The present application claims priority under 35 U.S.C. 119 and 35 U.S.C. 365 to Korean Patent Application No. 10-2012-0084515 filed on Aug. 1, 2012, which is hereby incorporated by reference in its entirety.
The present disclosure relates to a heat exchanger.
Heat exchangers are components that constitute a refrigeration cycle. Also, heat exchangers are configured to allow a refrigerant to flow therein. Heat exchangers may cool or heat air through heat exchange with the air. Such a heat exchanger may be used in a freezing device for an air conditioner, a refrigerator, or the like. Here, the heat exchanger may serve as a condenser or an evaporator according to whether a refrigerator is condensed or evaporated by the heat exchanger.
In detail, the heat exchanger includes a tube through which the refrigerant flows and a fin that is coupled to the tube to increase an area between the refrigerant within the tube and air, i.e., a heat exchange area. A plurality of through holes may be defined in the fin so that the tube is inserted into the through holes.
The fin may be provided in plurality. The plurality of fins may be stacked along an extending direction of the tube. A predetermined space may be defined between the stacked fins. Thus, air may be heat-exchanged with the refrigerant of the tube while flowing into the predetermined space.
A structure for increasing the heat exchange area, i.e., a louver may be provided on the fin. The louver may be formed by cutting and bending a portion of the fin. The louver may be provided on a plurality of areas of the entire surface area of the fin except for the through hole. A distance (stacked distance) between the stacked fins may decrease by the louver.
In the heat exchanger according to the related art, when the heat exchanger is used as the evaporator in the outside having a low temperature, condensed water may be frozen and thus implanted to a surface of the fin. Particularly, in the case where the louver is provided on the fin, the space between the fins may be blocked by frost. That is, since a passage through which air flows is blocked, heat exchange efficiency may be deteriorated. Also, a time required for defrosting of the heat exchanger may increase.
Particularly, when the heat exchanger is used in an air conditioner, since a heating operation of the air conditioner is restricted while a defrosting process of the air conditioner is performed, heating performance of the air conditioner may be deteriorated.
Embodiments provide a heat exchanger having improved heat transfer performance and defrosting performance.
In one embodiment, a heat exchanger includes: a refrigerant tube through which a refrigerant flows; and a fin having a plurality of tube through holes in which the refrigerant tube is inserted, wherein the fin includes: a fin body; a plurality of louvers protruding from a surface of the fin body; a plane part defined between the plurality of louvers, the plane part having a flat surface; and a guide part disposed on at least one side of the plane part to guide a flow of air or discharge of defrosting water.
In another embodiment, a heat exchanger includes: a refrigerant tube through which a refrigerant flows; and a fin including a fin body having a tube through hole in which the refrigerant tube is inserted, wherein the fin includes: a plurality of first louvers disposed on one side with respect to a center of the tube through hole to protrude from the fin body; a plurality of second louvers disposed on an opposing side with respect to the center of the tube through hole to protrude from the fin body; a first plane part defined between each of the first louvers and each of the second louvers to define a flat surface; a second plane part between the plurality of first louvers or between the plurality of second louvers to define a flat surface; and a guide part disposed on the first plane part or the second plane part, the guide part having an inclined surface for guiding a flow of air or discharge of defrosting water.
The details of one or more embodiments are set forth in the accompanying drawings and the description below. Other features will be apparent from the description and drawings, and from the claims.
Reference will now be made in detail to the embodiments of the present disclosure, examples of which are illustrated in the accompanying drawings. The invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein; rather, that alternate embodiments included in other retrogressive inventions or falling within the spirit and scope of the present disclosure will fully convey the concept of the invention to those skilled in the art.
Referring to
Each of the first and second heat exchange parts 20 and 30 includes a refrigerant tube 50 and a fin 100. The refrigerant tube 50 may be a tube for guiding a flow of a refrigerant. The refrigerant tube 50 may be formed of a metal such as aluminum or copper.
Also, the refrigerant tube 50 may be provided in plurality. The plurality of refrigerant tubes 50 may be vertically stacked on each other. Also, the plurality of refrigerant tubes 50 may be connected to each other by a return band 60. A refrigerant flowing in one direction through one refrigerant tube 50 of the plurality of refrigerant tubes 50 may be switched in flow in the other direction by passing through the return band 60 to flow into the other refrigerant tube 50.
The fin 100 may be fitted into the outside of the refrigerant tube 50 to increase a heat exchange area between the refrigerant tube 50 and air. Hereinafter, a fin 100 will be described with reference to the accompanying drawings.
Referring to
The plurality of tube through holes 110 are spaced apart from each other and arranged in a longitudinal direction (or length direction) of the fin 100. For convenience of description, a center of the tube through hole 110 defined in the uppermost side in
The plurality of flow guides 140 and 150 include a first flow guide 140 and a second flow guide 150 which are respectively disposed on one side and the other side of each of the centers C1, C2, and C3. The first and second flow guides 140 and 150 may be disposed to face each other on sides opposite to each other with respect to each of the centers C1, C2, and C3.
For example, as shown in
The first flow guide 140 may be provided in plurality. The plurality of first flow guides 140 are spaced apart from each other in a longitudinal direction of the fin 100. The first flow guides 140 are disposed on left upper and lower sides of the one tube through hole 110. For example, the first flow guides 140 may be disposed on left upper and lower sides of the tube through hole 110 having the center C2.
That is to say, when virtual horizontal and vertical lines passing through the center C2 by using the center C2 as the origin are respectively defined as an X-axis and a Y-axis, the first flow guides 140 may be disposed on a second quadrant and a fourth quadrant, respectively. Also, a lower end of the first flow guide 140 disposed on the second quadrant and an upper end of the first flow guide disposed on the fourth quadrant are spaced a predetermined distance D1 from each other.
Each of the first flow guides 140 may have a polygonal shape. For example, as shown in
When considering that an air flow F (see
The second flow guide 150 is symmetrical to the first flow guide 140 with respect to a virtual central line of the longitudinal direction of the fin 100. Here, the virtual central line of the longitudinal direction (hereinafter, referred to as a longitudinal central line) of the fin 100 may be understood as a virtual line connecting the centers C1, C2, and C3 to each other.
A second front end 151 is disposed on a left end of the second flow guide 150, and a second rear end 156 is disposed on a right end of the second flow guide 150.
The second front end 151 is disposed at a position symmetrical to that of the first front end 141 with respect to the longitudinal central line. The second rear end 156 is disposed at a position symmetrical to that of the first rear end 146 with respect to the longitudinal central line. Thus, the second rear end 156 and the right end of the fin 100 are spaced a predetermined distance D3 from each other. The distances D2 and D3 may be the same.
The first flow guide 140 includes a first louver 142 including a portion that protrudes from one surface or the other surface of the fin 100. Here, the one surface may be a top surface of the fin 100 shown in
At least one portion of the fin 100 may be cut and then bent in one and the other directions of the fin 100 to manufacture the first louver 142. The first louver 142 may increase a contact area between air and the fin 100. Here, the one direction may be a front side of the fin 100, and the other direction may be a rear side of the fin 100. The first louver 142 may be provided in plurality. The plurality of first louvers 142 may be disposed in the longitudinal direction of the fin 100.
Air may flow along the first louver 142 while passing through a side of the fin 100. For example, the air may flow from the one surface toward the other surface or from the other surface toward the one surface along the first louver 142.
The second flow guide 150 includes a second louver 152. The second louver 152 may have a shape similar to that of the first louver 142. Also, the second louver 152 may be provided in plurality. The plurality of second louvers 142 are spaced apart from each other in the longitudinal direction of the fin 100. Also, the second louver 152 is symmetrical to the first louver 142 with respect to the longitudinal central line of the fin 100.
The fin 100 includes a first plane part 121 extending in a transverse direction (or a width direction) of the fin 100 to define a flat surface and a second plane part 131 extending in the longitudinal direction (or a length direction) of the fin 100 to define a flat surface. The first and second plane parts 121 and 131 may be different from the first and second louver 142 or the second louver 153 in that each of the first and second plane parts 121 and 131 has a smooth surface.
The first plane part 121 is disposed between the plurality of tube through holes 110. In other words, the first plane part 121 may be disposed between the center C1 of the one tube through hole 110 and the center C2 of the other tube through hole 110.
The first plane part 121 may extend from the left end to the right end of the fin 100. Here, the extending direction of the first plane part 121 may correspond or parallel to the flow direction of the air passing through the plurality of fins 100 (see F1 of
The first plane part 121 is disposed in a space between the plurality of first louvers 142. Also, the first plane part 121 may be disposed in a space between the plurality of second louvers 152. That is, the first and second louvers 142 and 152 may not be provided on the entire area of the fin 100. Also, the first louvers 142 may be partitioned by the first plane part 121, and the second louvers 152 may be partitioned by the first plane part 121.
Referring to
Since the first plane part 121 is defined on a surface of the fin 100, the distance between the stacked fins 100 may increase. Thus, air may sufficiently flow through the increased space to delay implantation of frost.
The second plane part 131 is disposed between the plurality of tube through holes 110. In other words, the second plane part 131 may be disposed between the center C1 of the one tube through hole 110 and the center C2 of the other tube through hole 110.
The second plane part 131 may extend from an outer surface of the one tube through hole 110 to an outer surface of the other tube through hole 110. Here, the extending direction of the second plane part 131 may correspond to a direction in which defrosting water is discharged during the defrosting due to the gravity. Also, the second plane part 131 may be understood as a plane connecting the one tube through hole 110 to the other tube through hole 110.
For example, the second plane part 131 may extend in a direct downward direction.
The second plane part 131 may extend longitudinally along a space between the first louver 141 and the second louver 152. Thus, the first and second louvers 142 and 152 may be partitioned by the first plane part 121.
Referring to
Here, the transverse width L2 may be decided to one value less than a distance R from one end (e.g., a left end of
Since the second plane part 131 is defined on the surface of the fin 100, the defrosting water generated during the defrosting may be quickly discharged downward to reduce a defrosting time, thereby improving operation efficiency of the heat exchanger and efficiency of a heating operation of the air conditioner including the heat exchanger.
Each of the first and second plane parts 121 and 131 may define at least one portion of one surface of the fin body 101. Also, the first and second plane parts 121 and 131 are disposed crossing each other to share a predetermined area thereof. In detail, as shown in
Also, the first and second plane parts 121 and 131 may cross each other at a predetermined angle. The predetermined angle may be decided to one of angles greater than 0 degree and less than 90 degrees.
For example, the first and second plane parts 121 and 131 may vertically cross each other. Also, centers of the first and second plane parts 121 and 131 may cross each other to form a cross shape.
Referring to
Each of the fins 100 includes the first and second louvers 142 and 152 which are partitioned by the second plane part 131. Air may be introduced from one end of the fin 100 to pass through the first louver 141, the second plane part 131, and the second louver 152 (F1). Also, as described above, at least one portion of the air may flows from the one end of the fin 100 toward the other end along the first plane part 121.
The first and second louvers 142 and 152 may protrude from one surface of the fin body 101 to the other surface to inclinedly extend at a set angle θ with respect to the fin body 101. The set angle θ may be called a “louver angle”. As described above, the first and second louvers 142 and 152 may have the same shape as each other.
Also, a horizontal distance (a longitudinal distance in
To delay the implantation of the frost in the heat exchanger 10, the fin distance h may be greater than a predetermined value. Here, if the fin distance h is too large, heat transfer performance through the fins 100 may be deteriorated. Thus, the fin distance h should be set within an adequate range. The selection of an adequate value with respect to the fin distance h will be described with reference to
Referring to
The fins 100 constituting the heat exchanger 10 include a first fin 100a and a second fin 100b disposed on a side of the first fin 100a. The first and second fins 100a and 100b may extend longitudinally to overlap each other. Descriptions with respect to a constitution of each of the first and second fins 100a and 100b will be derived from those with respect to the constitution of the fins of
However, as shown in
In detail, the first fin 100a includes a plurality of tube through holes 110a through which the refrigerant tube 50 passes and first and second louvers 142 and 152 which are disposed between the plurality of tube through holes 110a. Also, a first plane part 121 may extend transversely to partition the plurality of first louvers 142 and the plurality of second louvers 152.
The second fin 100b includes a plurality of tube through holes 110b through which the refrigerant tube 50 passes and first and second louvers 142 and 152 which are disposed between the plurality of tube through holes 110b. Also, a first plane part 121 may extend transversely to partition the plurality of first louvers 142 and the plurality of second louvers 152.
The tube through hole 110a of the first fin 100a and the tube through hole 110b of the second fin 110b are defined at heights different from each other. That is to say, a center C4 of the tube through hole 100a and a center C5 of the tube through hole 110b are defined at heights different from each other. That is, the centers C4 and C5 may have a predetermined spaced height K therebetween.
Also, a spaced portion (or area) between the plurality of first louvers 142 is disposed on a side of the first plane part 121 of the first fin 100a. Here, the spaced portion may be a portion of the fin body 101 as a portion corresponding to a spaced distance D1 in
Thus, air F1 introduced into a side of the first fin 100a passes through the first plane part 121 of the first fin 100a to flow into the tube through hole 110b of the second fin 100b via the spaced portion. That is, since high speed air flowing along the first plane part 121 of the first fin 100a disposed in a first row directly acts on the refrigerant tube disposed in a second row, a heat exchange amount of the refrigerant tube 50 disposed in the second row may increase.
Referring to
As described above, as the ratio L1/S increases, an area of the first plane part 121 decreases. Thus, a heat exchange amount may be reduced somewhat. In
On the other hand, as the ratio L1/S increases, an air flow amount between the stacked fins increases. Thus, an amount of frost implanted on the fins 100 may be reduced. Thus, the continuous operation time of the heat exchanger 20 till a time point at which the defrosting operation is required may increase. In
That is, as the ratio L1/S increases, the heat exchange amount and the operation time have different distributions. Thus, a range of the ratio L1/S that is capable of adequately securing the two performances is proposed. As shown in
Referring to
As described above, as the ratio L2/S increases, an area of the second plane part 131 increases. Thus, the defrosting operation may be quickly performed. In
However, since an area of the first or second louver 142 or 152 decreases as the ratio L2/R increases, the heat exchange amount of the fin 100 may be relatively reduced. Thus, the ratio L2/R may be restricted to a value less than a predetermined value within a range in which the defrosting operation is quickly performed.
Thus, in
Referring to
As described above, as the distance h increases, the distance between the fins increases. Thus, the heat exchange amount may be reduced somewhat. In
On the other hand, as the distance h increases, an air flow amount between the stacked fins increases. Thus, an amount of frost implanted on the fins 100 may be relatively reduced. Thus, the continuous operation time of the heat exchanger 20 till a time point at which the defrosting operation is required may increase. In
That is, as the distance h increases, the heat exchange amount and the operation time have different distributions. Thus, a range of the distance h that is capable of adequately securing the two performances is proposed. As shown in
Also, when the fin distance h is in the above-described range, an FPI, a pitch P, and a louver angle θ may have a range value as follows. Here, the FPI (fin per inch) may be understood as the number (stacked number) of heat exchange fins per 1 inch.
The range value may be expressed as follows: 12≦FPI≦15, 0.8≦P≦1.2 mm, 27°≦θ≦45°.
Referring to
Each of the first flow guides 140 includes a first front part 141 adjacent to one end of the fin 100 and a first rear end 146 adjacent to the longitudinal central line. Also, each of the second flow guides 150 includes a second rear end 156 adjacent to the other end of the fin 100 and a second front end 151 adjacent to the longitudinal central line.
A first plane part 121 partitioning the first flow guides 140 is disposed between the plurality of first flow guides 140. The first plane part 121 may have different widths. That is, a boundary surface of the first plane part 121 may inclinedly extend. Thus, a width a1 at one point of the first plane part 121 may be greater or less than that a2 at the other point.
Here, the width a1 may correspond to a distance between the first front part 141 of one first flow guide 140 and the first front part 141 of the other first flow guide 140, and the width a2 may correspond to a distance between the first rear end 146 of one first flow guide 140 and the first rear end 146 of the other first flow guide 140.
As described above, when the first plane part 121 has different widths, for example, when a1>a2 is satisfied, a flow rate of air may increase to increase an air flow amount. On the other hand, when a1<a2 is satisfied, a heat exchange area between air and the first plane part 121 may increase to increase a heat exchange amount.
A second plane part 131 is disposed on the first flow guide 140 and the second flow guide 150. The second plane part 131 may have different widths. That is, a boundary surface of the second plane part 131 may inclinedly extend. Thus, a width b1 at one point of the second plane part 131 may be greater or less than that b2 at the other point.
Here, the width b1 may correspond to a distance between an upper portion of the first rear end 146 of the first flow guide 140 and an upper portion of the second front end 151 of the second flow guide 150, and the width b2 may correspond to a distance between a lower portion of the first rear end 146 of the first flow guide 140 and a lower portion of the second front part 146 of the second flow guide 150.
As described above, when the second plane part 131 has width different from each other, for example, when b1>b2 is satisfied, defrosting water is collected while dropping down to increase a discharge rate of the defrosting water. On the other hand, when b1<b2 is satisfied, a flow area of the defrosting water may increase.
Hereinafter, third to sixth embodiments will be described. These embodiments are different the first embodiment in that a “guide part” for improving heat transfer performance and defrosting performance is provided in the constitution of the fin according to the first embodiment. Thus, different points will be mainly described, and descriptions and reference numerals with respect to the same part as the first embodiment are derived from those of the first embodiment.
Referring to
The guide part 250 protrudes from the second plane part 131 to longitudinally extend from one tube through hole 110 toward the other tube through hole 110. For example, the guide part 250 may be disposed to cover at least one portion of the second plane part 131.
In detail, the guide part 250 includes a first inclined surface 251 inclinedly protruding from a fin body 101 in one direction, a second inclined surface 252 inclinedly protruding from the fin body 101 in the other direction, and a tip part 253 connecting the first inclined surface 251 to the second inclined surface 252.
The tip part 253 protrudes from one surface of the fin body up to the uppermost position of the fin body 101. Each of the first and second inclined surfaces 251 and 252 inclinedly extend from one surface of the fin body 101 toward the tip part 253. At least one of the first inclined surface 251, the second inclined surface 252, and the tip part 253 extends in a longitudinal direction.
On the other hand, the first inclined surface 251 inclinedly extends upward from the fin body 101, and the second inclined surface 252 inclinedly extends downward toward the fin body 101. The tip part 253 defines a boundary between the first inclined surface 251 and the second inclined surface 252.
Each of the first inclined surface 251, the second inclined surface 252, and the tip part 253 may be provided in plurality. Here, the plurality of each of the first inclined surface 251, the second inclined surface 252, and the tip part 253 may be alternately disposed.
Also, a height at which the tip part 253 protrudes from the one surface of the fin body 101 may be greater than that at which a first or second louver 142 or 152 protrudes from one surface of the fin body 101.
Thus, since defrosting water generated during an defrosting operation of a heat exchanger 10 may be easily discharged downward along the first and second inclined surfaces 251 and 252, a defrosting time may be reduced, and thus, an operation time of the heat exchanger 10 may increase.
Also, since a heat exchange area between air and the fin 100 increases by the guide part 250, heat transfer performance of the heat exchanger 10 may be improved somewhat.
Referring to
The guide part 350 includes a central portion 350a having the same surface as the first plane part 121 and a plurality of cutoff portions 352 and 353 that are defined by cutting at least portions of the fin body 101. The central portion 350a may be understood as at least one portion of the first or second plane part 121 or 131.
The plurality of cutoff portions 352 and 353 include first and second cutoff portions 352 and 353 which are respectively disposed on upper and lower portions of the guide part.
The guide part 350 includes a first end 351a defining an upper end of the guide part 350 and a first inclined surface 355 inclinedly extending from the first end 351a toward the first cutoff portion 352. Also, the guide part 350 includes a second end 351b defining a lower end of the guide part 350 and a second inclined surface 356 inclinedly extending from the second end 351b toward the second cutoff portion 353. In detail, the first inclined surface 355 may inclinedly extend from the first end 351a in one direction (a rear direction in
In summary, the guide part 350 may include the inclined surfaces inclinedly extending in the one direction by cutting at least portions of the plane parts 121 and 131. Due to the constitutions of the cutoff portion and the inclined surface, it may be understood that at least one slit is provided on the fin 300. According to the constitutions of the fin according to the current embodiment, the heat exchange area may increase while air flows along the fin 100 to improve heat exchange efficiency.
Although the guide part 350 longitudinally extends on the second plane part 131 in the drawings, the present disclosures is not limited thereto. For example, the guide part 350 may transversely extend on the first plane part 121.
Referring to
In detail, the guide part 450 includes a third louver 452 that is similar to the first or second louver 142 or 152 described in the first embodiment. At least one portion of the first plane part 121 is cut and then bent in one direction (e.g., a front direction) and the other direction (e.g., a rear direction) of the fin 10 to manufacture the third louver 452.
Since the third louver 452 is provided on the first plane part 121, a heat exchange area between air and the fin 100 may increase.
Although the third louver 452 is provided on the first plane part 121 in
Referring to
The guide part 550 includes a first inclined surface 551 protruding from one surface of the fin 200 in one direction, a second inclined surface 552 protruding from the one surface of the fin 500 in the other direction, and a tip part 553 connecting the first inclined surface 551 to the second inclined surface 552.
Each of the first inclined surface 551, the second inclined surface 552, and the tip part 553 may be provided in plurality. Here, the plurality of each of the first inclined surface 251, the second inclined surface 252, and the tip part 253 may be alternately disposed.
The guide part 550 may transversely extend along the first plane part 121. That is, the guide part 550 according to the current embodiment may be understood that the guide part 250 of
Due the constitution of the guide 550, defrosting water may be easily discharged, and a contact area, i.e., a heat exchange area between air and the fin 500 may increase.
According to the embodiments, since the plane part for guiding the air flow is provided on the fin, the frost implantation on the fin may be delayed. Also, the air flow may be improved to increase an amount of air passing through the heat exchanger and reduce a loss of a pressure applied to the heat exchanger.
Also, the plane part for guiding the discharge of the condensed water may be provided on the fin to reduce the defrosting time. Thus, when the heat exchanger is used in the air conditioner, the heating time and performance of the air conditioner may be improved.
Also, in a case where the assembly of the refrigerant tube and the fin is arranged in two rows, since air directly contacts the refrigerant tube disposed in the rear row along the plane part disposed on in the front row, heat transfer performance in the rear row may be improved.
Also, each of the plane parts disposed on the fin may be provided to have an optimum size to improve the heat exchange amount of the heat exchanger and increase an operation time of the heat exchanger until the frost implantation occurs.
Also, since the guide part for guiding the flows of the air and defrosting water is provided on the plane part of the fin, the heat transfer performance and defrosting performance of the heat exchanger may be improved.
Although embodiments have been described with reference to a number of illustrative embodiments thereof, it should be understood that numerous other modifications and embodiments can be devised by those skilled in the art that will fall within the spirit and scope of the principles of this disclosure. More particularly, various variations and modifications are possible in the component parts and/or arrangements of the subject combination arrangement within the scope of the disclosure, the drawings and the appended claims. In addition to variations and modifications in the component parts and/or arrangements, alternative uses will also be apparent to those skilled in the art.
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