WO2020012549A1

WO2020012549A1 - Heat exchanger, heat exchange device, heat exchanger unit, and refrigeration system

Info

Publication number: WO2020012549A1
Application number: PCT/JP2018/025982
Authority: WO
Inventors: 龍一永田; 前田　剛志; 真哉東井上; 石橋　晃
Original assignee: 三菱電機株式会社
Priority date: 2018-07-10
Filing date: 2018-07-10
Publication date: 2020-01-16
Also published as: JPWO2020012549A1

Abstract

A heat exchanger comprising: a first heat transfer conduit; and a plurality of first heat exchange parts arranged parallel to each other and each having an upstream airflow upstream fin extending from the upstream airflow-side end section of the first heat transfer conduit to the upstream airflow-side and a downstream airflow-side fin extending from the downstream airflow-side end section of the first heat transfer conduit to the downstream airflow-side. In a cross-section intersecting the extension direction of the first heat transfer conduit, the length L1 of the upstream airflow-side fin and the length L2 of the downstream airflow-side fin fulfil the relationship L1 > L2.

Description

Heat exchanger, heat exchange device, heat exchanger unit and refrigeration cycle device

The present invention relates to a heat exchanger having a plurality of heat transfer tubes, a heat exchange device, a heat exchanger unit, and a refrigeration cycle device.

Patent Document 1 describes a finless heat exchanger for an air conditioner including a plurality of flat tubes. In this air conditioner finless heat exchanger, the plurality of flat tubes are arranged such that the major axis direction of each flat tube is substantially parallel to the flow of air. The plurality of flat tubes are arranged in a line in a direction intersecting with the direction of air flow at equal intervals.

JP 2009-14501 A

In a finless heat exchanger as described in Patent Document 1, in order to secure a heat transfer area with air, heat transfer tubes are arranged at a higher density than a heat exchanger having heat transfer fins. Often. When the heat transfer tubes are arranged at a high density, when the finless heat exchanger operates as an evaporator, the air passage is likely to be blocked by frost. Therefore, the finless heat exchanger has a problem that the performance of the heat exchanger may be rapidly reduced due to blockage of the air passage.

The present invention has been made in order to solve the above-described problems, and has been made to provide a heat exchanger, a heat exchange device, a heat exchanger unit, and a refrigeration cycle device that can prevent a sharp decrease in heat exchanger performance. The purpose is to provide.

A heat exchanger according to the present invention includes a first heat transfer tube, a windward fin extending from the windward end of the first heat transfer tube to the windward side, and a leeward side from the leeward end of the first heat transfer tube. An extended leeward fin, each having a plurality of first heat exchange portions arranged in parallel with each other, and having a cross section that intersects with a direction in which the first heat transfer tube extends, a length of the leeward fin. L1 and the length L2 of the leeward fin satisfy the relationship of L1> L2.
A heat exchange device according to the present invention includes a first heat exchanger and a second heat exchanger disposed downstream of the first heat exchanger, wherein the first heat exchanger is configured according to the present invention. In the heat exchanger, the second heat exchanger includes a plurality of second heat exchange units each having a second heat transfer tube and arranged in parallel with each other.
A heat exchanger unit according to the present invention includes the heat exchanger according to the present invention, and a blower that blows air to the heat exchanger.
A refrigeration cycle device according to the present invention includes the heat exchanger unit according to the present invention.

According to the present invention, since the length L1 of the windward fin can be increased, the temperature difference between the temperature of the leading edge of the windward fin and the temperature of the air flowing into the heat exchanger can be reduced. Thereby, since the amount of frost formed on the first heat exchange unit can be reduced, the thickness of frost adhering to the surface of the first heat exchange unit can be reduced. Therefore, according to the present invention, it is possible to prevent the heat exchanger performance of the heat exchanger from suddenly lowering due to blockage of the air passage due to frost.

FIG. 2 is a perspective view illustrating a configuration of a heat exchanger 20 according to Embodiment 1 of the present invention. FIG. 2 is a cross-sectional view illustrating a configuration of a heat exchanger 20 according to Embodiment 1 of the present invention. FIG. 2 is an exploded perspective view showing a configuration in which a part of the heat exchanger 20 according to Embodiment 1 of the present invention is exploded. 5 is a graph illustrating a relationship between a position in a flow direction of air and a temperature of the heat exchanger 20 according to Embodiment 1 of the present invention. FIG. 9 is a perspective view illustrating a configuration of a heat exchange device 50 according to Embodiment 2 of the present invention. FIG. 7 is a cross-sectional view illustrating a configuration of a heat exchange device 50 according to Embodiment 2 of the present invention. FIG. 9 is a perspective view illustrating a configuration of a heat exchange device 50 according to Embodiment 3 of the present invention. It is a sectional view showing the composition of heat exchange device 50 concerning Embodiment 3 of the present invention. It is a circuit diagram showing a configuration of a refrigeration cycle apparatus 100 according to Embodiment 4 of the present invention.

Embodiment 1 FIG.
A heat exchanger according to Embodiment 1 of the present invention will be described. FIG. 1 is a perspective view showing a configuration of the heat exchanger 20 according to the present embodiment. FIG. 2 is a cross-sectional view illustrating a configuration of the heat exchanger 20 according to the present embodiment. FIG. 2 shows a configuration in which a vertical intermediate portion of the heat exchanger 20 is cut along a horizontal plane. FIG. 3 is an exploded perspective view showing a configuration in which a part of the heat exchanger 20 according to the present embodiment is disassembled. In FIGS. 1 to 3 and FIGS. 5 to 8 described later, the following coordinate systems are defined. That is, the z axis is set in parallel with the direction of gravity, and the upper side is set as the + z direction. The x axis is set in a direction perpendicular to the z axis and along the flow of air, and the windward side is defined as a + x direction. Further, the y axis is set in a direction orthogonal to both the z axis and the x axis. An xy plane parallel to both the x axis and the y axis is a horizontal plane.

As shown in FIGS. 1 to 3, the heat exchanger 20 includes a plurality of heat exchange units 35 arranged in parallel with each other, a header 21 arranged at one end of the plurality of heat exchange units 35, and a plurality of heat exchange units. And a header 22 disposed on the other end side of the heat exchange section 35. The plurality of heat exchange units 35 are sandwiched between the header 21 and the header 22 from above and below. Each of the plurality of heat exchange units 35 includes one heat transfer tube 30, one leeward fin 31 provided on the leeward side of the heat transfer tube 30, and one leeward fin provided on the leeward side of the heat transfer tube 30. 32. 1 and 3 show ten heat exchange units 35, and FIG. 2 shows nine heat exchange units 35. The heat exchanger 20 is an air heat exchanger that exchanges heat between the internal fluid flowing through the heat transfer tube 30 and air. In FIGS. 1 to 3, the direction of air flow is indicated by white arrows. The direction of air flow is generally in the −x direction. When the heat exchanger 20 forms a part of a refrigeration cycle device, a refrigerant is used as an internal fluid flowing through the heat transfer tube 30.

In each of the plurality of heat exchange units 35, the heat transfer tube 30, the windward fin 31, and the leeward fin 32 may be integrally formed using the same material, or may be formed as separate members. Each of the heat transfer tube 30, the windward fin 31, and the leeward fin 32 is desirably formed using a metal material having high thermal conductivity such as aluminum, copper, or brass.

In the present embodiment, since the vertical flow type heat exchanger 20 is illustrated, the heat exchanger 20 is configured such that each of the plurality of heat transfer tubes 30 extends in the vertical direction along the z-axis direction, that is, the direction of gravity. is set up. The plurality of heat transfer tubes 30 are arranged in the y-axis direction so as to be substantially perpendicular to both the gravity direction and the air flow direction. Hereinafter, the direction in which each of the plurality of heat transfer tubes 30 extends may be referred to as the direction in which the heat transfer tubes 30 extend. The direction in which the plurality of heat transfer tubes 30 are arranged in parallel may be referred to as the direction in which the plurality of heat transfer tubes 30 are arranged in parallel. The parallel direction of the plurality of heat transfer tubes 30 usually matches the longitudinal direction of the header 21 and the longitudinal direction of the header 22. Since the plurality of heat transfer tubes 30 are arranged as described above, each of the plurality of heat exchange portions 35 extends in the up-down direction along the z-axis direction. Further, the plurality of heat exchange units 35 are arranged in parallel in the y-axis direction.

In the present embodiment, a flat tube having a flat cross section in one direction is used as the heat transfer tube 30. Hereinafter, the major axis direction of the flat tube in a cross section perpendicular to the extending direction of the flat tube may be simply referred to as the major axis direction of the flat tube. When a flat tube is used as the heat transfer tube 30, the long diameter direction of the flat tube may be referred to as the long diameter direction of the heat transfer tube 30. The heat transfer tubes 30 are provided such that the major diameter direction of the heat transfer tubes 30 is parallel to the air flow direction. A plurality of fluid passages 40 through which the internal fluid flows are formed inside the heat transfer tube 30. The plurality of fluid passages 40 of each heat transfer tube 30 are arranged in parallel along the longitudinal direction of the heat transfer tube 30.

熱 The heat transfer tube 30 has a windward end portion 30a located on the leeward side and a leeward end portion 30b located on the leeward side as longitudinal ends of the heat transfer tube 30. The windward fins 31 extend from the windward end 30a to the windward side along the major axis direction of the heat transfer tubes 30 in a cross section perpendicular to the direction in which the heat transfer tubes 30 extend. The windward fins 31 also extend in the direction in which the heat transfer tubes 30 extend. The windward fins 31 have, for example, a rectangular flat plate shape having long sides along the direction in which the heat transfer tubes 30 extend. When a flat tube is used as the heat transfer tube 30, the plate thickness of the windward fin 31 is smaller than the minor diameter of the flat tube. When a circular tube is used as the heat transfer tube 30, the thickness of the windward fin 31 is smaller than the outer diameter of the circular tube. The fluid passage 40 is not formed in the windward fin 31.

(4) The leeward fins 32 extend leeward along the major axis direction of the heat transfer tube 30 from the leeward end 30b in a cross section perpendicular to the direction in which the heat transfer tube 30 extends. The leeward fins 32 also extend along the direction in which the heat transfer tubes 30 extend. The leeward fin 32 has, for example, a rectangular flat plate shape having a long side along the extending direction of the heat transfer tube 30. When a flat tube is used as the heat transfer tube 30, the plate thickness of the leeward fin 32 is smaller than the minor diameter of the flat tube. When a circular tube is used as the heat transfer tube 30, the plate thickness of the leeward fin 32 is smaller than the outer diameter of the circular tube. No fluid passage 40 is formed in the leeward fin 32.

Since the heat exchange unit 35 has the windward fins 31 and the leeward fins 32, the heat transfer area between the heat exchange unit 35 and the air can be increased, so that the heat exchanger performance of the heat exchanger 20 is improved. be able to. In this embodiment, the leeward fin 32 can be omitted.

ヘッダ As shown in FIG. 3, the header 22 has a plurality of insertion holes 23 into which the plurality of heat transfer tubes 30 are inserted. The plurality of insertion holes 23 are formed at substantially equal intervals at a formation pitch Ph1 along the longitudinal direction of the header 22. Here, the formation pitch Ph1 is a distance between the center portions of the two insertion holes 23 adjacent to each other in a direction perpendicular to both the extending direction of the heat transfer tube 30 and the major diameter direction of the heat transfer tube 30. Although not shown, the header 21 also has a plurality of insertion holes into which the plurality of heat transfer tubes 30 are inserted. The plurality of insertion holes of the header 21 are formed at substantially equal intervals along the longitudinal direction of the header 21 at a formation pitch Ph1.

The upper ends of the plurality of heat transfer tubes 30 are inserted into insertion holes of the header 21 and are joined to the header 21. Thereby, each of the plurality of heat exchange units 35 is connected to the header 21. The lower end of each of the plurality of heat transfer tubes 30 is inserted into the insertion hole 23 of the header 22 and is joined to the header 22. Thereby, each of the plurality of heat exchange units 35 is connected to the header 22.

間隙 A gap 33 is formed between two adjacent heat exchange sections 35 among the plurality of heat exchange sections 35 to be an air passage through which air flows. No heat transfer fin is provided between two adjacent heat exchange units 35 to connect the two heat exchange units 35. That is, the heat exchanger 20 is a so-called finless heat exchanger. Since no heat transfer fin is provided between two adjacent heat exchange units 35, the plurality of heat exchange units 35 are mechanically connected to each other only via the header 21 and the header 22. Further, the plurality of heat exchange units 35 are thermally connected to each other substantially only through the header 21 and the header 22.

The plurality of heat exchange units 35 are arranged at substantially equal intervals at an arrangement pitch Pf1 along the parallel direction of the heat transfer tubes 30. Thus, the heat transfer tubes 30, the windward fins 31, and the leeward fins 32 are also arranged at substantially the same interval at the same arrangement pitch as the arrangement pitch Pf1. The arrangement pitch Pf1 is equal to the distance between the center portions in the thickness direction of the two windward fins 31 adjacent to each other in the direction perpendicular to both the extending direction of the heat transfer tube 30 and the major diameter direction of the heat transfer tube 30. The arrangement pitch Pf1 of the heat exchange portions 35 is determined by the formation pitch Ph1 of the insertion hole 23, and is equal to the formation pitch Ph1 of the insertion hole 23 (Pf1 = Ph1). When manufacturing the heat exchanger 20, the arrangement pitch Pf1 of the heat exchange portions 35 can be easily adjusted by adjusting the formation pitch Ph1 of the insertion holes 23.

断面 In the cross section perpendicular to the extending direction of the heat transfer tube 30, the length L1 of the windward fin 31 and the length L2 of the leeward fin 32 satisfy the relationship of L1> L2. That is, the length L1 of the leeward fin 31 is longer than the length L2 of the leeward fin 32. In the cross section, the length L1 of the windward fin 31 is, for example, equal to or longer than the major diameter Lp of the heat transfer tube 30 (L1 ≧ Lp). In the cross section, the length L2 of the leeward fin 32 is shorter than the major diameter Lp of the heat transfer tube 30 (L2 <Lp).

Next, the operation of the heat exchanger 20 according to the present embodiment will be described. Here, the case where the heat exchanger 20 is used as an outdoor heat exchanger of a refrigeration cycle apparatus and a heating operation is performed will be described as an example. In this case, in the heat exchanger 20, heat exchange between the low-pressure refrigerant flowing through the heat transfer tube 30 and the outdoor air blown by the blower is performed via the heat transfer tube 30, the windward fin 31, and the leeward fin 32.

(4) If the surface temperature of the heat exchange unit 35 such as the heat transfer tube 30, the windward fin 31, and the leeward fin 32 is lower than the dew point temperature of the inflowing outdoor air, dew condensation occurs on the surface of the heat exchange unit 35. If the dew water generated by the dew condensation stays on the surface of the heat exchange unit 35, it causes an increase in the pressure loss of air. When the pressure loss of the air increases, the air flow rate of the air decreases, so that the heat exchanger performance of the heat exchanger 20 decreases. Therefore, it is desirable that the dew water generated on the surface of the heat exchange unit 35 be quickly drained to the outside of the heat exchanger 20.

If the surface temperature of the heat exchange unit 35 is 0 ° C. or less, frost adheres to the surface of the heat exchange unit 35. The attachment of the frost starts from the front edge on the windward side of the heat exchange unit 35 and gradually progresses to the leeward side of the heat exchange unit 35. When frost formation progresses and the amount of frost increases, the air passage of the heat exchanger 20 is blocked by the frost, and the pressure loss of air increases. For this reason, in the refrigeration cycle apparatus, a defrosting operation is performed to melt the frost attached to the heat exchanger 20. It is desirable that the molten water in which the frost has been melted by the defrosting operation is quickly drained to the outside of the heat exchanger 20 in order to prevent a decrease in the heat exchanger performance.

熱 The heat exchanger 20 of the present embodiment is installed such that the heat transfer tube 30, the windward fin 31, and the leeward fin 32 of the heat exchange unit 35 extend in parallel with the direction of gravity. Further, in the present embodiment, no heat transfer fin is provided between two adjacent heat exchange portions 35. For this reason, the dew condensation water or the molten water on the surface of the heat exchange unit 35 flows down the heat exchange unit 35 by its own weight and flows down, and is drained without being hindered by the heat transfer fins. Therefore, according to the present embodiment, the drainage performance of the heat exchanger 20 can be improved as compared with a conventional heat exchanger such as a cross-fin tube type, so that the heat exchanger performance of the heat exchanger 20 can be improved. Can be prevented from decreasing.

FIG. 4 is a graph showing the relationship between the position in the air flow direction of the heat exchanger 20 according to the present embodiment and the temperature. The horizontal axis represents a one-dimensional position in the air flow direction, and the vertical axis represents temperature. The position on the horizontal axis corresponds to the position of the heat exchange unit 35 shown below the horizontal axis. The white arrow below the horizontal axis indicates the direction of air flow. The position P1 corresponds to a position on the windward side of the heat exchange unit 35. That is, the temperature T1 at the position P1 corresponds to the representative temperature of the air before flowing into the heat exchanger 20. The position P2 corresponds to the position of the windward end of the windward fin 31. That is, the temperature T2 at the position P2 corresponds to the leading edge temperature of the windward fin 31. The position P3 corresponds to the position of the windward end 30a of the heat transfer tube 30. That is, the temperature T3 at the position P3 corresponds to the temperature of the windward end 30a of the heat transfer tube 30.

(4) As shown in FIG. 4, the leading edge temperature T2 of the windward fin 31 is higher than the temperature T3 of the windward end 30a of the heat transfer tube 30 (T2> T3). Therefore, the temperature difference ΔT1 between the representative temperature T1 of air and the leading edge temperature T2 of the windward fin 31 is larger than the temperature difference ΔT2 between the representative temperature T1 of air and the temperature T3 of the windward end 30a of the heat transfer tube 30. (ΔT1 <ΔT2). For this reason, in the heat exchange unit 35 provided with the windward fins 31, the temperature difference ΔT1 becomes smaller, and frost formation is less likely to occur than in the heat exchange unit 35 provided with no windward fins 31. Further, as the length of the windward fin 31 increases, the leading edge temperature T2 of the windward fin 31 approaches the representative temperature T1 of the air due to a decrease in the fin efficiency. That is, when the temperature of the inflowing air is constant, the temperature difference ΔT1 can be reduced by increasing the length of the windward fins 31, so that the amount of frost can be reduced. Therefore, by increasing the length of the windward fins 31, the thickness of the frost adhering to the surface of the heat exchange unit 35 per heat exchange amount can be reduced. In the present embodiment, since the length of the windward fins 31 can be lengthened, it is possible to prevent the wind path from being blocked due to frost formation, and to prevent a sharp decrease in heat exchanger performance. The length of the windward fin 31 is desirably set such that the temperature difference ΔT1 is equal to or less than half of the temperature difference ΔT2 (ΔT1 ≦ ΔT2 / 2).

As described above, the heat exchanger 20 according to the present embodiment includes the plurality of heat exchange units 35 arranged in parallel with each other. Each of the plurality of heat exchange sections 35 extends from the heat transfer tube 30, the windward fin 31 extending from the windward end 30 a of the heat transfer tube 30 to the windward side, and the leeward end from the leeward end 30 b of the heat transfer tube 30. Leeward fins 32. Here, the heat exchange unit 35 is an example of a first heat exchange unit. The heat transfer tube 30 is an example of a first heat transfer tube. In a cross section that intersects with the direction in which the heat transfer tubes 30 extend, the length L1 of the windward fin 31 and the length L2 of the leeward fin 32 satisfy the relationship of L1> L2.

According to this configuration, since the length L1 of the windward fin 31 can be increased, the temperature difference ΔT1 between the temperature T2 of the leading edge of the windward fin 31 and the temperature T1 of the air flowing into the heat exchanger 20 is determined. Can be smaller. Thereby, since the amount of frost on the heat exchange unit 35 can be reduced, the thickness of frost adhering to the surface of the heat exchange unit 35 can be reduced. Therefore, according to the present embodiment, it is possible to prevent the heat exchanger performance of the heat exchanger 20 from suddenly decreasing due to blockage of the air passage due to frost formation.

On the other hand, according to the present embodiment, since the length L2 of the leeward fin 32 can be reduced, the thickness of the heat exchanger 20 in the direction along the flow of air can be reduced. Therefore, according to the present embodiment, it is possible to prevent a sharp decrease in the heat exchanger performance of the heat exchanger 20 while suppressing an increase in the thickness dimension of the heat exchanger 20 in a direction along the flow of air. .

Further, in the heat exchanger 20 according to the present embodiment, between two adjacent heat exchange units 35 of the plurality of heat exchange units 35, heat transfer fins connecting the two heat exchange units 35 are provided. Not provided. According to this configuration, the condensed water or the molten water on the surface of the heat exchange unit 35 can be drained without being hindered by the heat transfer fins. Therefore, according to the present embodiment, since the drainage of the heat exchanger 20 can be improved, it is possible to prevent the heat exchanger performance of the heat exchanger 20 from deteriorating.

The heat exchanger 20 according to the present embodiment further includes a header 21 and a header 22 arranged at least on one end side of the plurality of heat exchange units 35. In the header 21 and the header 22, a plurality of insertion holes 23 into which one ends of the heat transfer tubes 30 included in the plurality of heat exchange portions 35 are inserted are formed at a predetermined formation pitch Ph1. The arrangement pitch Pf1 of the plurality of heat exchange units 35 is determined by the formation pitch Ph1. According to this configuration, when the heat exchanger 20 is manufactured, the arrangement pitch Pf1 of the heat exchange portions 35 can be easily adjusted by adjusting the formation pitch Ph1 of the insertion hole 23. Therefore, the degree of freedom of the arrangement pitch Pf1 of the heat exchange unit 35 can be increased.

Japanese Patent No. 4623083 describes a configuration in which a fin pitch is determined using a fin collar in a cross fin tube type heat exchanger. The fin collar is formed at a height corresponding to the fin pitch by bending or stretching the fin material. Therefore, if the fin material is thin, the formed fin collar may be broken. Therefore, when the fin pitch is determined using the fin collar, the fin pitch is limited by the thickness of the fin material.

On the other hand, in the present embodiment, the arrangement pitch Pf1 of the heat exchange portions 35 is determined by the formation pitch Ph1 of the insertion hole 23. Therefore, regardless of the thickness of the fin material, the arrangement pitch Pf1 of the heat exchange units 35, that is, the arrangement pitch of the windward fins 31 and the leeward fins 32 can be adjusted to a desired value.

では Furthermore, in the heat exchanger 20 according to the present embodiment, a flat tube is used as the heat transfer tube 30. In a cross section that intersects with the direction in which the heat transfer tubes 30 extend, the length L1 of the windward fins 31 is equal to or longer than the major diameter Lp of the heat transfer tubes 30. According to this configuration, since the temperature difference ΔT1 can be further reduced, the amount of frost on the heat exchanger 20 can be further reduced.

Embodiment 2 FIG.
A heat exchange device according to Embodiment 2 of the present invention will be described. FIG. 5 is a perspective view illustrating a configuration of the heat exchange device 50 according to the present embodiment. FIG. 6 is a cross-sectional view illustrating a configuration of the heat exchange device 50 according to the present embodiment. FIG. 6 shows a configuration in which a vertical intermediate portion of the heat exchange device 50 is cut along a horizontal plane. Note that components having the same functions and functions as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted. While the heat exchanger 20 of the first embodiment has a single-row configuration, the heat exchanger 50 of the present embodiment has two rows of heat exchangers along the flow of air. The heat exchange device 50 may include three or more rows of heat exchangers along the flow of air.

As shown in FIGS. 5 and 6, the heat exchange device 50 has the heat exchanger 20 of the first embodiment as a first-row heat exchanger arranged on the windward side. As described above, the heat exchanger 20 includes a plurality of heat exchange units 35 arranged in parallel with each other, a header 21 arranged at one end of the plurality of heat exchange units 35, and a plurality of heat exchange units 35. And a header 22 disposed at the other end of the head. The plurality of heat exchange units 35 are sandwiched between the header 21 and the header 22 from above and below. Each of the plurality of heat exchange sections 35 extends from the heat transfer tube 30, the windward fin 31 extending from the windward end 30 a of the heat transfer tube 30 to the windward side, and the leeward end from the leeward end 30 b of the heat transfer tube 30. Leeward fins 32. In a cross section that intersects with the direction in which the heat transfer tubes 30 extend, the length L1 of the windward fin 31 and the length L2 of the leeward fin 32 satisfy the relationship of L1> L2. The plurality of heat exchange units 35 are arranged at an arrangement pitch Pf1. The arrangement pitch Pf1 is determined by the formation pitch Ph1 of the insertion holes formed in the header 21 and the header 22.

{Circle around (2)} The heat exchanger 50 has the heat exchanger 60 as a second row of heat exchangers located downstream of the heat exchanger 20. The heat exchanger 60 includes a plurality of heat exchange units 75 arranged in parallel with each other, a header 61 arranged at one end of the plurality of heat exchange units 75, and an end arranged at the other end of the plurality of heat exchange units 75. And a header 62. The plurality of heat exchange parts 75 are sandwiched between the header 61 and the header 62 from above and below. Each of the plurality of heat exchange portions 75 extends to the leeward side from the heat transfer tube 70, the leeward fin 71 extending from the leeward end 70 a of the heat transfer tube 70 to the leeward side, and the leeward end 70 b of the heat transfer tube 70. Leeward fins 72. As the heat transfer tube 70, a flat tube or a circular tube is used. The heat transfer tube 70, the leeward fin 71, and the leeward fin 72 may be integrally formed, or may be formed as separate members. The direction in which the heat transfer tube 70 extends is parallel to the direction in which the heat transfer tube 30 extends.

In the cross section that intersects with the direction in which the heat transfer tubes 30 and the heat transfer tubes 70 extend, the length L3 of the windward fin 71 and the length L4 of the leeward fin 72 are all equal to the length L1 of the windward fin 31 of the heat exchanger 20. (L3 <L1 and L4 <L1). The length L3 of the leeward fin 71 and the length L4 of the leeward fin 72 are, for example, equal to the length L2 of the leeward fin 32 of the heat exchanger 20 (L3 = L4 = L2). The plurality of heat exchange units 75 are arranged at the arrangement pitch Pf2. The arrangement pitch Pf2 is determined by the formation pitch of the insertion holes formed in the header 61 and the header 62.

配置 The arrangement pitch Pf1 of the heat exchange unit 35 is equal to the arrangement pitch Pf2 of the heat exchange unit 75 (Pf1 = Pf2). When viewed along the flow of air, the plurality of heat exchange units 35 and the plurality of heat exchange units 75 are arranged to be shifted from each other by about a half pitch.

In the present embodiment, the header 21 and the header 61 for each column are separated from each other, but the header 21 and the header 61 may be integrated. Further, in the present embodiment, the header 22 and the header 62 for each column are separated from each other, but the header 22 and the header 62 may be integrated.

(4) When the surface temperature of the heat exchange unit 35 and the heat exchange unit 75 is 0 ° C. or less, frost adheres to the surfaces of the heat exchange unit 35 and the heat exchange unit 75. Adhesion of frost starts from the front edge of the leeward side of the heat exchange unit 35 in the first row of the heat exchangers 20 arranged on the leeward side, and gradually becomes the leeward side of the heat exchange unit 35 and the second and subsequent rows. To the heat exchange section 75 of the heat exchanger 60 of FIG. In the present embodiment, since the length L1 of the windward fin 31 of the heat exchange unit 35 in the first row of heat exchangers 20 can be increased, the leading edge temperature of the windward fin 31 and the heat exchanger 20 The temperature difference from the inflowing air temperature can be reduced. Thus, not only the amount of frost formed on the heat exchange unit 35 can be reduced, but also the amount of frost formed on the heat exchange unit 75 can be reduced. Therefore, the thickness of the frost adhering to the surfaces of the heat exchange unit 35 and the heat exchange unit 75 can be reduced.

As described above, the heat exchange device 50 according to the present embodiment includes the heat exchanger 20 and the heat exchanger 60 disposed downstream of the heat exchanger 20. The heat exchanger 20 is the heat exchanger 20 according to the first embodiment. The heat exchanger 60 includes a plurality of heat exchange sections 75 each having a heat transfer tube 70 and arranged in parallel with each other. Here, the heat exchanger 20 is an example of a first heat exchanger. The heat exchanger 60 is an example of a second heat exchanger. The heat exchange section 75 is an example of a second heat exchange section. The heat transfer tube 70 is an example of a second heat transfer tube.

According to this configuration, in the heat exchanger 20 arranged on the windward side of the heat exchange device 50, the length L1 of the windward fins 31 can be increased, so that the heat exchanger 20 and the heat exchanger 60 The amount of frost can be reduced. Therefore, according to the present embodiment, it is possible to prevent a rapid decrease in the heat exchanger performance of heat exchanger 50 due to blockage of the air passage. On the other hand, according to the present embodiment, since the length L2 of the leeward fins 32 of the heat exchanger 20 can be reduced, the heat exchanger 20 and the heat exchange device 50 in the direction along the flow of air can be reduced. The thickness dimension can be reduced. Therefore, according to the present embodiment, it is possible to prevent a rapid decrease in the heat exchanger performance of the heat exchange device 50 while suppressing an increase in the thickness of the heat exchange device 50 in the direction along the flow of air. .

Further, in the heat exchange device 50 according to the present embodiment, between two adjacent heat exchange units 35 of the plurality of heat exchange units 35, heat transfer fins connecting the two heat exchange units 35 are provided. Not provided. No heat transfer fins connecting the two heat exchange units 75 are provided between two adjacent heat exchange units 75 among the plurality of heat exchange units 75. That is, each of the heat exchanger 20 and the heat exchanger 60 is a so-called finless heat exchanger. According to this configuration, the condensed water or the molten water on the surfaces of the heat exchange unit 35 and the heat exchange unit 75 can be drained without being hindered by the heat transfer fins. Therefore, according to the present embodiment, since the drainage performance of the heat exchange device 50 can be improved, the deterioration of the heat exchanger performance of the heat exchange device 50 can be prevented.

Further, the heat exchange device 50 according to the present embodiment includes a header 21 and a header 22 arranged on at least one end of the plurality of heat exchange units 35, and a header arranged on at least one end of the plurality of heat exchange units 75. 61 and a header 62. In the header 21 and the header 22, a plurality of insertion holes 23 into which one ends of the heat transfer tubes 30 included in the plurality of heat exchange portions 35 are inserted are formed at a predetermined pitch. In the header 61 and the header 62, a plurality of insertion holes into which one ends of the heat transfer tubes 70 included in the plurality of heat exchange portions 75 are inserted are formed at a predetermined pitch. The arrangement pitch Pf1 of the plurality of heat exchange units 35 is determined by the formation pitch of the insertion holes 23 formed in the header 21 and the header 22. The arrangement pitch Pf2 of the plurality of heat exchange units 75 is determined by the formation pitch of the insertion holes formed in the header 61 and the header 62. According to this configuration, when manufacturing the heat exchanger 20 and the heat exchanger 60 of the heat exchange device 50, the arrangement pitch Pf1 of the heat exchange unit 35 and the arrangement pitch Pf2 of the heat exchange unit 75 can be easily adjusted. Therefore, the degree of freedom of the arrangement pitch Pf1 of the heat exchange units 35 and the arrangement pitch Pf2 of the heat exchange units 75 can be increased.

Embodiment 3 FIG.
A heat exchange device according to Embodiment 3 of the present invention will be described. FIG. 7 is a perspective view showing a configuration of the heat exchange device 50 according to the present embodiment. FIG. 8 is a cross-sectional view illustrating a configuration of the heat exchange device 50 according to the present embodiment. FIG. 8 illustrates a configuration in which a vertical intermediate portion of the heat exchange device 50 is cut along a horizontal plane. Note that components having the same functions and functions as those of the first or second embodiment are denoted by the same reference numerals, and description thereof is omitted. In the heat exchange device 50 of the present embodiment, the arrangement pitch Pf1 of the heat exchange units 35 in the first row heat exchanger 20 and the arrangement pitch Pf2 of the heat exchange units 75 in the second row heat exchanger 60 are different from each other. It differs from the heat exchange device 50 of the second embodiment in different points.

As shown in FIGS. 7 and 8, the arrangement pitch Pf1 of the heat exchange units 35 in the first-row heat exchanger 20 is wider than the arrangement pitch Pf2 of the heat exchange units 75 in the second-row heat exchanger 60. (Pf1> Pf2). The arrangement pitch Pf1 of the heat exchange portions 35 is determined by the formation pitch of the insertion holes formed in the header 21 and the header 22. The arrangement pitch Pf2 of the heat exchange portions 75 is determined by the formation pitch of the insertion holes formed in the header 61 and the header 62. The plurality of heat exchange sections 35 and the plurality of heat exchange sections 75 are arranged so as not to overlap each other as much as possible when viewed along the flow of air.

As described above, in the heat exchange device 50 according to the present embodiment, the arrangement pitch Pf1 of the plurality of heat exchange units 35 and the arrangement pitch Pf2 of the plurality of heat exchange units 75 satisfy the relationship of Pf1> Pf2. I have. According to this configuration, the arrangement pitch Pf1 of the heat exchangers 20 in the first row is wider than the arrangement pitch Pf2 of the heat exchangers 60 in the second row, so the heat exchange amount in the heat exchanger 20 in the first row Can be relatively reduced. Thereby, frost can be more uniformly adhered to the surface of the heat exchange unit 35 of the heat exchanger 20 and the surface of the heat exchange unit 75 of the heat exchanger 60. For this reason, the thickness of the frost adhering to the heat exchanger 20 and the heat exchanger 60 can be prevented from locally increasing. Therefore, according to the present embodiment, it is possible to prevent the air passage from being blocked due to frost, and to prevent a rapid decrease in the performance of the heat exchanger.

Embodiment 4 FIG.
A heat exchanger unit and a refrigeration cycle device according to Embodiment 4 of the present invention will be described. FIG. 9 is a circuit diagram showing a configuration of a refrigeration cycle apparatus 100 according to the present embodiment. In the present embodiment, an air conditioner is exemplified as refrigeration cycle device 100. As shown in FIG. 9, the refrigeration cycle apparatus 100 has a refrigeration cycle circuit 10 for circulating a refrigerant. The refrigeration cycle circuit 10 has a configuration in which a compressor 11, a four-way valve 12, an outdoor heat exchanger 13, an expansion valve 14, and an indoor heat exchanger 15 are connected in a ring through a refrigerant pipe. In addition, the refrigeration cycle apparatus 100 includes a blower 16 that blows air to the outdoor heat exchanger 13 and a blower 17 that blows air to the indoor heat exchanger 15. In the refrigeration cycle apparatus 100, the compressor 11 is driven to execute a refrigeration cycle in which the refrigerant circulates through the refrigeration cycle circuit 10 while changing phases. In the outdoor heat exchanger 13, heat exchange between the air blown by the blower 16 and the refrigerant as the internal fluid is performed. In the indoor heat exchanger 15, heat exchange between the air blown by the blower 17 and the refrigerant as the internal fluid is performed.

冷媒 As a refrigerant to be charged into the refrigeration cycle circuit 10, a refrigerant such as R410A, R32, or HFO-1234yf can be used. As the refrigerating machine oil used for the compressor 11, various types of refrigerating machine oils such as mineral oils, alkylbenzene oils, ester oils, ether oils, and fluorine oils can be used regardless of whether or not they are compatible with the refrigerant. it can.

The refrigeration cycle device 100 has an outdoor unit 110 and an indoor unit 120. The outdoor unit 110 houses a compressor 11, a four-way valve 12, an outdoor heat exchanger 13, an expansion valve 14, and a blower 16. The indoor unit 120 houses the indoor heat exchanger 15 and the blower 17. Both the outdoor unit 110 and the indoor unit 120 are heat exchanger units that house at least a heat exchanger.

The indoor heat exchanger 15 uses the heat exchanger 20 of the first embodiment or the heat exchange device 50 of the second or third embodiment. When the heat exchanger 20 of Embodiment 1 is used for the indoor heat exchanger 15, the indoor heat exchanger 15 is installed in the indoor unit 120 such that each of the plurality of heat transfer tubes 30 extends in the vertical direction. . When the heat exchange device 50 according to Embodiment 2 or 3 is used for the indoor heat exchanger 15, the indoor heat exchanger 15 includes a plurality of heat transfer tubes 30 and a plurality of heat transfer tubes 70 extending in the vertical direction. Thus, it is installed in the indoor unit 120. Similarly, the heat exchanger 20 of Embodiment 1 or the heat exchange device 50 of Embodiment 2 or 3 can be used for the outdoor heat exchanger 13.

動作 The operation of the refrigeration cycle apparatus 100 will be described by taking cooling operation as an example. The high-pressure gas refrigerant discharged from the compressor 11 flows into the outdoor heat exchanger 13 via the four-way valve 12. During the cooling operation, the outdoor heat exchanger 13 functions as a condenser. That is, in the outdoor heat exchanger 13, heat exchange between the refrigerant flowing inside and the outdoor air blown by the blower 16 is performed, and the heat of condensation of the refrigerant is radiated to the outdoor air. As a result, the gas refrigerant flowing into the outdoor heat exchanger 13 is condensed and becomes a high-pressure liquid refrigerant.

液 The liquid refrigerant flowing out of the outdoor heat exchanger 13 is decompressed by the expansion valve 14 and becomes a low-pressure two-phase refrigerant. The two-phase refrigerant flowing out of the expansion valve 14 flows into the indoor heat exchanger 15. During the cooling operation, the indoor heat exchanger 15 functions as an evaporator. That is, in the indoor heat exchanger 15, heat exchange is performed between the refrigerant flowing inside and the indoor air blown by the blower 17, and the heat of evaporation of the refrigerant is absorbed from the indoor air. As a result, the two-phase refrigerant flowing into the indoor heat exchanger 15 evaporates and becomes a low-pressure gas refrigerant. The gas refrigerant flowing out of the indoor heat exchanger 15 is sucked into the compressor 11 via the four-way valve 12. The gas refrigerant sucked into the compressor 11 is compressed into a high-pressure gas refrigerant. During the cooling operation, the above refrigeration cycle is continuously and repeatedly executed. Although the description is omitted, the flow direction of the refrigerant is switched by the four-way valve 12 during the heating operation, the outdoor heat exchanger 13 functions as an evaporator, and the indoor heat exchanger 15 functions as a condenser.

As described above, the heat exchanger unit according to the present embodiment includes the heat exchanger 20 according to the first embodiment, and the blower that blows air to the heat exchanger 20. The heat exchanger unit is, for example, the indoor unit 120 or the outdoor unit 110. The blower is, for example, the blower 17 or the blower 16. According to this configuration, it is possible to realize a heat exchanger unit including the heat exchanger 20 that can prevent a rapid decrease in heat exchanger performance due to blockage of the air passage.

In the heat exchanger unit according to the present embodiment, heat exchanger 20 is arranged such that heat transfer tube 30 extends in the up-down direction. The heat transfer tube 30 is an example of a first heat transfer tube. According to this configuration, the dew or melt water generated on the surface of the heat exchange unit 35 of the heat exchanger 20 flows down the heat exchange unit 35 by its own weight. Therefore, the drainage of the heat exchanger 20 can be improved in the heat exchanger unit.

The heat exchanger unit according to the present embodiment includes the heat exchange device 50 according to Embodiment 2 or 3, and a blower that blows air to the heat exchange device 50. The heat exchanger unit is, for example, the indoor unit 120 or the outdoor unit 110. The blower is, for example, the blower 17 or the blower 16. According to this configuration, it is possible to realize a heat exchanger unit including the heat exchange device 50 that can prevent a rapid decrease in heat exchanger performance due to blockage of the air passage.

In addition, in the heat exchanger unit according to the present embodiment, heat exchange device 50 is arranged such that heat transfer tubes 30 and heat transfer tubes 70 extend in the up-down direction. The heat transfer tube 30 is an example of a first heat transfer tube. The heat transfer tube 70 is an example of a second heat transfer tube. According to this configuration, it is possible to improve the drainage of the heat exchange device 50 in the heat exchanger unit.

冷凍 The refrigeration cycle apparatus 100 according to the present embodiment includes the heat exchanger unit according to the present embodiment. According to this configuration, it is possible to realize the refrigeration cycle apparatus 100 including the heat exchanger 20 or the heat exchange device 50 that can prevent a rapid decrease in the heat exchanger performance due to the blockage of the air passage.

In the first to fourth embodiments, the longitudinal flow type heat exchanger 20 in which the extending direction of the heat transfer tube 30 is parallel to the direction of gravity has been described as an example, but the present invention is not limited to this. The present invention can also be applied to a horizontal flow heat exchanger in which the extension direction of the heat transfer tube 30 is horizontal, or to a heat exchanger in which the extension direction of the heat transfer tube 30 is inclined with respect to both the gravity direction and the horizontal direction. .

In the first to fourth embodiments, the refrigerant is exemplified as the internal fluid flowing through the heat transfer tube 30 of the heat exchanger 20, but the present invention is not limited to this. As the internal fluid flowing through the heat transfer tube 30 of the heat exchanger 20, another fluid including a liquid such as water or brine may be used.

Further, in the first to fourth embodiments, the finless heat exchanger 20 in which no heat transfer fin is provided between two adjacent heat exchange units 35 has been described as an example. However, the present invention is not limited to this. Not limited. The present invention can also be applied to a heat exchanger in which a heat transfer fin is provided between two adjacent heat exchange units 35.

各 The above embodiments and modifications can be implemented in combination with each other.

10 refrigeration cycle circuit, 11 compressor, 12 four-way valve, 13 outdoor heat exchanger, 14 expansion valve, 15 indoor heat exchanger, 16, 17 blower, 20 heat exchanger, 21, 22 header, 23 insertion hole, 30 transmission Heat pipe, 30a windward end, 30b windward end, 31 windward fin, 32 windward fin, 33 gap, 35 heat exchanger, 40 fluid path, 50 heat exchanger, 60 heat exchanger, 61, 62 header , 70 heat transfer tube, 70a leeward end, 70b leeward end, 71 leeward fin, 72 leeward fin, 75 heat exchange unit, 100 refrigeration cycle device, 110 outdoor unit, 120 indoor unit.

Claims

A first heat transfer tube, a leeward fin extending from the leeward end of the first heat transfer tube to the leeward side, and a leeward fin extending from the leeward end of the first heat transfer tube to the leeward side, respectively. Comprising a plurality of first heat exchange units arranged in parallel with each other,
A heat exchanger wherein a length L1 of the leeward fin and a length L2 of the leeward fin satisfy a relationship of L1> L2 in a cross section intersecting with the extending direction of the first heat transfer tube.
2. The heat transfer fin according to claim 1, wherein no heat transfer fin that connects the two first heat exchange units is provided between two adjacent first heat exchange units among the plurality of first heat exchange units. 3. Heat exchanger.
Further comprising a header disposed on at least one end side of the plurality of first heat exchange units,
In the header, a plurality of insertion holes into which one ends of the first heat transfer tubes of each of the plurality of first heat exchange units are inserted are formed at a predetermined forming pitch,
The heat exchanger according to claim 1, wherein an arrangement pitch of the plurality of first heat exchange units is determined by the formation pitch.
A flat tube is used as the first heat transfer tube,
The length L1 of the windward fin in a cross section intersecting with the extending direction of the first heat transfer tube is equal to or longer than the major diameter of the first heat transfer tube. The heat exchanger as described.
A first heat exchanger, and a second heat exchanger disposed downstream of the first heat exchanger;
The first heat exchanger is the heat exchanger according to any one of claims 1 to 4,
The heat exchange device, wherein the second heat exchanger includes a plurality of second heat exchange units each having a second heat transfer tube and arranged in parallel with each other.
The heat exchange device according to claim 5, wherein the arrangement pitch Pf1 of the plurality of first heat exchange units and the arrangement pitch Pf2 of the plurality of second heat exchange units satisfy a relationship of Pf1> Pf2.
A heat exchanger according to any one of claims 1 to 4,
A blower for blowing air to the heat exchanger,
A heat exchanger unit comprising:
The heat exchanger unit according to claim 7, wherein the heat exchanger is arranged such that the first heat transfer tube extends in a vertical direction.
A heat exchange device according to claim 5 or 6,
A blower that blows air to the heat exchange device,
A heat exchanger unit comprising:
The heat exchanger unit according to claim 9, wherein the heat exchange device is arranged such that the first heat transfer tube and the second heat transfer tube extend in a vertical direction.
冷凍 A refrigeration cycle apparatus comprising the heat exchanger unit according to any one of claims 7 to 10.