JP2008209025A - Heat transfer member and heat exchanger using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat transfer member capable of suppressing clogging of louvers even when the louver pitch is made minute and improving heat transferring efficiency per louver, and to provide a heat exchanger using the same. <P>SOLUTION: The louver 23 equipped with a plane part 21 substantially parallel to a cooling air circulation direction X1 and turned at a predetermined angle θ<SB>0</SB>with respect to the plane part 21 is provided in a plurality of numbers along the cooling air circulation direction X1. Adjacent louvers 23 are disposed offset from each other in a fin thickness direction X2, and the plurality of louvers 23 are shifted in the same direction as seen from the cooling air circulation direction X1 so that a distance LD between the adjacent louvers 23 become large. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a heat transfer member and a heat exchanger that improve performance by turbulent air flow, and is suitable for vehicles.

The fin in the conventional heat exchanger has an armor window-like louver, and the heat transfer coefficient of the fin is improved by the tip effect of the louver. In addition, by inclining the louver at a predetermined angle with respect to the plane portion, the cooling air flow is changed to guide the cooling air to the passage between louvers between adjacent louvers, thereby improving the heat transfer coefficient of the fins. (For example, refer to Patent Document 1).
JP 2003-83690 A

  However, the above-described conventional fin further reduces the distance between adjacent louvers (hereinafter referred to as the distance between louvers) when the louver pitch is made finer in order to further improve the heat exchange performance (heat transfer coefficient). There is a problem in that clogging is likely to cause clogging. Further, when the louver distance is reduced, the flow rate of the cooling air passing through the louver passage is reduced, so that there is a problem that the heat transfer coefficient per louver is lowered.

  In view of the above points, the present invention provides a heat transfer member capable of suppressing clogging of a louver and improving the heat transfer coefficient per louver even if the louver pitch is reduced, and a heat exchanger using the heat transfer member The purpose is to provide.

In order to achieve the above object, the present invention is a heat transfer member that is formed from a thin plate member and is placed in a fluid and transfers heat to and from the fluid, and is substantially parallel to the fluid flow direction (X1). The louver (23) twisted at a predetermined angle (θ ₀ ) with respect to the plane portion (21) is provided in the plane portion (21). And the adjacent louvers (23) are offset from each other in the plate thickness direction (X2), and the plurality of louvers (23) are distances between adjacent louvers (23) (LD ) Is larger when viewed from the fluid flow direction (X1).

  In this way, since the distance (LD) between the adjacent louvers (23) can be increased, clogging of the louvers (23) can be suppressed even if the louver pitch (LP) is made finer. Further, since the fluid can be surely guided to the louver passage (5) formed in the adjacent louvers (23), the heat transfer rate per louver can be improved.

  By the way, the upstream end of the fluid flow direction (X1) in each louver (23) (hereinafter referred to as the upstream end) has a high local heat transfer coefficient due to the tip effect. Next, when the fluid flows through the inter-louver passage (5), the temperature boundary layer develops and the local heat transfer coefficient decreases.

  However, when the louver pitch (LP) is made fine, the upstream end of each louver (23) is buried in the temperature boundary layer of the louver (23) upstream of the louver (23) in the fluid flow direction (X1). Therefore, the tip effect cannot be exhibited well.

  On the other hand, the adjacent louvers (23) are offset from each other in the plate thickness direction (X2) so as to be displaced in the same direction when viewed from the fluid flow direction (X1), whereby each louver (23). The upstream end of the can be disposed at a site through which a low-temperature fluid flows. Thereby, since the tip effect can be satisfactorily exhibited in each louver (23), the heat transfer rate of the heat transfer member can be improved.

In the heat transfer member having the above characteristics, when the direction along the predetermined angle (θ ₀ ) is the louver width direction (X4), the louver width in the adjacent louver (23) in the plurality of louvers (23). The angle (θ ₁ ) between the line (Z) connecting the center points (24) of the direction (X4) and the louver width direction (X4) may be larger than a predetermined angle (θ ₀ ).

  In this way, when the louver pitch (LP) of all the louvers (23) is substantially the same, the distance (LD) between the adjacent louvers (23) can be increased, so the louver pitch (LP). Even if the size of the louver is reduced, clogging of the louver (23) can be suppressed and the heat transfer rate per louver can be improved.

In the heat transfer member having the above characteristics, when the direction along the predetermined angle (θ ₀ ) is the louver width direction (X4), the center point of the louver width direction (X4) in the plurality of louvers (23) ( 24) may be arranged on the same straight line (Z), and the straight line (Z) may be inclined with respect to the center line (Y) in the thickness direction (X2).

  In this way, since the distance between the louvers (LD) can be made equal, the fluid flow in each part of the louver (23) can be made equal, and heat exchange can be promoted.

  Further, in the heat transfer member having the above characteristics, of the plurality of louvers (23), the center point (24) of the louver (23) disposed on the most upstream side of the fluid flow and the louver disposed on the most downstream side of the fluid flow. A line segment connecting the center point (24) of (23) may intersect with the center line (Y) in the thickness direction (X2).

  In this way, since the offset amount can be increased, the distance between louvers (LD) can be further increased. Thereby, even if the louver pitch (LP) is made fine, clogging of the louver (23) can be reliably suppressed and the heat transfer rate per louver can be further improved.

  Moreover, in the heat transfer member having the above characteristics, the heat transfer member may be formed in a corrugated shape so as to have a flat portion (21) and a curved portion (22) connecting between adjacent flat portions (21).

  The “wave shape” in the present invention does not mean only a smooth wave shape formed by a curve, but also includes a sharp wave shape formed by a straight line.

  Moreover, in this invention, it is a heat exchanger provided with the several tube (1) through which a heat carrier flows, and the fin (2) joined to the outer surface of a tube (1) and accelerating | stimulating heat exchange of a heat carrier. The fin (2) is a heat transfer member according to any one of claims 1 to 5.

  By using such a heat transfer member for a heat exchanger, the heat exchange capability can be improved.

  In addition, the code | symbol in the bracket | parenthesis of each means described in this column and the claim shows the correspondence with the specific means as described in embodiment mentioned later.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. The corrugated fin according to the present embodiment is used, for example, in a radiator (heat exchanger) that exchanges heat between cooling water that has cooled a vehicle engine and air.

  FIG. 1 is a front view showing a radiator in the first embodiment. As shown in FIG. 1, the radiator includes a tube 1 through which engine cooling water flows, a corrugated corrugated fin 2 joined to the outer surface of the tube 1, and a flow direction of the cooling water in the tube 1 (of the tube 1 It has a header tank 3 provided at an end portion (longitudinal direction) and communicating with each tube 1, and an insert 4 that forms a reinforcing member of a core portion including the tube 1 and the corrugated fins 2. The engine cooling water corresponds to the heat medium of the present invention.

  The tube 1 is made of metal (in this embodiment, an aluminum alloy), and a cooling water passage through which the cooling water flows is formed inside and formed in a flat shape. A large number of tubes 1 are arranged in a stacked manner, and corrugated fins 2 are arranged between the adjacent tubes 1, and cooling air flows between the adjacent tubes 1. The cooling air corresponds to the fluid of the present invention.

  The corrugated fin 2 promotes heat exchange between the cooling air and the cooling water, and is formed by subjecting a thin metal material to a roller forming method. The corrugated fin 2 includes a plane portion 21 having a surface substantially parallel to a flow direction X1 of cooling air flowing between the tubes 1 (hereinafter referred to as an airflow direction X1), and a curved portion 22 connecting between adjacent plane portions 21. And has a wave shape when viewed from the airflow direction X1. A plurality of the flat portions 21 are arranged along the flow direction of the cooling water (longitudinal direction of the tube 1).

  FIG. 2 is a cross-sectional view of the corrugated fin 2 according to the first embodiment when viewed from the tube stacking direction X3. In FIG. 2, a two-dot chain line indicates a center line Y in the plate thickness direction X2 of the corrugated fin 2 (hereinafter referred to as the fin plate thickness direction X2).

As shown in FIG. 2, an armor window-like louver 23 is integrally formed on the flat portion 21 of the corrugated fin 2 by cutting and raising the flat portion 21. The louver 23 is twisted at a predetermined angle θ ₀ (hereinafter referred to as a twist angle θ ₀ ) with respect to the plane portion 21 when viewed from the stacking direction X3 (hereinafter referred to as the tube stacking direction X3) of the tube 1. A plurality of plane portions 21 are provided along the airflow direction X1. A louver passage 5 is formed between adjacent louvers 23.

  In the present embodiment, the plurality of louvers 23 formed on one flat surface portion 21 include an upstream louver group including a plurality of louvers 23 located on the cooling air flow upstream side and a plurality of louvers located on the cooling air flow downstream side. The louvers are divided into two groups including downstream louvers 23. The twisting direction of the louver 23 belonging to the upstream louver group is different from the twisting direction of the louver 23 belonging to the downstream louver group.

  FIG. 3 is an enlarged view of a portion A in FIG. As shown in FIGS. 2 and 3, in this embodiment, the louver pitches LP of all the louvers 23 are equal. The adjacent louvers 23 are offset from each other in the fin plate thickness direction X2. In the present embodiment, the offset amounts of all the louvers 23 are equal.

In addition, the plurality of louvers 23 are displaced in the same direction when viewed from the airflow direction X1 so that the louver distance LD between adjacent louvers 23 is increased. That is, as shown in FIG. 3, when the direction along the twist angle θ ₀ is the louver width direction X4, a line Z connecting the center points 24 in the louver width direction X4 of the adjacent louvers 23 in the plurality of louvers 23. the angle theta ₁ between louver width direction X4 is larger than the angle theta ₀ a predetermined.

  Furthermore, in this embodiment, the center point 24 of the louver width direction X4 in the plurality of louvers 23 having the same twist direction (that belongs to the same louver group) is arranged on the same straight line Z, and this straight line Z is the fin plate. It is inclined with respect to the center line Y in the thickness direction X2.

  Further, in each louver group, a line segment connecting the center point 24 of the louver 23 arranged on the most upstream side of the cooling air flow and the center point 24 of the louver 23 arranged on the most downstream side of the cooling air flow, It intersects with the center line Y in the fin plate thickness direction X2. That is, in each louver group, the center points 24 in the louver width direction X4 of the plurality of louvers 23 are arranged on one side and the other side in the plate thickness direction X4 with respect to the center line Y of the fin plate thickness direction X2 center line. Has been.

  As described above, adjacent louvers 23 are offset from each other in the fin plate thickness direction X2, and the plurality of louvers 23 are shifted in the same direction when viewed from the airflow direction X1 so that the inter-louver distance LD is increased. Thus, the distance between the louvers of each louver 23 can be increased. For this reason, even if the louver pitch LP is made fine, clogging of the louver 23 can be suppressed. Further, since the cooling air can be reliably guided to the inter-louver passage 5 formed in the adjacent louver 23, the heat transfer rate per louver can be improved.

  Furthermore, since the upstream end of each louver 23 can be disposed at a portion where low-temperature air flows, the tip effect can be satisfactorily exhibited in each louver 23, and the heat transfer coefficient of the corrugated fin 2 can be increased. Can be improved.

  Further, the center points 24 in the louver width direction X4 of the plurality of louvers 23 are arranged on the same straight line Z, and the straight line Z is inclined with respect to the center line Y in the fin plate thickness direction X2, thereby providing a distance between the louvers. Since the distance LD can be made equal, the cooling air flow in each part of the louver 23 can be made equal, and heat exchange can be promoted.

  Further, a line segment connecting the center point 24 of the louver 23 arranged on the most upstream side of the cooling air flow and the center point 24 of the louver 23 arranged on the most downstream side of the cooling air flow is represented by a fin plate thickness direction X2. The amount of offset can be increased by intersecting the center line Y. For this reason, since the distance LD between louvers can be made larger, even if the louver pitch LP is made fine, clogging of the louvers 23 can be reliably suppressed and the heat transfer rate per louver can be further improved. it can.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIG. The same parts as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted.

  FIG. 4 is a cross-sectional view of the corrugated fin 2 according to the second embodiment as viewed from the tube stacking direction X3. In the present embodiment, the two-dot chain line in FIG. 4 indicates the center line Y of the corrugated fin 2 in the fin plate thickness direction X2.

  As shown in FIG. 4, in this embodiment, the twist directions of all the louvers 23 are equal. That is, the twisting direction of the louver 23 belonging to the upstream louver group is equal to the twisting direction of the louver 23 belonging to the downstream louver group. The center points 24 of all the louvers 23 in the louver width direction X4 are arranged on the same straight line Z, and the straight line Z is inclined with respect to the center line Y in the fin plate thickness direction X2.

  Further, among all the louvers 23, a line segment connecting the center point 24 of the louver 23 arranged on the most upstream side of the cooling air flow and the center point 24 of the louver 23 arranged on the most downstream side of the cooling air flow. Intersects the center line Y in the fin plate thickness direction X2. That is, the center points 24 of the plurality of louvers 23 in the louver width direction X4 are arranged on one side and the other side of the plate thickness direction X4 with respect to the center line Y of the fin plate thickness direction X2 center line.

  Thereby, the effect similar to the said 1st Embodiment can be acquired.

(Other embodiments)
In each of the above embodiments, the example in which the offset amounts of all the louvers 23 are the same has been described. However, the present invention is not limited to this example. For example, the offset amount of a portion through which cooling air is difficult to pass is increased. You may make small the amount of offsets of the part which service air passes easily.

It is a front view which shows the radiator in 1st Embodiment. It is sectional drawing which looked at the corrugated fin 2 which concerns on 1st Embodiment from the tube lamination direction X3. It is the A section enlarged view of FIG. It is sectional drawing which looked at the corrugated fin 2 which concerns on 2nd Embodiment from the tube lamination direction X3.

Explanation of symbols

  21 ... plane part, 23 ... louver, X1 ... air flow direction (fluid flow direction), X2 ... fin plate thickness direction.

Claims (6)

A heat transfer member that is formed from a thin plate member and is placed in a fluid to transfer heat to and from the fluid,
A plane portion (21) substantially parallel to the fluid flow direction (X1),
The plane portion (21) is provided with a plurality of louvers (23) twisted at a predetermined angle (θ ₀ ) with respect to the plane portion (21) along the fluid flow direction (X1). And
The adjacent louvers (23) are offset from each other in the plate thickness direction (X2),
The plurality of louvers (23) are shifted in the same direction when viewed from the fluid flow direction (X1) so that the distance (LD) between the adjacent louvers (23) is increased. A heat transfer member. When the direction along the predetermined angle (θ ₀ ) is the louver width direction (X4),
In the plurality of louvers (23), an angle formed by a line (Z) connecting the center points (24) of the louver width direction (X4) between the adjacent louvers (23) and the louver width direction (X4) ( The heat transfer member according to claim 1, wherein θ ₁ ) is larger than the predetermined angle (θ ₀ ). When the direction along the predetermined angle (θ ₀ ) is the louver width direction (X4),
The center point (24) of the louver width direction (X4) in the plurality of louvers (23) is arranged on the same straight line (Z),
The heat transfer member according to claim 1 or 2, wherein the straight line (Z) is inclined with respect to a center line (Y) in the plate thickness direction (X2). Of the plurality of louvers (23), the center point (24) of the louver (23) disposed on the most upstream side of the fluid flow and the louvers (23) disposed on the most downstream side of the fluid flow. The heat transfer member according to claim 2 or 3, wherein a line connecting the center point (24) intersects the center line (Y) in the plate thickness direction (X2). 5. The device according to claim 1, wherein the flat portion is formed in a wave shape so as to have a curved portion connecting the adjacent flat portions. Heat transfer member as described in 1. A heat exchanger comprising a plurality of tubes (1) through which a heat medium flows and fins (2) joined to the outer surface of the tubes (1) to promote heat exchange of the heat medium,
The heat exchanger according to claim 1, wherein the fin (2) is a heat transfer member according to any one of claims 1 to 5.

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