WO2020066393A1

WO2020066393A1 - Heat exchanger

Info

Publication number: WO2020066393A1
Application number: PCT/JP2019/032956
Authority: WO
Inventors: 金子　智
Original assignee: サンデンホールディングス株式会社
Priority date: 2018-09-28
Filing date: 2019-08-23
Publication date: 2020-04-02
Also published as: JP2020056511A

Abstract

Provided is a heat exchanger with which it possible to increase heat-exchanging capacity without increasing the heat transfer surface area of heat-transfer fins. Heat-transfer fins 100 have a tube contact portion 101 which comes into surface contact with the flat surface of a flat tube 20, and the tube contact portion 101 has formed thereupon a heat transfer promotion portion 103 for promoting the transfer of heat to air, by varying the flow of air. As a result of this configuration, it is possible to promote the transfer of heat to air by varying the flow of air that flows in the vicinity of the flat tube 20.

Description

Heat exchanger

The present invention relates to, for example, a heat exchanger used for a vehicle air conditioner.

Conventionally, as this type of heat exchanger, a plurality of flat tubes through which the first fluid flows, a pair of headers to which both ends of the plurality of flat tubes are connected, and an outer surface of the flat tubes are provided in a waveform shape. There is known a heat transfer fin that has a heat transfer fin formed therein and exchanges heat between a first fluid flowing inside the flat tube and a second fluid flowing outside the flat tube (for example, see Patent Document 1).

Japanese Utility Model Publication No. 03-32944

The heat exchanger has a large heat transfer area for the second fluid via the heat transfer fins in order to improve the heat exchange efficiency between the first fluid and the second fluid. In the heat exchanger, when trying to increase the heat transfer area with respect to the second fluid, the external dimensions of the heat transfer fins may be increased, resulting in an increase in size. In the heat exchanger, when the heat transfer area for the second fluid is increased without increasing the outer dimensions of the heat transfer fins, the interval between the heat transfer fins is reduced. In the heat exchanger in which the interval between the heat transfer fins is reduced, the flow resistance of the second fluid is increased, and the flow rate of the second fluid is reduced, so that there is a possibility that the heat exchange capability is reduced or the noise is increased. is there.

An object of the present invention is to provide a heat exchanger that can increase the amount of heat exchange without increasing the heat transfer area of the heat transfer fins.

The heat exchanger according to the present invention includes a flat tube through which the first fluid flows, and a heat transfer fin provided on an outer surface of the flat tube and formed by bending a plate-like member. A heat exchanger for exchanging heat between a first fluid that flows and a second fluid that flows outside the flat tube, wherein the heat transfer fin has a tube contact portion that makes surface contact with the flat surface of the flat tube, Is formed with a heat transfer promoting portion that promotes heat transfer to the second fluid by changing the flow of the second fluid.

This changes the flow of the second fluid flowing in the vicinity of the flat tube, thereby promoting heat transfer to the second fluid in the vicinity of the flat tube.

According to the present invention, by changing the flow of the second fluid flowing in the vicinity of the flat tube, the transfer of heat to the second fluid in the vicinity of the flat tube can be promoted. The amount of exchanged heat can be increased without increasing the heat transfer area of the fin.

It is the whole heat exchanger perspective view showing one embodiment of the present invention. It is a top view of a heat exchanger. It is the figure which looked at the heat exchanger from the air distribution direction upstream. It is a side view of a heat exchanger. It is an exploded side view of a header and a header communication member. It is an exploded plan view of a header and a flat tube. It is a side sectional view explaining the distribution state of the air which flows through the gap of the heat transfer fin. It is the figure which looked at the heat exchanger which shows other embodiment of this invention from the upstream of the distribution direction of air. It is a side sectional view explaining the distribution state of the air which flows through the gap of the heat transfer fin.

FIGS. 1 to 7 show an embodiment of the present invention.

The heat exchanger 1 of the present invention is provided, for example, for each of a plurality of seats provided in a vehicle cabin of a vehicle, and blows out air whose temperature and humidity are adjusted toward an occupant seated on the seat. It is used for.

This vehicle air conditioner includes an air conditioning unit in which devices such as a compressor, a heat exchanger 1, and an expansion valve are integrally formed. The air-conditioning unit is arranged, for example, below the seat, at the ceiling of the vehicle compartment, at the door trim, under the armrest at the center in the width direction of the vehicle compartment, and the like. The air supplied from the air conditioning unit into the passenger compartment is blown out from outlets provided in the seat back, the seat surface, the lower part of the seat, the ceiling of the passenger compartment, the B pillar of the vehicle, and the like.

The heat exchanger 1 is used in an air conditioning unit as a condenser for condensing a refrigerant as a first fluid discharged from a compressor, and as an evaporator for evaporating a refrigerant decompressed by an expansion valve after flowing out of the condenser. Can be

As shown in FIG. 1, the heat exchanger 1 divides a plurality of heat exchange units 10 in a flow direction of air as a second fluid that exchanges heat with a refrigerant (indicated by a white arrow in the figure, hereinafter, an air flow direction). (In this embodiment, in the vertical direction). Further, the heat exchanger 1 is provided between the plurality of heat exchange units 10 arranged in a direction orthogonal to the air flow direction and outside the heat exchange units 10 located on both outer sides, as described later. It has a plurality of heat transfer fins 100 fixed in contact with the outer surface of the tube.

As shown in FIGS. 2 and 3, the plurality of heat exchange units 10 each include a plurality of flat tubes 20 through which a refrigerant flows, and a pair of headers 30 connected to both ends of the plurality of flat tubes 20. Have.

The plurality of flat tubes 20 are formed of flat tube members, and the interior is partitioned into a plurality of spaces in the longitudinal direction of the cross section by inner fins (not shown). Each of the plurality of flat tubes 20 extends in a direction orthogonal to the air flow direction, and a longitudinal direction of the cross section is directed to the air flow direction. In addition, the plurality of flat tubes 20 are respectively arranged in the air flow direction. In the present embodiment, as shown in FIG. 2, four flat tubes 20 are connected to a pair of headers 30.

Each of the pair of headers 30 is formed of a cylindrical member having both ends closed, and has a central axis directed in the air flow direction. The ends of the plurality of flat tubes 20 are connected to the pair of headers 30 along the respective central axes.

The plurality of heat exchange units 10 allow the headers 30 of the adjacent heat exchange units 10 to communicate with each other and partition the inside of the header 30 in the direction of the central axis, thereby forming a refrigerant flow path in the heat exchanger 1.

Here, the pair of headers 30 are, as shown in FIGS. 5 and 6, respectively, a cylindrical member 31, a pair of closing members 32 for closing both ends of the cylindrical member 31, and the inside of the cylindrical member 31. And a plurality of partition members 33 for partitioning in the axial direction.

The tubular member 31 is provided as a long hole extending in the central axis direction, and is provided as a plurality of tube connection holes 31 a for connecting the ends of the flat tubes 20 and the long hole extending in the circumferential direction. And a plurality of header communication holes 31c formed in a circular shape and communicating the headers 30 of the adjacent heat exchange units 10 with each other. Have been.

The closing member 32 is formed of a columnar member, and closes both ends of the tubular member 31 while being inserted into both ends of the tubular member 31.

The partition member 33 has a half in the circumferential direction having the same outer diameter as the outer diameter of the cylindrical member 31, and the other half in the circumferential direction has the same outer diameter as the inner diameter of the cylindrical member 31. It is formed in dimensions. The partition member 33 partitions the inside of the tubular member 31 in the axial direction by inserting a portion having a small outer diameter into the partition member insertion hole 31b of the tubular member 31.

ヘッダ Further, the headers 30 of the heat exchange units 10 adjacent to each other are communicated via the header communication member 34. The header communication member 34 has a plate-shaped portion 34a formed in a rectangular shape, and a pair of tubular portions 34b arranged in the longitudinal direction of the plate-shaped portion 34a and penetrating the plate-shaped portion 34a. The header communication member 34 is inserted into the header communication hole 31c of the tubular member 31 with both ends of the pair of tubular portions 34b being sandwiched between the tubular members 31 adjacent to each other. Is done.

熱 The heat transfer fins 100 are corrugated fins obtained by bending a metal plate into a corrugated shape. As shown in FIG. 3, the heat transfer fin 100 has a tube contact portion 101 in which the apex portion of the waveform is formed in a planar shape, and a middle portion located between the tube contact portion 101 and the flat surface of the flat tube 20. Unit 102. The tube contact portion 101 is provided with a heat transfer promoting portion 103 for changing the flow of air flowing through the gap between the heat transfer fins 100 to promote the transfer of heat to the air.

熱 The heat transfer promoting portion 103 has a rectangular projecting piece 103a formed by cutting and raising the tube contact portion 101. The tip of the protruding piece 103a is directed upstream in the air flow direction in a space surrounded by the flat tube 20, the tube contact portion 101 of the heat transfer fin 100, and the intermediate portion 102.

The heat exchanger 1 integrates all members of the plurality of flat tubes 20, the plurality of headers 30 (the tubular member 31, the closing member 32, the partition member 33), the plurality of header communication members 34, and the plurality of heat transfer fins 100. In this state, they are fixed to each other by brazing.

In the heat exchanger 1 configured as described above, as shown by a solid arrow in FIG. 1, the refrigerant is a downstream end of one header 30 of the heat exchange unit 10 located at the lowermost side in the air flow direction. And flows out from the end on the upstream side in the air flow direction of one header 30 of the heat exchange unit 10 located at the lowermost side.

Specifically, the refrigerant flowing from the downstream side of one of the headers 30 of the lowermost heat exchange unit 10 in the air circulation direction sequentially passes through the flat tubes 20 located at the most downstream side in the air circulation direction of each heat exchange unit 10. It circulates upward. In addition, the refrigerant that has flowed to the most downstream side in the air circulation direction of one header 30 of the uppermost heat exchange unit 10 sequentially passes through the second flat tubes 20 from the most downstream side in the air circulation direction of each heat exchange unit 10 to the lower side. Distribute toward. The refrigerant flowing into one header 30 of the lowermost heat exchange unit 10 flows upward through the third flat tubes 20 from the most downstream side in the air flow direction of each heat exchange unit 10 in order. The refrigerant flowing into one header 30 of the uppermost heat exchange unit 10 flows through the flat tubes 20 on the most upstream side in the air flow direction of each heat exchange unit 10 sequentially downward, and flows out of the heat exchanger 1. I do.

At this time, the refrigerant that has flowed through the flat tube 20 from one header 30 toward the other header 30 flows from the other header 30 when flowing through the flat tube 20 of the heat exchange unit 10 adjacent to the upper side or the lower side. The flat tube flows toward one header 30. As described above, the refrigerant flowing vertically in the heat exchanger 1 flows meandering between the pair of headers 30.

As shown in FIG. 7, when the air that exchanges heat with the refrigerant flows through the gap between the heat transfer fins 100, the air that flows along the tube contact portion 101 comes into contact with the protruding piece 103a, and Will be disturbed in the vicinity of. Thereby, the air flowing along the flat tube 20 is disturbed in flow, so that heat transfer to the flat tube 20 and the heat transfer fins 100 is promoted, and the heat exchange between the refrigerant flowing in the flat tube 20 and the air is performed. The amount increases.

As described above, according to the heat exchanger of the present embodiment, the heat transfer fin 100 has the tube contact portion 101 that comes into surface contact with the flat surface of the flat tube 20, and the tube contact portion 101 is provided with an air flow. A heat transfer promoting section 103 for promoting the transfer of heat to the air by changing the temperature is formed.

Thereby, by changing the flow of the air flowing near the flat tube 20, the transfer of heat to the air can be promoted. Therefore, the heat exchange amount can be reduced without increasing the heat transfer area of the heat transfer fins 100. It is possible to increase.

熱 The heat transfer promoting portion 103 is formed by cutting and raising a part of the tube contact portion 101.

This makes it possible to form the heat transfer promoting portion 103 without attaching another component, and to reduce the number of components.

先端 In the heat transfer promoting section 103, the tip of the protruding piece 103a is directed in the direction opposite to the direction of air flow.

This disturbs the flow of the air in contact with the protruding piece 103a, whereby the air is agitated and the transfer of heat between the air and the flat tube 20 can be promoted.

Further, a pair of headers 30 are provided so as to extend in the air circulation direction, and the plurality of heat exchange units 10 are arranged in directions perpendicular to each other in the air circulation direction.

Thereby, the flat tube 20 having a large width dimension can be connected to the header 30 without increasing the radial dimension of the header 30, so that the ratio of the header 30 in the air flow path is minimized. The required heat exchange ability can be exhibited even when the installation space is limited.

FIGS. 8 and 9 show another embodiment of the present invention.

As shown in FIGS. 8 and 9, the heat transfer promoting portion 103 of this embodiment has a triangular projecting piece 103 b formed by cutting and raising the tube contact portion 101 and the intermediate portion 102 of the heat transfer fin 100. doing. The tip of the protruding piece 103b is directed in the air flow direction in a space surrounded by the flat tube 20, the tube contact portion 101 of the heat transfer fin 100, and the pair of intermediate portions 102. The projecting piece 103b is inclined upward in the air flow direction in a space surrounded by the flat tube 20, the tube contact portion 101 and the intermediate portion 102 of the heat transfer fin 100, and the tube contact portion 101 and the intermediate portion Each of the surfaces 102 is inclined upward from one side in the width direction to the other side. In addition, the protruding piece 103 b protruding into the space surrounded by the flat tube 20, the tube contact portion 101 of the heat transfer fin 100, and the pair of intermediate portions 102 is located on one side in the width direction of the tube contact portion 101 and the tube contact portion 101. The intermediate portion 102 and the intermediate portion 102 located on the other side are provided at positions different from each other in the air flow direction.

In the heat exchanger configured as described above, the air that exchanges heat with the refrigerant, when flowing through the gap between the heat transfer fins 100, as shown in FIG. By contacting the protruding piece 103b located on one side in the width direction of the tube contact portion 101 and the protruding piece 103b located on the other side in the width direction in this order, the fluid flows in a spiral. Thereby, the air flowing through the gap between the heat transfer fins 100 is swirled, thereby promoting heat transfer to the flat tube 20 and the heat transfer fins 100, and the refrigerant flowing through the flat tube 20 communicates with the refrigerant. The amount of heat exchange with air increases.

As described above, according to the heat exchanger of the present embodiment, similarly to the above-described embodiment, by changing the flow of the air flowing near the flat tube 20, the transfer of heat to the air can be promoted. Therefore, it is possible to increase the amount of exchanged heat without increasing the heat transfer area of the heat transfer fins 100.

熱 In the heat transfer promoting section 103, the tip of the protruding piece 103b is directed in the direction of air flow.

Thereby, the air flowing through the gap between the heat transfer fins 100 can be guided in a predetermined direction by flowing along the protruding pieces 103b, and the air can efficiently contact the heat transfer fins 100. As a result, heat transfer can be promoted.

(4) The heat transfer promoting portion 103 is formed in the middle portion 102 between the top portions, together with the top portion having a corrugated shape.

This allows more air flowing through the gap between the heat transfer fins 100 to be guided in the target direction, and allows the air to contact the heat transfer fins 100 more efficiently.

In the above embodiment, the heat exchanger of the present invention is applied to an air conditioner for a vehicle. However, the present invention is not limited to this. For example, the present invention can be applied to an air conditioner for a room in a building, a heat exchanger used for a freezer showcase, a refrigerated showcase, and the like.

In the above embodiment, the present invention is applied to the heat exchanger that exchanges heat between the refrigerant and the air. However, the present invention is not limited to this. For example, the present invention may be applied to a heat exchanger that exchanges heat between water or antifreeze and air.

Further, in the above-described embodiment, the heat transfer promoting portion 103 is formed by cutting and raising the heat transfer fin 100 to form the projecting

pieces

103a and 103b. However, the present invention is not limited to this. As long as it changes the flow of air flowing in the vicinity of the flat tube 20 or along the heat transfer fins 100, for example, a projection provided integrally with the heat transfer fins or a depression provided on the surface of the heat transfer fins May be used as the heat transfer promoting section.

DESCRIPTION OF SYMBOLS 1 ... Heat exchanger, 10 ... Heat exchange unit, 20 ... Flat tube, 30 ... Header, 100 ... Heat transfer fin, 101 ... Tube contact part, 102 ... Middle part, 103 ... Heat transfer promotion part, 103a, 103b ... Projection Pieces.

Claims

A flat tube through which the first fluid flows, and a heat transfer fin provided on an outer surface of the flat tube and formed by bending a plate-like member, the first fluid flowing through the flat tube and the outside of the flat tube A heat exchanger for exchanging heat with a second fluid flowing through the heat exchanger,
The heat transfer fin has a tube contact portion that makes surface contact with the flat surface of the flat tube,
A heat exchanger, wherein a heat transfer promoting portion is formed in the tube contact portion to change the flow of the second fluid to promote the transfer of heat to the second fluid.
The heat exchanger according to claim 1, wherein the heat transfer promoting portion is formed by cutting and raising a part of the tube contact portion.
3. The heat exchanger according to claim 2, wherein a tip of the cut and raised portion of the heat transfer promoting unit is directed in a direction opposite to a flow direction of the second fluid. 4.
3. The heat exchanger according to claim 2, wherein a tip of the cut and raised portion of the heat transfer promoting unit is directed in a flow direction of the second fluid. 4.
The tube contact portion is disposed on the top of the heat transfer fin formed in a corrugated shape,
The heat exchanger according to any one of claims 1 to 4, wherein the heat transfer promoting portion is formed at an intermediate portion between the top portions, together with the top portion having a corrugated shape.
Flat tubes, a pair of headers connected to both ends of the flat tube, comprising a plurality of heat exchange units,
The flat tube is provided such that the longitudinal direction of the cross section is oriented in the flow direction of the second fluid,
The pair of headers are provided such that their longitudinal directions extend in the flow direction of the second fluid,
The heat exchanger according to any one of claims 1 to 5, wherein the plurality of headers are arranged in a direction orthogonal to a flow direction of the second fluid.