EP2447656B1

Movatterモバイル変換

Info

Publication number: EP2447656B1
Application number: EP11185348.7A
Authority: EP
Inventors: Dong Ho Park; Hayase Gaku; Kang Tae Seo; Young Min Kim
Original assignee: Samsung Electronics Co Ltd
Current assignee: Samsung Electronics Co Ltd
Priority date: 2010-10-28
Filing date: 2011-10-17
Publication date: 2016-12-21
Anticipated expiration: 2031-10-17
Also published as: KR20120044850A; EP2447656A2; CN102455089A; CN102455089B; US20120103587A1; EP2447656A3

Description

BACKGROUND

1. Field

Embodiments of the present disclosure relate to a heat exchanger with an improved heat exchange structure.

2. Description of the Related Art

A heat exchanger is mounted in devices operating based upon a refrigeration cycle, such as air conditioners or refrigerators. The heat exchanger includes a plurality of heat exchanger fins and a refrigerant pipe extending through the heat exchanger fins to guide a refrigerant. Contact area between the heat exchanger fins and external air introduced to the heat exchanger is increased to improve heat exchange efficiency between the refrigerant flowing in the refrigerant pipe and the external air.
When the contact area between the heat exchanger fins and external air contacting the heat exchanger fins is large or when resistance applied to air contacting the heat exchanger fins is small, heat exchange efficiency is increased. However, if the contact area between the heat exchanger fins and air is too large, large resistance is applied to air passing through the heat exchanger fins. On the other hand, if the contact area is reduced to lower resistance applied to air, heat exchange efficiency is lowered. For this reason, it may be necessary to provide fins having an optimal shape based on the heat exchanger employed.
For a heat exchanger used as an evaporator (that is, the refrigeration cycle performs a heating operation), if outdoor temperature is too low, the surface temperature of the heat exchanger is lowered to below zero Celsius, and moisture contained in outdoor air is attached to the surface of the cold heat exchanger in a frozen state, thereby reducing heat exchange efficiency of the heat exchanger.
US 4,705,105 A discloses a heat exchanger with the features of the pre-characterizing part ofclaim 1. It discloses a room air conditioner with a nest of tubes and numerous thin metallic fins attached thereto. Further used are an evaporator and a condenser wherein it is said that thermally conducting tubes of the evaporator and condenser are air cooled by a corresponding flow of air passing the tubes and associated fins. Such a fin may comprise a plate and a protrusion protruding from the plate. Each protrusion is provided with a louver unit to perform heat exchange with the air passing therethrough.
US 4,676,304 A discloses a heat exchanger with a flat metal tube and a plurality of corrugated fin units disposed therebetween. There seems to be no coupling of corresponding heat exchanger fins or fin units to an outer circumference of the refrigerant pipe. Fin units comprise a plurality of plate portions, each comprising inclined louvers and parallel lovers.
US 2002/003035 A1 discloses slits provided on both surfaces of corresponding air guide fins. However, there is no protrusion and there are no slits disposed on opposite sides of the protrusion, namely the left and right sides of such protrusion.
US 2001/004012 A1 discloses a fin and tube type heat-exchanger with a number of slit groups in each of which slits are arranged in a number of rows and are formed on each stage, namely upper stage and lower stage of each cooling fin.
US 2005/077036 A1 discloses fins for heat exchanger only with a plurality of louvers without any slits and without any protrusion.

SUMMARY

It is an object of the present disclosure to provide a heat exchanger having a structure to effectively achieve heat exchange between air and heat exchanger fins and to restrain frost formation on the surfaces of heat exchanger fins.
Additional aspects of the disclosure will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of the disclosure.
The object is solved by the features according to the independent claim.
Advantageous embodiments are disclosed by the subclaims.
The louver unit may include first cutouts provided at the protrusion and a plurality of guide plates provided in parallel to each other so that the guide plates are spaced apart from each other by the respective first cutouts, the first cutouts and the guide plates being alternately arranged.
Each of the guide plates may have a width of 0.5 mm to 3 mm.
The protrusion may include first inclined surfaces inclined relative to the plate, the guide plates may be provided at the first inclined surfaces, and the angle between the guide plates and the first inclined surfaces may be 10 to 60 degrees.
Each of the slits includes second inclined surfaces inclined relative to the plate, a top surface formed between the second inclined surfaces, and a second cutout provided at the rear of the top surface.
The top surface may have a width of 0.5 mm to 5 mm.
The first inclined surfaces may be disposed at the plate in a symmetrical fashion, the distance between a line formed at the position where the first inclined surfaces join each other and the plate may constitute a height of the protrusion, and the protrusion may have a height of 0.5 mm to 4 mm.
The first inclined surfaces may be disposed at the plate in a symmetrical fashion, the distance between a flat surface connected between the first inclined surfaces and the plate may constitute a height of the protrusion, and the protrusion may have a height of 0.5 mm to 4 mm.
The heat exchanger fin may include a plurality of plates stacked at an interval.
The protrusion may include first inclined surfaces disposed in a symmetrical fashion to form a 'V' shape, and the guide plates and the first cutouts may be provided at the first inclined surfaces.
The angle between the first inclined surfaces and the guide plates provided at the first inclined surfaces may be 10 to 60 degrees.
The protrusion may include first inclined surfaces disposed in a symmetrical fashion and a flat surface connected between the first inclined surfaces, the guide plates and the first cutouts being provided at the first inclined surfaces or the flat surface.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects of the disclosure will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is a perspective view illustrating a heat exchanger according to an embodiment of the present disclosure;
FIG. 2 is a perspective view illustrating part of a heat exchanger fin ofFIG. 1;
FIG. 3 is a front view ofFIG. 2;
FIG. 4 is a sectional view taken along line I-I ofFIG. 3;
FIG. 5 is an enlarged sectional view illustrating part ofFIG. 4;
FIG. 6 is a view illustrating air flow around the heat exchanger fin ofFIG. 3;
FIG. 7 is a sectional view taken along line II-II ofFIG. 6;
FIG. 8 is a table illustrating heat exchange efficiency of the heat exchanger fin ofFIG. 3;
FIG. 9 is a front view illustrating a conventional fin;
FIG. 10 is a sectional view taken along line A-A ofFIG. 9;
FIG. 11 is a front view illustrating a heat exchanger according to another embodiment of the present disclosure;
FIG. 12 is a front view illustrating a heat exchanger according to another embodiment of the present disclosure;
FIG. 13 is a sectional view taken along line III-III ofFIG. 12;
FIG. 14 is a front view illustrating a heat exchanger according to another embodiment of the present disclosure;
FIG. 15 is a sectional view taken along line IV-IV ofFIG. 14;
FIG. 16 is a front view illustrating a heat exchanger not forming part of the present invention,
FIG. 17 is a sectional view taken along line V-V ofFIG. 16;
FIG. 18 is a front view illustrating a heat exchanger according to yet another embodiment of the present disclosure; and
FIG. 19 is a sectional view taken along line VI-VI ofFIG. 18.

DETAILED DESCRIPTION

Reference will now be made in detail to the embodiments of the present disclosure, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout.
FIG. 1 is a perspective view illustrating a heat exchanger according to an embodiment of the present disclosure.
As shown inFIG. 1, aheat exchanger 10 includes arefrigerant pipe 20, in which a refrigerant flows, andheat exchanger fins 30 coupled to the outer circumference of therefrigerant pipe 20.
Therefrigerant pipe 20 is configured in the shape of a hollow tube in which the refrigerant flows. Therefrigerant pipe 20 is lengthened to increase heat exchange area between the refrigerant flowing in therefrigerant pipe 20 and external air. However, it may be difficult to extend therefrigerant pipe 20 in one direction due to spatial restrictions. Consequently, therefrigerant pipe 20 is repeatedly bent at opposite ends of theheat exchanger 10 in opposite directions to efficiently increase heat exchange area per unit volume.
The refrigerant flowing in therefrigerant pipe 20 is formed by mixing different Freon products exhibiting different properties. For example, R-134a and R410A may be used.
The refrigerant may be phase changed (compressed) from a gas state to a liquid state to perform heat exchange with external air. On the other hand, the refrigerant may be phase changed (expanded) from a liquid state to a gas state to perform heat exchange with external air. When the refrigerant is phase changed from a gas state to a liquid state, theheat exchanger 10 is used as a condenser. When the refrigerant is phase changed from a liquid state to a gas state, theheat exchanger 10 is used as an evaporator.
The refrigerant, flowing in therefrigerant pipe 20, is compressed or expanded to discharge heat to the surroundings or to absorb heat from the surroundings. Theheat exchanger fins 30 are coupled to therefrigerant pipe 20 so that the refrigerant efficiently discharges or absorbs heat during compression or expansion.
Theheat exchanger fins 30 are disposed at a predetermined interval in the direction in which therefrigerant pipe 20 extends.
Theheat exchanger fins 30 may be made of various metal materials, such as aluminum, exhibiting high thermal conductivity. Theheat exchanger fins 30 are coupled to the outer circumference of therefrigerant pipe 20 in a contact state to increase contact area between therefrigerant pipe 20 and external air.
The interval between theheat exchanger fins 30 may be reduced to increase the number of theheat exchanger fins 30. If the interval between theheat exchanger fins 30 is too small, however, theheat exchanger fins 30 may act as resistance to air F introduced to theheat exchanger 10, as shown inFIG. 1, resulting in pressure loss. For this reason, the interval between theheat exchanger fins 30 may be properly adjusted.
FIG. 2 is a perspective view illustrating part of one of the heat exchanger fins ofFIG. 1,FIG. 3 is a front view ofFIG. 2,FIG. 4 is a sectional view taken along line I-I ofFIG. 3, andFIG. 5 is an enlarged sectional view illustrating part ofFIG. 4.
As shown inFIGS. 2 to 5, theheat exchanger fin 30 includes aplate 40, aprotrusion 70 protruding from theplate 40, slits 50 provided at opposite sides of theprotrusion 70, and alouver unit 60 provided at theprotrusion 70.
Theplate 40 is made of an aluminum alloy. Theplate 40 is thin. Theplate 40 includes location holes 32, through which therefrigerant pipe 20 extends in a contact state.
Each of the location holes 32 contacts the outer circumference of therefrigerant pipe 20 to support therefrigerant pipe 20. Each of the location holes 32 is formed in a shape corresponding to the outer circumference of therefrigerant pipe 20 to surround therefrigerant pipe 20.
As shown inFIG. 2, each of the location holes 32 protrudes frontward and rearward from theplate 40 to stably support therefrigerant pipe 20 and to increase contact area between therefrigerant pipe 20 and theheat exchanger fin 30 so that heat exchange is smoothly achieved.
Theprotrusion 70 protrudes frontward from theplate 40.
Theprotrusion 70 includes firstinclined surfaces 72 disposed at a predetermined angle relative to theplate 40. The firstinclined surfaces 72 are disposed on theplate 40 in a symmetrical fashion to form a 'V' shape.
The firstinclined surfaces 72 guide air, passing through theslits 50, to thelouver unit 60. That is, air, accelerated while passing through theslits 50, naturally flows along the firstinclined surfaces 72 so that speed of the air is not reduced. The air flowing along the firstinclined surfaces 72 contacts thelouver unit 60 to perform heat exchange with the refrigerant flowing in therefrigerant pipe 20, thereby increasing heat transfer efficiency.
As previously described, the firstinclined surfaces 72 are disposed on theplate 40 in a symmetrical fashion to form a 'V' shape. Acontact line 74 is formed vertically at a position where the firstinclined surfaces 72 join each other. The distance between thecontact line 74 and theplate 40 constitutes a height H of theprotrusion 70.
If the height H of theprotrusion 70 is increased, the area of the firstinclined surfaces 72 increases, thereby increasing the contact area between the firstinclined surfaces 72 and external air. If the height H of theprotrusion 70 is excessively increased, however, the firstinclined surfaces 72 act as resistance to external air. As a result, the speed of air is reduced and pressure of the air is reduced (pressure loss), thereby reducing heat transfer efficiency. The height H of theprotrusion 70 is 0.5 mm to 4.0 mm.
Meanwhile, the firstinclined surfaces 72 may be disposed on the plate in a non-symmetrical fashion, which will be described in detail below in connection with aheat exchanger fin 300 according to another embodiment of the present disclosure.
Theslits 50 are disposed at opposite sides of theprotrusion 70.
Theslits 50 prevent moisture contained in external air from being attached to the surface of theheat exchanger fin 30. Also, the slits accelerate external air introduced to theheat exchanger 10 and guide the external air to theprotrusion 70 and thelouver unit 60. Each of theslits 50 includes secondinclined surfaces 52 inclined relative to theplate 40, atop surface 54 provided between the secondinclined surfaces 52, and asecond cutout 56 provided at the rear of thetop surface 54.
The secondinclined surfaces 52 protrude from theplate 40 so that the secondinclined surfaces 52 are disposed at a predetermined angle relative to theplate 40 to define a space, in which external air flows, between theplate 40 and thetop surface 54.
Thetop surface 54 is formed in an approximately trapezoidal shape. Thetop surface 54 is disposed between the second inclined surfaces 52. Air, passing through each of theslits 50, is divided by thetop surface 54 and flows along the front and rear of thetop surface 54, resulting in turbulent flow. As a result, the air is further accelerated.
Thetop surface 54 may be formed in other shapes. For example, thetop surface 54 may be formed in the shape of a triangle, a semicircle, an arc or a quadrangle. Even if thetop surface 54 is formed in any one of the above-specified shapes, the same effect in that air, passing through each of theslits 50, is divided by thetop surface 54 is achieved.
Anedge 58 is formed betweentop surface 54 and each of the second inclined surfaces 52. Theedge 58 prevents frost formation. Frost formation is a phenomenon in which moisture contained in external air is attached to the surface of theheat exchanger fin 30 in a frozen state. Frost is formed at a flat surface on which more than a predetermined amount of moisture is easily collected. More than a predetermined amount of moisture is prevented from being collected by the provision of theedge 58, thereby preventing or retarding frost formation.
Thesecond cutout 56 is provided at the rear of thetop surface 54 to guide external air, introduced to theheat exchanger 10, to thelouver unit 60 and to minimize resistance applied to the air flowing along thetop surface 54.
When theheat exchanger 10 is used as an evaporator to heat a room, the refrigerant, flowing in therefrigerant pipe 20, is expanded from a liquid state to a gas state to absorb heat from the surroundings. As a result, the surface temperature of therefrigerant pipe 20 is generally lowered to below zero degrees Celsius. Thesecond cutout 56 retards heat exchange between therefrigerant pipe 20 and thecorresponding slit 50, thereby preventing frost formation.
The width D of thetop surface 54 may be 0.5 to 5.0 mm in consideration of resistance applied to air passing through thecorresponding slit 50.
Theslits 50 are disposed at opposite sides of theprotrusion 70. At least twoslits 50 may be disposed in the vertical direction of theplate 40 so that theslits 50 are spaced apart from each other.
When the slits are disposed in the vertical direction of theplate 40 so that theslits 50 are spaced apart from each other, the strength of theslits 50 and theplate 40 is higher than when the slits are disposed without separation.
Thelouver unit 60 is provided at theprotrusion 70.
Thelouver unit 60 includesguide plates 62 provided at the firstinclined surfaces 72 andfirst cutout 64 alternating with theguide plates 62.
Theguide plates 62 are disposed at a predetermined angle relative to the first inclined surfaces 72. Theguide plates 62 are arranged in parallel to each other so that theguide plates 62 are spaced apart from each other.
External air, accelerated after having passed through theslits 50, flows along the firstinclined surfaces 72 and contacts theguide plates 62 to perform heat exchange with theguide plates 62. Theguide plates 62 increase contact area between theheat exchanger fin 30 and external air to increase heat exchange efficiency.
When the pitch (width) P of each of theguide plates 62 is small or when the inclination angle α between each of theguide plates 62 and the firstinclined angle 72 is small, contact area between theheat exchanger fin 30 and external air increases. If the pitch P is too small or the inclination angle α is too large, however, speed of air passing through thelouver unit 60 is reduced by theguide plates 62, resulting in pressure loss. As a result, overall heat exchange efficiency is lowered. Consequently, the pitch P and the inclination angle α are properly adjusted. For example, the pitch P may be 0.5 mm to 3.0 mm and the inclination angle α may be 10 degrees to 60 degrees.
Also, the edge of each of theguide plates 62 prevents or retards frost formation, as previously described.
Thefirst cutouts 64 are provided at the firstinclined surfaces 72 so that thefirst cutouts 64 and theguide plates 62 are alternately disposed. Thefirst cutouts 64 guide external air, accelerated after having passed through theslits 50, to flow along one side of each of theguide plates 62, thereby effectively achieving heat transfer between theguide plates 62 and external air.
FIG. 6 is a view illustrating air flow around the heat exchanger fin ofFIG. 3, andFIG. 7 is a sectional view taken along line II-II ofFIG. 6.
FIGS. 6 and7 illustrate calculation results of air flow around theheat exchanger fin 30 using computational fluid dynamics (CFD). In the drawings, lines indicate air flow direction, and lengths of the lines indicate air speed. Longer lengths of the lines represent higher air speed.
As shown inFIGS. 6 and7, air passing through theslits 50 of theheat exchanger fin 30 moves faster than air not passing through theslits 50 since the air introduced into theslits 50 is accelerated by thetop surface 54 of each of theslits 50.
The air, accelerated by theslits 50, flows to thelouver unit 60 without reduction of air speed. As previously described, theslits 50 accelerate air introduced into theslits 50 and guide the introduced air to thelouver unit 60.
The air flows on the surfaces of theguide plates 62 and between theguide plates 62, i.e. at thefirst cutouts 64, at high speed to perform heat exchange with theguide plates 62.
FIG. 8 is a table illustrating heat exchange efficiency of the heat exchanger fin ofFIG. 3.FIGS. 9 and10 are a front view and a sectional view illustrating a conventional fin compared with the heat exchange efficiency of the heat exchanger fin ofFIG. 3.
As shown inFIGS. 9 and10, aconventional fin 1 is provided at the middle thereof withsilts 5 but does not include aprotrusion 70 and alouver unit 60, which are included in theheat exchanger fin 30 ofFIG. 3.
In the table ofFIG. 8, wind speed indicates speed of external air introduced to the fin, and fin pitch indicates the distance between the respective fins. Smaller pitch means that a larger number of fins may be disposed in a limited space.
As the result of a comparison of heat transfer efficiency between the conventional fins and the inventive fins having the same pitch (1.5 mm), the inventive fins have approximately 7.4 % to 8.2 % higher heat transfer efficiency in all wind speed sections than the conventional fins.
Also, even when the pitch of the inventive fins is increased from 1.5 mm to 1.7 mm, the inventive fins have higher heat transfer efficiency than the conventional fins having a pitch of 1.5 mm. This means that higher heat transfer efficiency is achieved using a smaller number of inventive fins, thereby reducing material costs.
FIGS. 11 to 19 are front views and sectional views illustratingheat exchanger fins 200, 300, 400, 500 and 600 according to other embodiments of the present disclosure.
FIG. 11 illustrates aheat exchanger fin 200 according to another embodiment of the present disclosure. Aslit 250, protruding frontward from theheat exchanger fin 200, is formed as a single body.
FIGS. 12 and13 illustrate aheat exchanger fin 300 according to another embodiment of the present disclosure. Aprotrusion 370 of theheat exchanger fin 300 is formed in a non-symmetrical shape. That is, firstinclined surfaces 372a and 372b constituting theprotrusion 370 are formed in a non-symmetrical 'V' shape.
An inclination angle β between the firstinclined surface 372a and the front of aplate 40 is larger than an inclination angle β' between the firstinclined surface 372b and the front of theplate 40. Consequently, the area of the firstinclined surface 372a is smaller than that of the firstinclined surface 372b. Also, acontact line 374 at which the firstinclined surfaces 372a and 372b join each other deviates from the middle of theplate 40.
FIGS. 14 and15 illustrate aheat exchanger fin 400 according to another embodiment of the present disclosure.Guide plates 462 provided at alouver unit 60 of theheat exchanger fin 400 have different inclination angles.
That is, theguide plates 462 may be provided at firstinclined surfaces 72 so that theguide plates 462 are at different inclination angles relative to the first inclined surfaces 72.
FIGS. 16 and17 illustrate aheat exchanger fin 500 which does not form part of the present invention.Slits 50, protruding frontward from theheat exchanger fin 500, are provided at only one side of a protrusion 700.
In this case, theslits 50 are disposed at an external air introduction side.
FIGS. 18 and19 illustrate aheat exchanger fin 600 according to yet another embodiment of the present disclosure. Aprotrusion 670 of theheat exchanger fin 600 includes aflat surface 676.
Theflat surface 676 is provided between firstinclined surfaces 672. The firstinclined surfaces 672 may be symmetric with respect to theflat surface 676. The distance between theflat surface 676 and aplate 40 constitutes the height of theprotrusion 670. The height of theprotrusion 670 is 0.5 mm to 4.0 mm.
Guide plates 62 may be selectively provided at the firstinclined surfaces 672 or theflat surface 676. Alternatively, theguide plates 62 may be provided at both the firstinclined surfaces 672 and theflat surface 676.
At least two of the previous embodiments may be combined. For example, when the embodiment ofFIGS. 12 and13 and the embodiment ofFIGS. 14 and15 are combined, theguide plates 462 may be provided at the firstinclined surfaces 372a and 372b of theprotrusion 370 formed in a non-symmetrical shape (characteristic of the embodiment of FIG.FIGS. 12 and13) so that theguide plates 462 are at different inclination angles to the firstinclined surfaces 372a and 372b (characteristic of the embodiment ofFIGS. 14 and15).
As is apparent from the above description, heat exchange between air and the heat exchanger fins of the embodiments of the present disclosure is effectively achieved, thereby improving heat exchange efficiency.
Also, frost formation is restrained on the surfaces of the heat exchanger fins, thereby improving heat exchange efficiency.
Although a few embodiments of the present disclosure have been shown and described, it would be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles of the invention, the scope of which is defined in the claims.

Claims

A heat exchanger (10) comprising:
a refrigerant pipe (20) in which a refrigerant flows; and
a heat exchanger fin (30, 200, 300, 400, 600) coupled to an outer circumference of the refrigerant pipe (20), wherein the heat exchanger fin comprises:
a plate (40);
a protrusion (70, 370, 670) protruding from the plate (40);a louver unit (60) provided at the protrusion to perform heat exchange;
characterized by
slits (50) disposed at right and left sides of the protrusion (70, 370, 670) to guide air to the protrusion, wherein said louver unit (60) is adapted to perform said heat exchange with the air having passed through the slits (50), and
wherein air flows in the slits disposed at the right side of the protrusion, and then passes through the protrusion, and finally flows out of the slits disposed at the left side of the protrusion.
The heat exchanger according to claim 1, wherein the louver unit (60) comprises:
first cutouts (64) provided at the protrusion (70); and
a plurality of guide plates (62, 462) provided in parallel to each other so that the guide plates are spaced apart from each other by the respective first cutouts (64),
the first cutouts (64) and the guide plates (62, 462) being alternately arranged.
The heat exchanger according to claim 2, wherein each of the guide plates (62) has a width of 0.5 mm to 3 mm.
The heat exchanger according to claim 2, wherein
the protrusion (70, 470) comprises first inclined surfaces (72, 672, 372 a, b) inclined relative to the plate (40),
the guide plates (62, 462) are provided at the first inclined surfaces, and
an angle between the guide plates and the first inclined surfaces is 10 to 60 degrees.
The heat exchanger according to claim 1, wherein each of the slits (50) comprises:
second inclined surfaces(52) inclined relative to the plate (40);
a top surface (54) formed between the second inclined surfaces (52); and
a second cutout (56) provided at a rear of the top surface (54).
The heat exchanger according to claim 5, wherein the top surface (54) has a width of 0.5 mm to 5 mm.
The heat exchanger according to claim 4, wherein
the first inclined surfaces (52) are disposed at the plate (40) in a symmetrical fashion, a distance between a line formed at a position where the first inclined surfaces join each other and the plate constitutes a height (H) of the protrusion (70, 470), and
the protrusion has a height of 0.5 mm to 4 mm.
The heat exchanger according to claim 4, wherein
the first inclined surfaces (52) are disposed at the plate (40) in a symmetrical fashion, a distance between a flat surface (676) connected between the first inclined surfaces (52) and the plate (40) constitutes a height (H) of the protrusion, and
the protrusion has a height of 0.5 mm to 4 mm.
The heat exchanger according to claim 1, wherein the heat exchanger fin (30, 200, 300, 400, 600) comprises a plurality of plates (40) stacked at an interval.