US20070151716A1

US20070151716A1 - Heat exchanger and fin of the same

Info

Publication number: US20070151716A1
Application number: US11/647,471
Authority: US
Inventors: Han Lee; Dong Jang; Sang Lee; Ju Kim; Yong Sa
Original assignee: LG Electronics Inc
Current assignee: LG Electronics Inc
Priority date: 2005-12-30
Filing date: 2006-12-29
Publication date: 2007-07-05

Abstract

A heat exchanger and a fin of the same are provided. The heat exchanger includes a tube, a plurality of fins, a slit section, and a condensed water guide. The tube is arranged in at least a front row and a rear row with respect to a direction of airflow. The plurality of fins is installed with the tube passing therethrough. The slit section is formed on the fins and includes a plurality of slits. The condensed water guide is formed between at least the front row and the rear row, for guiding a draining of condensed water that is generated on a surface of the tube. A fin of the heat exchanger includes a plurality of tube insert holes, a slit section, and a condensed water guide. A refrigerant tube is inserted in the plurality of tube insert holes. The slit section includes a plurality of slits formed around the tube insert holes. The condensed water guide is formed at a rear side of one of the slits, and guides a draining of condensed water generated in a heat exchange process between refrigerant and air.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention
The present invention relates to a fin of a heat exchanger, and more particularly, to a heat exchanger and a fin of the same for promptly draining condensed water to increase a heat exchanging efficiency of the heat exchanger and prevent a carry-over phenomenon where condensed water overflows into an indoor area.
2. Description of the Related Art
In general, a heat exchanger is an apparatus for exchanging heat between refrigerant and air, and has various applications including air conditioners. Heat exchangers are mainly embodied in the form of finned tubes.
In a heat exchanger according to a related art, a plurality of fins is vertically stacked and spaced from each other by a predetermined distance. A tube is installed through the fins and bent multiple times, through which refrigerant circulates. The fin is installed perpendicular to the tube to expand an area of heat exchange between the refrigerant and air that pass through and around the tube.
Here, the fin is planar in form. Fin collars are arranged in a zigzag pattern along the length of the fin so that the tube can be inserted into the fins.
However, when air flows along the plate fin, working fluid collides against the front end of the fin to flow in a parabolic form and form a thick hydraulic boundary. As a result, heat exchanging efficiency decreases as the working fluid approaches the rear part of the fin.
Accordingly, a recent improvement uses a plurality of slits formed in a surface of the fin to form a relatively thin hydraulic boundary, increasing heat-exchanging efficiency.
The function of the above heat exchanger according to a related art will be described below.
When a heat exchanger is used as an evaporator, refrigerant first flows into the heat exchanger, and a fan mounted at one side of the heat exchanger forces outer air past the surface of the fin. As a result, the outer air loses its heat by means of the tube in which the refrigerant flows. Thus, cool air is generated in this way to drop the temperature of a room.
After a while, in the course of the heat exchange, when air flows by the surface of the fin of the heat exchanger, condensed water is generated by the reaction of air with the cooling fin of the heat exchanger. Also, the amount of condensed water generated is much greater at the front of the heat exchanger than at the rear.
However, a plurality of slits in the structure of the heat exchanger fin according to a related art prevents condensed water from flowing, so that the condensed water cannot drain quickly away. Such condensed water becomes a heat insulating layer between the surface of the heat exchanger and the outer air, decreasing the efficiency of the heat exchanger for heat transfer.
Further, when the condensed water does not drain quickly, the condensed water generated on the surface of the fin may flow into an indoor area from the rear of the fin, that is, the end portion of an air outlet.

SUMMARY OF THE INVENTION

Accordingly, the present invention is directed to a heat exchanger and a fin of the same that substantially obviate one or more problems due to limitations and disadvantages of the related art.
An object of the present invention is to provide a heat exchanger and a fin for promptly draining condensed water generated on a surface of a fin.
Another object of the present invention is to provide a heat exchanger and a fin for improving the efficiency of the heat exchanger due to condensed water draining away easily.
Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
To achieve these objects and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, there is provided a heat exchanger including: a tube arranged in at least a front row and a rear row with respect to a direction of airflow; a plurality of fins installed with the tube passing therethrough; a slit section formed on the fin and including a plurality of slits; and a condensed water guide formed between at least the front row and the rear row, for guiding a draining of condensed water that is generated on a surface of the tube.
In another object of the present invention, there is provided a fin of a heat exchanger including: a plurality of tube insert holes into which a refrigerant tube is inserted; a slit section including a plurality of slits formed around the tube insert holes, and a condensed water guide formed at a rear side of one of the slits, for guiding a draining of condensed water generated in a heat exchange process between refrigerant and air.
In a further object of the present invention, there is provided fin of a heat exchanger including: a plurality of tube insert holes formed in two or more rows at a front and a rear with respect to an airflow direction; and a first and a second condensed water guide for guiding a drainage of condensed water generated during a heat exchange process between air and refrigerant in the tube, wherein the first condensed water guide is formed at a rear of a center of a front tube insert hole with respect to the airflow direction, and the second condensed water guide is formed at a rear of center of a rear tube insert hole with respect to the airflow direction.
An advantage of the present invention is the promp draining away of condensed water generated on a surface of a fin to prevent the condensed water from flowing into an indoor area.
Another advantage of the present invention is that heat exchanging efficiency is improved through prompt drainage of the condensed water to reduce power consumption of the heat exchanger.
It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiments of the invention and together with the description serve to explain the principle of the invention. In the drawings:
FIG. 1 is a perspective view of a heat exchanger according to the present invention;
FIG. 2 is a top view showing the structure of a heat exchanger fin;
FIG. 3 is a cross-sectional view taken along line I-I′ of FIG. 2; and
FIG. 4 is a top view showing condensed water flowing along a condensed water guide on a fin surface.

DETAILED DESCRIPTION OF THE INVENTION

Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.
FIG. 1 is a perspective view according to the present invention.
Referring to FIG. 1, a heat exchange 1 includes a tube 10 arranged with at least a front and a rear row, a plurality of fins 20 installed through the fin 10.
In detail, the tube 10, through which refrigerant flows, has a predetermined length and is bent multiple times. Also, the fins are spaced from each other at a predetermined distance and are perpendicular to the tube.
Here, a front and a rear row tube are arranged in a zigzag pattern to promote heat exchange at each tube.
The fin 20 is formed of a thin plate to expand a heat transfer area that contacts air and improves the efficiency of heat transfer.
Also, a plurality of slits is formed on at least one side of the fin. Condensed water guides 41 and 42 are formed to guide drainage of condensed water generated on a surface of the fin.
The operation of the heat exchanger 1 according to the above embodiment will be described. First, refrigerant flows in the tube 10. Then, while the refrigerant is flowing, air streams into a front row tube to exchange heat and flows out of the rear row tube.
In the course of the heat exchange, condensed water is generated on the surface of the fin 20, and drains downwardly along the condensed water guides 41 and 42 on the surface of the fin 20.
FIG. 2 is a top view showing the structure of a heat exchanger fin.
Referring to FIG. 2, the fin 20 is divided into a front row fin 21 that the front row tube 10 penetrates and a rear row fin 21 that the rear row tube penetrates.
Also, a plurality of tube insert holes into which the tube 10 can be inserted is formed on a surface of the fin 20.
Also, the tube insert holes 11 and 12 are spaced from each other at a predetermined distance. The tube insert hole 11 on the front row fin 21 and the tube insert hole 12 on the rear row fin 22 are arranged in a zigzag pattern relative to each other.
In this way, the tube insert hole 12 on the rear row fin 22 is arranged between the tube insert holes 11 on the front row fin 21, so that each tube 10 can achieve a desired level of heat exchange.
Also, a fin collar 13 is formed around the tube insert holes 11 and 12, and extends from a rear side or a front side, so that the tube 10 can be easily inserted into and firmly secured to the tube insert hole.
A front slit area A and a rear slit area B including a plurality of slits are formed along a length of the fin 20 between the tube insert holes 11 and 12.
Also, based on an air flowing direction, a front and a rear condensed water guides 41 and 42 are formed at rear of each of the tube insert holes 11 and 12. Specifically, each end of the front row fin 21 and the rear row fin 22 guides drainage of condensed water.
In detail, the front row slit area A has three or less slit rows to improve drainage of the condensed water, while the rear row slit area B has four or more slit rows.
When air flows into the heat exchanger 1, most condensation of water occurs on the front row fin 21 of the fin 10, where a temperature difference between refrigerant and air is relatively broad. Accordingly, the front row slit area A is configured to include three or less slits to reduce flow resistance of the condensed water.
In other words, the number of slits formed on the front row fin 21 is less than the number on the rear row fin 22. As a result, a pattern of slits at the front row fin 21 and slits of the rear row fin 22 is asymmetric.
Further, for good drainage of the condensed water from the front row fin 21, it is preferable that a gap between slits in the front row slit area A is greater than that in the rear row slit area B.
In particular, the front row slit area A includes a first row that has a plurality of short slits 22 and 23 based on an air flow direction, a second row that has a single long slit and a third row that has a plurality of short slits 26 and 27.
The rear row slit area B includes a first row that has a plurality of short slits 71 and 72, a second and a third row that have a single long slit 73 and 74 respectively, and a fourth row that has a plurality of short slits 75 and 76.
Since the less water condenses on the rear row slit area B, here, it is more important to dissipate the heat boundary between air and a surface of the fin 10. Accordingly, four or more of slits are formed on the rear row slit area B to increase the surface area contacting air and dissipate the heat boundary.
Meanwhile, the front row guide 41 is formed between the centerline C of the fin and the centerline C1 of the tube insert hole 11 formed on the front row fin 21. The rear row guide 42 is formed between the rear end line B of the fin and the centerline C2 of the tube insert hole 12 formed on the rear row fin 22.
Next, the condensed water guides 41 and 42 are disposed at a predetermined angle with respect to an airflow direction. The condensed water guides 41 and 42 extend vertically along the length of the fin 20. It is preferable that the condensed water guides 41 and 42 are the same length as the fin 20.
FIG. 3 is a cross-sectional view taken along line I-I′ of FIG. 2.
Referring to FIG. 3, the condensed water guides 41 and 42 are protruded or depressed by a predetermined height H from the surface of the fin 20. It is apparent that these condensed water guides 41 and 42 may be press-formed, but the forming method thereof is not limited thereto.
Also, the condensed water guides 41 and 42 have a triangular or semicircular sectional profile. Here, the sectional profile of the condensed water guides 41 and 42 is triangular as shown in FIG. 3.
Here, the condensed water guides 41 and 42 include both protruded and depressed parts.
Accordingly, condensed water generated on the surface of the fin 20 flows downwardly along the protruded parts of the condensed water guides 41 and 42, or may flow downwardly through the depressed parts of the condensed water guides 41 and 42.
In other words, the condensed water guides 41 and 42 with different shapes are formed at a front side and a rear side.
Here, the protruded height H of the condensed water guides 41 and 42 is preferably 0.3 to 0.6 mm. That is, when the height is below 0.3 mm, the problem of condensed water flowing over the condensed water guide 41 and 42 occurs. On the other hand, when the height is above 0.6 mm, the problem of a reduction in heat exchanging efficiency occurs due to the obstruction of airflow.
Here, according to an embodiment of the present invention, press-forming is used to form the condensed water guide 41 and 42. Alternately, a separate member may be combined with the surface of the fin.
The operation of the heat exchanger having the above configuration will now be explained.
FIG. 4 is a top view showing condensed water flowing along a condensed water guide on a fin surface.
Referring to FIG. 4, during the operation of the heat exchanger according to the present invention, refrigerant flows in the tube 10. The refrigerant transfers heat to the fin 20. The fin 20 exchanges heat with the air.
Then, in the course of the heat exchange, condensed water W forms on the surface of the fin 20. This condensed water W streams down by gravity along the surface of the fin 20. In detail, one portion of the condensed water W flows along a circumferential surface of the fin collar 13 and a circumferential surface of the tube 10, while another portion of the condensed water W flows to the rear of the fin 20 by means of the airflow.
Meanwhile, condensed water W formed at a front of centerline C of the fin 20 is pushed to the front row guide 41, and then promptly streams down along the front row guide 41. In this way, the heat-isolating phenomenon disappears. As a result, the efficiency of the fin 20 improves.
On the other hand, condensed water W formed at a rear of centerline C of the fin 20 is pushed to the rear row guide 42, and then promptly streams down along the rear row guide 42. In this way, the condensed water W is prevented from flowing into an indoor area.
It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention. Thus, it is intended that the present invention covers the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.

Claims

1. A heat exchanger comprising:

a tube arranged in at least a front row and a rear row with respect to a direction of airflow;

a plurality of fins installed with the tube passing therethrough;

a slit section formed on the fin and including a plurality of slits; and

a condensed water guide formed between at least the front row and the rear row, for guiding a draining of condensed water that is generated on a surface of the tube.

2. The heat exchanger according to claim 1, wherein the condensed water guide protrudes a predetermined height from the surface of a fin.

3. The heat exchanger according to claim 1, wherein the condensed water guide is depressed by a predetermined depth.

4. The heat exchanger according to claim 1, wherein the condensed water guide is formed along a length of the fin.

5. The heat exchanger according to claim 1, wherein the condensed water guide is disposed at a predetermined angle with respect to the direction of airflow.

6. The heat exchanger according to claim 1, wherein the condensed water guide is press-formed.

7. The heat exchanger according to claim 1, further comprising another condensed water guide provided at a rear side of the rear row.

8. The heat exchanger according to claim 7, wherein the condensed water guides are parallel to each other.

9. The heat exchanger according to claim 1, wherein the slit section comprises:

a front row slit section formed around the fin into which the front row tube is inserted; and

a rear row slit section formed around the fin into which the rear row tube is inserted, the front row slit section having a smaller number of slit rows formed therein than the rear row slit section.

10. The heat exchanger according to claim 1, wherein the slit section comprises:

a rear row slit section formed around the fin into which the rear row tube is inserted, the front row slit section having wider intervals between slits than the rear row slit section.

11. The heat exchanger according to claim 1, wherein the condensed water guide has a length that is substantially equal to a vertical length of the fin.

12. A fin of a heat exchanger comprising:

a plurality of tube insert holes into which a refrigerant tube is inserted;

a slit section including a plurality of slits formed around the tube insert holes, and

a condensed water guide formed at a rear side of one of the slits, for guiding a draining of condensed water generated in a heat exchange process between refrigerant and air.

13. The fin of the heat exchanger according to claim 12, wherein the condensed water guide is formed at a rear of a center of the tube insert hole with respect to a direction of airflow.

14. The fin of the heat exchanger according to claim 12, wherein the condensed water guide protrudes a predetermined height.

15. The fin of the heat exchanger according to claim 14, wherein the height is between 0.3 mm and 0.6 mm.

16. The fin of the heat exchanger according to claim 12, wherein the condensed water guide is depressed by a predetermined depth.

17. The fin of the heat exchanger according to claim 12, wherein the condensed water guide has a substantially triangular or semicircular sectional shape.

18. The fin of the heat exchanger according to claim 12, wherein the condensed water guide extends vertically.

19. The fin of the heat exchanger according to claim 12, wherein the tube insert holes are arranged in two or more rows with respect to a direction of airflow, and the condensed water guide is formed between at least a front tube insert hole and a rear tube insert hole.

20. A fin of a heat exchanger comprising:

a plurality of tube insert holes formed in two or more rows at a front and a rear with respect to an airflow direction; and

a first and a second condensed water guide for guiding a drainage of condensed water generated during a heat exchange process between air and refrigerant in the tube, wherein

the first condensed water guide is formed at a rear of a center of a front tube insert hole with respect to the airflow direction, and

the second condensed water guide is formed at a rear of center of a rear tube insert hole with respect to the airflow direction.