the communication path 22b to the insertion portion 23. The communication path 22a is located in one of the two regions 41 and 42 obtained by dividing the flow path 2 by the center plane 100 of the flat tube 2, and the communication path 22b is located in the other of the two regions 41 and 42. In other words, the header 11 is provided with the insertion portion 23a, and the insertion portion 23a is not directly connected to the communication path 22a located in one region 41 and the communication path 22b located in the other region 42, for example, the communication path 22a in the one region 41, and is blocked.

[0141] Effects of Implementation 5

[0142] As described above, in the header 11 of the fifth embodiment, the heat exchanger 10 (see Figure 1 The heat exchanger performance is improved by designing the distribution of the two-phase refrigerant corresponding to the air volume distribution of ventilation (eg, etc.). In addition, the insertion portion 23a that is not connected to the communication path 22a located in one area 41 can be connected to the communication path 22b located in another area 42.

[0143] Implementation 6

[0144] Next, the heat exchanger 10 according to Embodiment 6 will be described. Fig.33 Schematic diagram showing a horizontal cross section of the header 11 in the heat exchanger 10 of Embodiment 6. Embodiment 6 changes a part of the header 11 of the heat exchanger 10. The structure of the heat exchanger 10 is the same as that of Embodiment 1, so the description is omitted, and the same or corresponding parts as those of Embodiment 1 are marked with the same reference numerals as those of Embodiment 1.

[0145] The header 11 of the heat exchanger 10 of the sixth embodiment is as follows: Fig.33 As shown, the header 11 is provided with a first heat transfer tube group 51 on the upstream side of the flow path 21 and a second heat transfer tube group 52 on the downstream side of the flow path 21. In addition, the header 11 of the sixth embodiment has a first refrigerant inlet 24a and a second refrigerant inlet 24b as two different refrigerant inlets. The first refrigerant inlet 24a is connected to the communication path 22a arranged in one area 41. The second refrigerant inlet 24b is connected to the communication path 22b of another area 42. The flow path diameter of the second refrigerant inlet 24b is smaller than that of the first refrigerant inlet 24a.

[0146] In addition, a part or all of the flow path 21 connected to the first heat conduction pipe group 51 and the second heat conduction pipe group 52 is regarded as the header 31. In this case, observe Fig.33In the cross section of the first direction Y (not shown) of the horizontal cross section of the flow path 21 of the collecting pipe 31 shown, the diameter of a portion of the flow path around the second refrigerant inlet 24b of the connecting path 22b located between the first heat conduction tube group 51 and the second heat conduction tube group 52 is smaller than the diameter at other positions.

[0147] Effects of Implementation 6

[0148] As described above, in the header 11 of the sixth embodiment, the first refrigerant inlet 24a and the second refrigerant inlet 24b are configured so that the flow path diameter of the second refrigerant inlet 24b connected to the communication path 22b having a smaller flow path cross-sectional area is smaller than the flow path diameter of the first refrigerant inlet 24a connected to the communication path 22a having a larger flow path cross-sectional area. As a result, the refrigerant flow rate flowing in the communication path 22b is reduced, and the sensitivity of the gas-liquid two-phase distribution to the inertial force having a positive correlation with the refrigerant mass velocity is reduced, and the heat exchanger performance can be improved in a wide operating power range.

[0149] Fig.34 It is a schematic diagram showing a horizontal cross section of the header 11 showing a modification of the heat exchanger 10 according to the sixth embodiment. Fig.35 FIG. 2 is a schematic diagram showing a horizontal cross section of the header 11, showing a modified example of the heat exchanger 10 of the sixth embodiment. Fig.34 as well as Fig.35 As shown in FIG. 1 , the flow path liquid of the second refrigerant inlet 24b may also be set to "0". Fig.34 In the embodiment, the second refrigerant inlet 24b may be removed. Fig.35 In the embodiment, the partition portion 29 may be provided instead of the second refrigerant inlet 24b, so that the refrigerant flow rate flowing through the communication path 22b of the header 11 is set to "0".

[0150] Fig.36 FIG. 2 is a schematic diagram showing a horizontal cross section of the header 11, showing a modified example of the heat exchanger 10 of the sixth embodiment. Fig.36 As shown, the communication passages 22a and 22b may be formed integrally with the communication passage of the header 30 of the upstream heat exchanger.

[0151] Fig.37 FIG. 2 is a schematic diagram showing a horizontal cross section of the header 11, showing a modified example of the heat exchanger 10 of the sixth embodiment. Fig.37 As shown, a part of the flat tubes 2 connected to the header 11 may be set as the flat tubes 2 constituting the first heat transfer tube group 51, so that at least one flat tube on the most upstream side of the refrigerant flow functions as the second refrigerant inlet 24b. With this structure, the refrigerant can be supplied to the communication path 22b while reducing the inertial force in the second direction Z, thereby improving the performance improvement effect obtained by the diffusion of gas and liquid in the communication path 22b.

[0152] In addition, the case where the heat transfer pipe group of the heat exchanger 10 is constituted by the first heat transfer pipe group 51 and the second heat transfer pipe group 52 is described here, but the present invention is not limited thereto. For example, the heat transfer pipe group of the heat exchanger 10 may be constituted by three or more heat transfer pipe groups, and the above-mentioned structure may be different in each of the two heat transfer pipe groups.

[0153] Description of Reference Numerals

[0154] 1. fin; 2. flat tube; 3. refrigerant inlet; 4. contraction hole; 5. connecting flow path; 6. porous body; 7. partition; 10. heat exchanger; 11. header; 12. refrigerant piping; 13. outdoor fan; 14. compressor; 15. four-way valve; 16. indoor heat exchanger; 17. throttling device; 18. bypass flow path; 19. throttling device; 20. refrigerant flow path; 21. flow path; 22. connecting path; 22a. connecting path; 22b. connecting path; 23. insertion part; 23a. insertion part; 24. refrigerant inlet; 24a. first refrigerant inlet; 24b. second refrigerant inlet; 25. connecting path; 26. connecting path; 27. wall surface; 28. flow path wall surface; 29. ​​partition; 31. header ; 41. area; 42. area; 43. area; 45. area; 51. first heat-conducting pipe group; 52. second heat-conducting pipe group; 61. liquid-based refrigerant; 62. gas-based refrigerant; 63. liquid refrigerant; 64. gas refrigerant; 80. cover member; 81. cover member; 90. penetration portion; 91. plate-like member; 92. plate-like member; 93. plate-like member; 94. plate-like member; 100. center plane; 101. center plane in the short side direction; 200. air-conditioning device; 201. outdoor unit; 202. indoor unit; 501. header; 502. flat tube; 520. refrigerant flow path; 521. flow path; 522. connecting path; 523. insertion portion; BA, expansion portion; CA, reduction portion.

Claims

1. A heat exchanger, comprising a header and a plurality of flat tubes, wherein the plurality of flat tubes are arranged to extend in a first direction, and the cross section of the plurality of flat tubes in a second direction orthogonal to the first direction is flat, and the plurality of flat tubes are arranged to be spaced apart from each other in the second direction, and the header is arranged to extend in the second direction to connect the ends of the adjacent flat tubes in the first direction to each other, wherein: The header has a flow path formed inside for the refrigerant to flow. The flow path is formed with a partition portion, an insertion portion, a first communication path, and a second communication path, The partitions are disposed between adjacent flat tubes, respectively, to close at least a portion of the flow path between the flat tubes, thereby preventing the refrigerant from flowing in the second direction. The insertion portion is formed by being sandwiched between the adjacent partitions, is a space for the refrigerant to flow in a third direction intersecting the first direction and the second direction of each of the flat tubes, and is a space for each of the flat tubes to be inserted. The first communication passage connects one side of each of the adjacent insertion sections in the third direction to each other. The second communication passage connects the other sides of the adjacent insertion sections in the third direction to each other. The cross-sectional area of ​​the first communication path perpendicular to the second direction is larger than the cross-sectional area of ​​the second communication path perpendicular to the second direction. A first refrigerant inlet that allows the refrigerant to flow into the header and is connected to the flow path is formed in the first communication path.

2. The heat exchanger according to claim 1, wherein: A width of the insertion portion in the second direction at least at a connection portion with the second communication path is smaller than a width of the partition portion in the second direction.

3. The heat exchanger according to claim 1 or 2, wherein: Each of the flat tubes is arranged to extend in the vertical direction. The header is provided at least at one of the ends of each of the flat tubes located on the upper side or the lower side in the first direction.

4. The heat exchanger according to claim 1 or 2, wherein: When the flow path cross-sectional area of ​​the first communication path in the first direction is S1 and the flow path cross-sectional area of ​​the second communication path in the first direction is S2, a quotient obtained by dividing S2 by S1 is greater than 0.15 and less than 0.

8.

5. The heat exchanger according to claim 1 or 2, wherein: The flat tubes are inserted into the header so as to protrude only toward the second communication passage when viewed from the first direction.

6. The heat exchanger according to claim 1 or 2, wherein: The header is provided with a flow contraction hole, and the flow contraction hole is provided only in the first communication passage and is provided at a connection portion between the first communication passage and the insertion portion.

7. The heat exchanger according to claim 1 or 2, wherein: A connecting flow path is formed in the header, the connecting flow path being provided in at least one of the partitions and connecting the first communicating path and the second communicating path.

8. The heat exchanger according to claim 1 or 2, wherein: A portion of the first communication passage or the second communication passage of the header is blocked from the insertion portion.

9. The heat exchanger according to claim 1 or 2, wherein: A different heat exchanger is also provided on the upstream side in the flow direction of the refrigerant. In the header connected to the header where the plurality of flat tubes included in the different heat exchangers merge via the first communication passage, The communication passage having a larger flow passage cross-sectional area in the first direction is set as the first communication passage, The connecting passage having a smaller flow passage cross-sectional area in the first direction is set as the second connecting passage, The flow path diameter of the second refrigerant inlet of the header connecting the second communication path and the different heat exchanger is smaller than the flow path diameter of the first refrigerant inlet of the header connecting the first communication path and the different heat exchanger, or they are not connected.

10. The heat exchanger according to claim 9, wherein: In the header, at least one of the flat tubes located on the upstream side in the refrigerant flow direction among the flat tubes functions as the second refrigerant inlet.

11. An air conditioning device, wherein: The air conditioning device includes a heat pump type refrigerant circuit having at least a compressor, a condenser, an expansion valve, and an evaporator, and the heat exchanger according to any one of claims 1 to 10 is mounted as the condenser or the evaporator.

12. The air conditioning device according to claim 11, wherein: The refrigerant is R32 refrigerant containing at least olefin-based refrigerant, propane, and dimethyl ether, or a refrigerant having a gas density smaller than that of R410A refrigerant.

Images