JP2000220980A - Flat tube for heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flat tube for a heat exchanger for further improving a heat exchanging efficiency by providing only many beads. SOLUTION: In the flat tube 1 for a heat exchanger comprising a flat tube body 2 in which a heat exchange medium flows therein, and many beads 5 for coupling both flat surfaces opposed to each other in the body 2 to generate a turbulent flow of the medium in the body 2, lands 6 protruding from at least one of both the flat surfaces into the body 2 and a flowing air gap in which the medium flows over the lands 6 are formed between the beads 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat tube for a heat exchanger used for a heat exchanger such as a condenser, an evaporator, a heater core, or a radiator for a vehicle used in a refrigeration cycle of an air conditioner for a vehicle or the like. It is.

[0002]

2. Description of the Related Art FIG. 8 shows an example of a conventional product. This flat tube A for a heat exchanger is disclosed in JP-A-7-19774.
In this publication, a flat tube body B through which a heat exchange medium flows, and two opposed flat planes C, C in the tube body B are connected to each other, and heat is generated in the tube body B. And a number of cylindrical beads D for generating a turbulent flow of the exchange medium. At a portion near the U-shaped bent portion B1 of the tube main body B, the two deflected planes C, C near the bent portion B1 are connected along the longitudinal direction X of the tube main body B to reinforce the bent portion B1. A protrusion E is formed.

In this flat tube A, a tube body B
Since the heat exchange medium flowing inside the laminar flow is disturbed by the large number of beads D and flows while generating turbulent flow, the heat exchange efficiency can be improved.

[0004]

However, in the flat tube A, the turbulent flow of the heat exchange medium generated by the large number of beads D only disturbs the laminar flow state of the heat exchange medium almost flatly. The effect of disturbing the temperature boundary layer of the heat exchange medium formed in the vicinity of the two planes C, C by this turbulence is small. Therefore, there is a limit in improving the heat exchange efficiency.

Accordingly, an object of the present invention is to provide a flat tube for a heat exchanger which can further improve the heat exchange efficiency as compared with a conventional product.

[0006]

According to a first aspect of the present invention, a flat tube body through which a heat exchange medium flows and two opposed flat surfaces inside the tube body are connected to each other to form a heat exchange medium in the tube body. In a flat tube for a heat exchanger with a number of beads generating a turbulence of
A land portion protruding into the tube body from at least one of the two planes and a flow gap through which the heat exchange medium flows over the land portion are formed.

According to a second aspect of the present invention, there is provided the flat tube for a heat exchanger according to the first aspect, wherein the lands are formed so as to bridge between the beads.

According to a third aspect of the present invention, there is provided the flat tube for a heat exchanger according to the first or second aspect, wherein a bead arrangement in which beads are intermittently arranged in a longitudinal direction of the tube main body. In both bead arrangements formed in a plurality of rows and adjacent to each other, the beads of one bead arrangement are located between the beads of the other bead arrangement, and the land portion is one bead arrangement in one bead arrangement and both sides of the one bead arrangement In both bead arrangements adjacent to the one bead, the heat exchange medium is formed in all sections with the beads adjacent to the upstream and downstream of the heat exchange medium with respect to the one bead, thereby being formed between all the beads. It is characterized by:

According to a fourth aspect of the present invention, there is provided the flat tube for a heat exchanger according to the first or second aspect, wherein a bead arrangement in which beads are intermittently arranged in a longitudinal direction of the tube main body. In both bead arrangements formed in a plurality of rows and adjacent to each other, the beads of one bead arrangement are located between the beads of the other bead arrangement, and the land portion is one bead arrangement in one bead arrangement and both sides of the one bead arrangement In the bead arrangement adjacent to any one side, while being formed between the one bead and the bead adjacent to any one of the upstream side or the downstream side of the flow of the heat exchange medium, The one bead in the one bead arrangement, and the bead arrangement adjacent to either one of the two sides of the one bead arrangement, any one of a flow upstream side and a flow downstream side of the heat exchange medium with respect to the one bead. Or the other Is characterized in that by being formed between the bead adjacent, it is formed between all bead.

According to a fifth aspect of the present invention, there is provided the flat tube for a heat exchanger according to the third or fourth aspect, wherein the beads are arranged at regular intervals in the longitudinal direction of the tube main body, and the two adjacent bead arrays are arranged. Is characterized in that the beads of one bead arrangement are located midway between the beads of the other bead arrangement.

According to a sixth aspect of the present invention, there is provided the flat tube for a heat exchanger according to any one of the first to fifth aspects, wherein the land portion has an arc-shaped cross-sectional surface. .

[0012]

According to the first aspect of the present invention, the heat exchange medium flows while being disturbed in the laminar flow state by a large number of beads, and flows over the land protruding into the tube main body from at least one of the two planes. . Then, the heat exchange medium flowing over the land portion flows down from the top of the land portion toward the uneven surface, and can disturb the temperature boundary layer of the heat exchange medium formed near the uneven surface. Therefore, compared with the conventional product having only a large number of beads, the temperature boundary layer of the uneven surface of the tube body performing the heat exchange can be thinned, and the heat exchange efficiency can be further improved.

According to the second aspect of the invention, in addition to the effect of the first aspect, since the land portion bridges between the beads,
The heat exchange medium flowing between the beads where the lands are cross-linked reliably flows down from the top of the lands toward the uneven plane, and thus ensures the temperature boundary layer of the heat exchange medium formed near the uneven plane. The heat exchange efficiency can be reliably improved.

According to the third aspect of the invention, in addition to the effects of the first and second aspects, the bead portion and the land portion are arranged so as to obliquely intersect with the longitudinal direction of the tube main body. Since it is performed on the bead, a large number of substantially rectangular regions having four sides oblique to the longitudinal direction of the tube main body can be formed on at least one of the two planes, and each region has heat. The temperature boundary layer of the exchange medium can be disturbed. Therefore, the heat exchange efficiency can be further improved.

According to a fourth aspect of the present invention, in addition to the effects of the first and second aspects of the present invention, the bead portion and the land portion are arranged so as to be inclined with respect to the longitudinal direction of the tube main body. Therefore, a land region in which the bead portion and the land portion are arranged obliquely with respect to the longitudinal direction of the tube main body on at least one of the two planes,
It is possible to alternately form a flow area extending along the land area and having no land.

Therefore, the temperature boundary layer of the heat exchange medium can be disturbed by the heat exchange medium flowing over the land portion of the land area, and the heat exchange medium can flow smoothly into the circulation area, thereby improving the heat exchange efficiency. It is possible to achieve both improvement and reduction in distribution resistance.

According to the fifth aspect of the invention, in addition to the effects of the third and fourth aspects, the beads are arranged at equal intervals along the longitudinal direction of the tube main body. Since the beads of the array are located in the middle between the beads of the other bead array, the distribution density of the beads can be increased, and the heat exchange efficiency can be further improved and the pressure resistance of the tube body can be improved. it can.

According to the sixth aspect of the present invention, in addition to the effects of the first to fifth aspects, since the land portion has an arc-shaped cross section, the flow resistance of the heat exchange medium flowing over the land portion is reduced. Therefore, the flow resistance can be reduced.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) FIG. 1 shows a first embodiment in which each of the first, second, third, fifth and sixth aspects of the present invention is implemented.
It is a top view showing an example of an embodiment. FIG. 2 is a sectional view taken along line VV of FIG. As shown in FIGS. 1 and 2, a flat tube 1 for a heat exchanger includes a flat tube main body 2 through which a heat exchange medium flows, and two flat flat surfaces 3 and 4 in the tube main body 2 facing each other. A plurality of beads 5 connected to each other to generate a turbulent flow of the heat exchange medium in the tube body 2.

The bead 5 extends in the longitudinal direction X of the tube body 2.
It has an elliptical cylindrical shape having a major axis extending along the center line, and projects from one of the two flat surfaces 3 and 4 into the tube body 2 and is joined to the other flat surface 4. Land portions 6 projecting into the tube body 2 together with the beads 5 from the uneven plane 3 and bridging between the beads 5 between the adjacent beads 5,
Flow gap 7 through which heat exchange medium flows over land 6
Are formed.

At one end of the tube body 2 in the longitudinal direction X,
An inflow port (not shown) through which the heat exchange medium flows into the tube body 2 is formed.
An outflow port (not shown) through which the heat exchange medium flows out of the tube body 2 is formed.

This flat tube 1 is formed by bending a single rectangular plate P from both sides in the width direction.
Are brazed at the center of the plate P at both ends in the width direction.

On the plate P, a large number of protrusions T for the beads 5 are formed in advance at predetermined positions on the plate surfaces that become the two flat surfaces 3 and 4 after processing by dimple processing.
These projections T have their top surfaces brazed to the uneven plane 4 during the bending of the plate P to form beads 5. In addition, the plate surfaces that become the two flat surfaces 3 and 4 after processing are provided with land portions 6 between protrusions T for beads 5 adjacent to each other.
Many are also formed in advance by dimple processing.

As shown in FIG. 1, in the flat tube 1,
A plurality of rows of beads are formed in which beads 5 are arranged at equal intervals along the longitudinal direction X of the tube body 2. Then, in both bead arrangements adjacent to each other, the beads 5 in one bead arrangement are located in the middle between the beads 5 in the other bead arrangement.

The land portion 6 includes one bead 5 in one bead arrangement, and a flow upstream and downstream of the heat exchange medium with respect to the one bead 5 in both bead arrangements adjacent to both sides of the one bead arrangement. By being formed in the entire section with the bead 5 adjacent to each side, the entire bead 5 adjacent to each other is bridged.

Therefore, in the flat tube 1, the lands 6 and the beads 5 are arranged so as to obliquely intersect with the longitudinal direction X of the tube main body 2. In addition, in FIG. 2, the symbol H indicates the distance between the two deflected planes 3 and 4, and the symbol h
Indicates the protruding height of the land portion 6 from the uneven plane 3.

FIG. 3 is a perspective view showing the main part of the tube shown in FIG. As shown in FIG. 3, in the flat tube 1, the heat exchange medium flows while being disturbed in the laminar flow state by the large number of beads 5, and flows while passing over the lands 6.

Since the heat exchange medium flowing over the land 6 flows down from the top of the land 6 toward the plane 3, it disturbs the temperature boundary layer of the heat exchange medium formed near the plane 3. be able to. Therefore, the temperature boundary layer of the heat exchange medium can be made thinner and the heat exchange efficiency can be further improved as compared with the conventional product shown in FIG.

Moreover, in the flat tube 1, the land 6
Is bridged between all the beads 5, so that the heat exchange medium flowing between the beads 5 surely flows down from the top of the land portion 6 toward the uneven plane 3. Therefore, it is possible to reliably disturb the temperature boundary layer of the heat exchange medium formed near the uneven plane 3.

In addition, in the flat tube 1, the land portions 6 and the beads 5 are arranged so as to obliquely intersect with the longitudinal direction X of the tube main body 2.
A large number of substantially rhombic regions R having four sides oblique to the longitudinal direction X of the tube main body 2 are formed.
In each case, the temperature boundary layer can be reliably disturbed. Therefore, the heat exchange efficiency can be reliably improved as compared with the conventional product shown in FIG.

In the flat tube 1, beads 5 are arranged at equal intervals along the longitudinal direction X of the tube body 2.
In the two bead arrangements adjacent to each other, since the beads 5 of one bead arrangement are located in the middle between the beads 5 of the other bead arrangement, the distribution density of the beads 5 can be increased, and the heat exchange efficiency can be improved. The pressure resistance of the tube body 2 can be improved.

Further, in the flat tube 1, as shown in FIG. 3, the land 6 has an arc-shaped cross section, so that the flow resistance of the heat exchange medium flowing over the land 6 is reduced. be able to. In addition, bead 5
Has an elliptical cylindrical shape having a major axis along the longitudinal direction X of the tube main body 2, so that the flow resistance of the heat exchange medium flowing along the outer peripheral surface of the bead 5 can be reduced. Therefore, the flow resistance can be reduced.

The height h of the land 6 shown in FIG.
It is preferably 10 to 60% of the distance H between the two deflected planes 3 and 4. This is because if the height h of the land 6 is less than 10% of the distance H between the two planes 3 and 4, the temperature boundary layer due to the heat exchange medium flowing down from the top of the land 6 toward the plane 3 is formed. If the height h of the land 6 exceeds 60% of the distance H between the planes 3 and 4, the flow resistance becomes too large.

(Second Embodiment) FIG.
It is a top view which shows an example of 2nd Embodiment which implemented each invention of 4-6 together. FIG. 5 is a perspective view showing the main part in the tube shown in FIG. In the following description of the second embodiment, the same components as those of the first embodiment are denoted by the same reference numerals, and the description overlapping with the description of the first embodiment will be omitted.

As shown in FIGS. 4 and 5, the flat tube 1
In the case of 0, the land portion 6 has one bead 5 in one bead arrangement.
A bead array adjacent to the one bead 5 on the upstream side of the heat exchange medium in the bead array adjacent to the right side from the upstream side of the heat transfer medium to the downstream side of the one bead array. And are cross-linked.

The land portion 6 includes one bead 5 in one bead arrangement and the bead arrangement in the bead arrangement adjacent to the one bead arrangement on the left side from the upstream side of the flow of the heat transfer medium toward the downstream side of the flow. One bead 5 is cross-linked to a bead 5 adjacent to the downstream side of the flow of the heat exchange medium. In this manner, the land portions 6 bridge all the spaces between the adjacent beads 5.

For this reason, in the flat tube 10, the land area L in which the beads 5 cross-linked by the land portions 6 are arranged obliquely to the longitudinal direction X of the tube body 2 on the flat surface 3.
And the flow region M extending along the land region L and having no land portion 6 can be formed alternately. Accordingly, the heat exchange medium flows inside the tube body 2 while passing over the land portions 6 of the land region L, and also flows through the flow region M without the land portions 6.

The heat exchange medium flowing over the land portion 6 can disturb the temperature boundary layer of the heat exchange medium formed in the vicinity of the uneven plane 3, and the heat exchange medium flowing through the flow area M is Because of the absence of the part 6, the fluid flows smoothly. Therefore, in the flat tube 10, both improvement in heat exchange efficiency and reduction in flow resistance can be achieved.

FIG. 6 is a plan view showing another example of the second embodiment. As shown in FIG.
At the both ends in the width direction, reinforcing projections 21 projecting from the uneven plane 3 and fixed to the uneven plane 4 and extending along the longitudinal direction X of the tube main body 2 are formed.

Therefore, in the flat tube 20, both U-shaped bent portions 22 formed at both ends in the width direction of the tube main body 2 can be reinforced by the reinforcing projections 21. In addition,
This reinforcing projection 21 may be provided, for example, at the center of the tube main body 2 or may be provided on the flat tube 1 of the first embodiment.

By the way, the flat tubes 1 and 2 described above
In 10, 20, the bead 5 has an elliptical cylindrical shape. However, the bead 5 is not limited to an elliptical cylindrical shape, and may be, for example, a circular cylindrical shape, a prismatic shape, a two-stage shape or a multi-stage shape having a step in the middle, the tube body 2.
May be elongated along the longitudinal direction X. Further, beads 2 having various shapes may be combined. However, it is preferable that the beads 5 have a columnar shape, since the flow resistance of the heat transfer medium is reduced.

In the flat tubes 1, 10, and 20,
The land 6 has an arc-shaped cross section on the surface. However, the cross-sectional shape of the surface of the land portion 6 is not limited to an arc shape, and may be, for example, a dihedral shape, a polyhedral shape, or the like. However, it is preferable that the land portion 6 has an arc-shaped cross section on the surface since the flow resistance is reduced.

In the flat tubes 1, 10, and 20,
The bead 5 and the land 6 are formed so as to protrude from the uneven plane 3. However, the bead 5 and the land portion 6 may be formed so as to protrude from the two planes 3 and 4 or may be formed so as to protrude from the plane 4. Alternatively, the bead 5 may be arranged and fixed between the two planes 3 and 4, and the land 6 may be arranged and fixed on at least one of the planes 3 and 4.

Further, in the flat tubes 1, 10, and 20,
The land portions 6 bridge between adjacent beads 5. However, as shown in FIG. 7, the land portions 6 may be formed between the adjacent beads 5 without bridging between the adjacent beads 5. The beads 5 bridged by the lands 6 or the beads 5 between which the lands 6 are formed may or may not be adjacent to each other. However, it is preferable that they are adjacent to each other because heat exchange efficiency can be efficiently improved.

In addition, the flat tubes 1, 10, 20
Although it is formed by bending one plate P, for example, it may be formed by overlapping two plates. And, of course, the flat tubes 1, 10, and 20 can be diverted to, for example, a tube portion of a known Drone cup type heat exchanger.

[Brief description of the drawings]

FIG. 1 is a plan view showing an example of an embodiment of the present invention.

FIG. 2 is a sectional view taken along line VV of FIG.

FIG. 3 is a perspective view showing a main part of the one shown in FIG.

FIG. 4 is a plan view showing another example of the embodiment of the present invention.

FIG. 5 is a perspective view showing a main part of the one shown in FIG.

FIG. 6 is a plan view showing still another example of the embodiment of the present invention.

FIG. 7 is a perspective view showing a main part of still another example of the embodiment of the present invention.

FIG. 8 is a perspective view showing an example of a conventional product.

[Explanation of symbols]

 1, 10, 20 Flat tube 2 Tube main body 3, 4 Uneven plane 5 Bead 6 Land part 7 Flow gap X Longitudinal direction

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yoshihiro Sasaki 5-24-15 Minamidai, Nakano-ku, Tokyo Calsonic Co., Ltd. (72) Inventor Misaki Koga 5-24-15 Minamidai, Nakano-ku, Tokyo Calso Nick Corporation

Claims (6)

[Claims] 1. A flat tube body (2) through which a heat exchange medium flows, and two opposing flat surfaces (3, 4) in the tube body (2) are connected to each other and connected in the tube body (2). A flat tube for a heat exchanger including a plurality of beads (5) for generating a turbulent flow of a heat exchange medium, wherein a tube body (5) is provided between at least one of the flat surfaces (3, 4) between the beads (5). 2) A flat tube for a heat exchanger, wherein a land portion (6) protruding inward and a flow gap (7) through which a heat exchange medium flows over the land portion (6) are formed. 2. The flat tube for a heat exchanger according to claim 1, wherein the land portion (6) bridges between the beads (5). 3. The flat tube for a heat exchanger according to claim 1, wherein a bead (5) is intermittently provided in the tube body (2) along a longitudinal direction (X) of the tube body (2). In a bead arrangement adjacent to each other, the beads (5) of one bead arrangement are located between the beads (5) of the other bead arrangement, and the land portion (6) , One bead in one bead array (5)
And a bead (5) adjacent to the one bead (5) in the upstream and downstream sides of the heat exchange medium in both bead arrays adjacent to both sides of the one bead array. A flat tube for a heat exchanger, wherein the flat tube is formed between all the beads (5). 4. The flat tube for a heat exchanger according to claim 1, wherein a bead (5) is intermittently provided in the tube body (2) along a longitudinal direction (X) of the tube body (2). In a bead arrangement adjacent to each other, the beads (5) of one bead arrangement are located between the beads (5) of the other bead arrangement, and the land portion (6) , One bead in one bead array (5)
And adjacent to either one of the upstream side and the downstream side of the flow of the heat exchange medium with respect to the one bead (5) in the bead arrangement adjacent to one of the two sides of the one bead arrangement. And one bead (5) in the one bead arrangement and a bead arrangement adjacent to the other side on either side of the one bead arrangement.
A bead (5) adjacent to the other side of the heat exchange medium, either upstream or downstream of the one bead (5).
A flat tube for a heat exchanger, wherein the flat tube is formed between all the beads (5). 5. The flat tube for a heat exchanger according to claim 3, wherein the bead (5) is arranged in a longitudinal direction (X) of the tube body (2).
In the two bead arrangements which are arranged at equal intervals along each other and which are adjacent to each other, the beads (5) of one bead arrangement are located in the middle between the beads (5) of the other bead arrangement. Flat tube for exchanger. 6. The flat tube for a heat exchanger according to claim 1, wherein the land (6) has an arc-shaped cross section on its surface. Flat tube for dexterity.