U.S. patent application number 14/244282 was filed with the patent office on 2014-12-18 for heat exchanger and outdoor unit for air-conditioner having the same.
This patent application is currently assigned to SAMSUNG ELECTRONICS CO., LTD.. The applicant listed for this patent is SAMSUNG ELECTRONICS CO., LTD.. Invention is credited to Yong Hwa Choi, Hayase Gaku, Sung Hun Hong, Choong Hyo Jang, Seung Hoon Kal, Hong Suk KIM, Myong Jong Kwon, Seung Jin Oh.
Application Number | 20140366568 14/244282 |
Document ID | / |
Family ID | 50819577 |
Filed Date | 2014-12-18 |
United States Patent
Application |
20140366568 |
Kind Code |
A1 |
KIM; Hong Suk ; et
al. |
December 18, 2014 |
HEAT EXCHANGER AND OUTDOOR UNIT FOR AIR-CONDITIONER HAVING THE
SAME
Abstract
A heat exchanger includes a refrigerant pipe through which a
refrigerant flows, and a plurality of fins coupled to an outer
circumference surface of the refrigerant pipe, wherein each fin
includes a first region disposed upstream with respect to an air
flow direction, and a second region which forms a boundary with the
first region and is disposed downstream with respect to the air
flow direction, and wherein the first region and the second region
have different surface energies in order to prevent formation of
condensation water on the fin.
Inventors: |
KIM; Hong Suk; (Seoul,
KR) ; Kal; Seung Hoon; (Anyang-si, KR) ; Kwon;
Myong Jong; (Suwon-si, KR) ; Oh; Seung Jin;
(Seoul, KR) ; Jang; Choong Hyo; (Daejeon, KR)
; Choi; Yong Hwa; (Hwaseong-si, KR) ; Gaku;
Hayase; (Seongnam-si, KR) ; Hong; Sung Hun;
(Hwaseong-si, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SAMSUNG ELECTRONICS CO., LTD. |
Suwon-si |
|
KR |
|
|
Assignee: |
SAMSUNG ELECTRONICS CO.,
LTD.
Suwon-si
KR
|
Family ID: |
50819577 |
Appl. No.: |
14/244282 |
Filed: |
April 3, 2014 |
Current U.S.
Class: |
62/272 |
Current CPC
Class: |
F28F 1/12 20130101; F28D
2021/0068 20130101; F28D 1/0477 20130101; F25B 1/005 20130101; F24F
1/18 20130101; F28F 1/32 20130101; F28F 17/005 20130101; F24F 1/14
20130101; F28F 2245/02 20130101; F28F 2245/04 20130101; F24F 13/22
20130101; F28D 2021/0071 20130101; F25D 21/04 20130101; F24F
2013/221 20130101 |
Class at
Publication: |
62/272 |
International
Class: |
F25D 21/04 20060101
F25D021/04; F25B 1/00 20060101 F25B001/00; F28F 1/12 20060101
F28F001/12 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 13, 2013 |
KR |
10-2013-0068035 |
Claims
1. A heat exchanger comprising: a refrigerant pipe through which a
refrigerant flows; and a plurality of fins coupled to an outer
circumference surface of the refrigerant pipe, wherein each fin
comprises a first region disposed upstream with respect to an air
flow direction; and a second region which forms a boundary with the
first region and is disposed downstream with respect to the air
flow direction, and wherein the first region and the second region
have different surface energies in order to prevent formation of
condensation water on the fin.
2. The heat exchanger according to claim 1, wherein the boundary is
formed such that a width of the first region in a longitudinal
direction of the fin is uniform.
3. The heat exchanger according to claim 1, wherein the first
region has a width of about 5 mm or less.
4. The heat exchanger according to claim 1, wherein the boundary is
formed such that the width of the first region in the longitudinal
direction of the fin is non-uniform.
5. The heat exchanger according to claim 1, wherein the first
region is coated with a hydrophilic agent having a high surface
energy so as to facilitate discharge of condensation water formed
in the first region.
6. The heat exchanger according to claim 5, wherein the hydrophilic
agent comprises at least one of a carboxyl group (--COOH), an
alcohol group (--OH), an amine group (--NH.sub.2), a sulfonic acid
group (--SO.sub.3H) and a urea group (--NHCONH.sub.2).
7. The heat exchanger according to claim 1, wherein the first
region is coated with a hydrophobic agent having a low surface
energy so as to prevent formation of condensation water in the
first region.
8. The heat exchanger according to claim 7, wherein the hydrophobic
agent comprises at least one of an inorganic nanopowder and a
fluorine compound.
9. The heat exchanger according to claim 1, wherein, when the first
region is coated with a hydrophilic agent having a high surface
energy, the second region is coated with a hydrophobic agent or is
uncoated.
10. The heat exchanger according to claim 1, wherein, when the
first region is coated with a hydrophobic agent having a low
surface energy, the second region is coated with a hydrophilic
agent or is uncoated.
11. The heat exchanger according to claim 1, wherein, when the
first region is uncoated, the second region is coated with a
hydrophilic agent or a hydrophobic agent.
12. The heat exchanger according to claim 1, wherein one of the
first region and the second region is covered with a mask, the
entire surface of the fin is coated with a hydrophobic agent, the
mask is removed and the region covered with the mask is coated with
a hydrophilic agent.
13. The heat exchanger according to claim 1, wherein one of the
first region and the second region is covered with a mask, the
entire surface of the fin is coated with a hydrophilic agent, the
mask is removed and the region covered with the mask is coated with
a hydrophobic agent.
14. The heat exchanger according to claim 1, wherein the first
region and the second region are coated by at least one of
dipcoating, spray coating and vacuum evaporation such that a
difference in surface energy between the first region and the
second region is present.
15. The heat exchanger according to claim 1, wherein the first
region or the second region is coated with a hydrophilic agent and
the uncoated region is coated with a hydrophobic agent by
dipcoating.
16. A heat exchanger comprising: a refrigerant pipe having a flow
channel through which a refrigerant flows; and a plurality of fins
coupled to an outer circumference surface of the refrigerant pipe,
wherein each fin comprises a first region which is disposed
upstream with respect to a high-temperature air flow direction and
has a constant width; and a second region which contacts air
passing through the first region and forms a boundary with the
first region, wherein both surfaces of the first region are coated
with a hydrophobic agent having a low surface energy to prevent
formation of condensation water in the first region upon
heat-exchange between the high-temperature air flowing in the first
region and the refrigerant flowing in the refrigerant pipe, and
both surfaces of the second region are coated with a hydrophilic
agent having a high surface energy to facilitate discharge of
condensation water formed in the second region upon heat-exchange
between the high-temperature air passing through the first region
and the refrigerant flowing in the refrigerant pipe.
17. The heat exchanger according to claim 16, wherein the
refrigerant pipe is bent in a zigzag form, and the second region
has a plurality of through holes formed by which the refrigerant
pipe passes through the fin in a zigzag form.
18. The heat exchanger according to claim 16, wherein the
hydrophilic agent comprises at least one of a carboxyl group
(--COOH), an alcohol group (--OH), an amine group (--NH.sub.2), a
sulfonic acid group (--SO.sub.3H) and a urea group
(--NHCONH.sub.2), and the hydrophobic agent comprises at least one
of an inorganic nanopowder and a fluorine compound.
19. The heat exchanger according to claim 16, wherein both surfaces
of the first region are covered with a mask, the entire surface of
the fin is coated with a hydrophilic agent, the mask is removed and
the region covered with the mask is coated with a hydrophobic
agent.
20. An outdoor unit for air-conditioners comprising: a body; a
compression unit disposed in the body, the compression unit
compressing a refrigerant; and a heat exchanger to heat-exchange
the refrigerant compressed by the compression unit with outdoor
air, wherein the heat exchanger comprises a refrigerant pipe
through which a refrigerant flows; and a plurality of fins adhered
to an outer circumference surface of the refrigerant pipe, wherein
each fin comprises a first region disposed upstream with respect to
an air flow direction; and a second region forming a boundary with
the first region and disposed downstream with respect to the air
flow direction, wherein the first region and the second region are
coated such that the first and second regions have different
surface energies in order to prevent formation of condensation
water on the fin.
21. The outdoor unit for air-conditioners according to claim 20,
wherein the first region has a constant width in a longitudinal
direction of the fin and is coated with a hydrophobic agent which
prevents formation of condensation water due to low surface energy.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of Korean Patent
Application No. 10-2013-0068035, filed on Jun. 13, 2013, in the
Korean Intellectual Property Office, the disclosure of which is
incorporated herein by reference.
BACKGROUND
[0002] 1. Field
[0003] Embodiments of the present disclosure relate to a heat
exchanger which has a structure improved to enhance efficiency
thereof and an outdoor unit for air-conditioners having the
same.
[0004] 2. Description of the Related Art
[0005] A heat exchanger is mounted and used in an apparatus using
refrigeration cycles such as air-conditioners or refrigerators,
which includes a plurality of heat exchanger fins and a plurality
of refrigerant pipes which are mounted such that they guide a
refrigerant and pass through the heat exchanger fins. The heat
exchanger fins increase a contact area with outside air flowing in
the heat exchanger and thereby improve heat exchange efficiency
between refrigerant flowing in the refrigerant pipes and outside
air.
[0006] In general, heat exchange efficiency increases as a gap
between heat exchanger fins decreases and a contact area between
the heat exchanger fins and the outside air increases.
[0007] In a case in which an evaporator is used as the heat
exchanger, a surface of the evaporator is maintained at a low
temperature due to circulation of cold refrigerant, while inflowing
air has a relatively high temperature. Accordingly, inflowing air
containing moisture contacts the heat exchanger fins of the
evaporator maintained at a low temperature and a dew point of air
which contacts the heat exchanger fins is dropped, dew is formed on
the surface of the heat exchanger fins and accumulated dew forms
condensation water.
[0008] In addition, when the air flowing in the heat exchanger has
a high temperature and a high humidity, air passing through the
heat exchanger while contacting the fins is heat-exchanged with the
refrigerant and is thus approximately saturated, while air passing
through the fins while not contacting the fins maintains a
relatively high temperature and high humidity. As such, air having
different properties is mixed and fog is thus formed on the fins.
In particular, fog is readily formed in an area of the heat
exchanger where air having a low velocity and a high temperature
difference is mixed.
[0009] In addition, the condensation water formed on the fins is
cooled and ice is thus formed.
[0010] In addition, frosting may occur on the fins. Frosting is a
phenomenon in which, when wet air contacts a cooling side
maintained at a low temperature of 0.degree. or below, a porous
frost layer is formed on the cooling side. That is, the frosting
phenomenon may occur on the fin surface when high-temperature
high-humidity air flowing in the heat exchanger contacts the fins
maintained at a low temperature due to the refrigerant.
[0011] As such, condensation water formed on the heat exchanger
fins of the evaporator is formed between the heat exchanger fins of
the heat exchanger, or creates a bridge between the heat exchanger
fins. The condensation water, fog, ice and the like present between
the heat exchanger fins interrupt air flow between the heat
exchanger fins and thus hinder smooth heat exchange.
[0012] In addition, condensation water causes corrosion of a metal
material constituting the heat exchanger fins, produces white
powder oxides and causes microorganism propagation.
[0013] In addition, a frost layer is grown due to frosting
phenomenon, disadvantageously causing an increase in thermal
resistance of the heat exchanger and decreasing a flow rate of air
passing through the heat exchanger due to flow channel closure.
SUMMARY
[0014] Therefore, it is an aspect of the present disclosure to
provide a heat exchanger which has an improved structure so as to
remove condensation water and a frost layer derived from a frosting
phenomenon and thereby enhance heat exchange efficiency.
[0015] Additional aspects of the disclosure will be set forth in
part in the description which follows and, in part, will be
apparent from the description, or may be learned by practice of the
disclosure.
[0016] In accordance with one aspect of the present disclosure, a
heat exchanger includes a refrigerant pipe through which a
refrigerant flows, and a plurality of fins coupled to an outer
circumference surface of the refrigerant pipe, wherein each fin
includes a first region disposed upstream with respect to an air
flow direction, and a second region which forms a boundary with the
first region and is disposed downstream with respect to the air
flow direction, and wherein the first region and the second region
have different surface energies in order to prevent formation of
condensation water on the fin.
[0017] The boundary may be formed such that a width of the first
region in a longitudinal direction of the fin is uniform.
[0018] The first region may have a width of about 5 mm or less.
[0019] The boundary may be formed such that the width of the first
region in the longitudinal direction of the fin is non-uniform.
[0020] The first region may be coated with a hydrophilic agent
having a high surface energy so as to facilitate discharge of
condensation water formed in the first region.
[0021] The hydrophilic agent may include at least one of a carboxyl
group (--COOH), an alcohol group (--OH), an amine group
(--NH.sub.2), a sulfonic acid group (--SO.sub.3H) and a urea group
(--NHCONH.sub.2).
[0022] The first region may be coated with a hydrophobic agent
having a low surface energy so as to prevent formation of
condensation water in the first region.
[0023] The hydrophobic agent may include at least one of an
inorganic nanopowder and a fluorine compound.
[0024] When the first region is coated with a hydrophilic agent
having a high surface energy, the second region may be coated with
a hydrophobic agent or be uncoated.
[0025] When the first region is coated with a hydrophobic agent
having a low surface energy, the second region may be coated with a
hydrophilic agent or be uncoated.
[0026] When the first region is uncoated, the second region may be
coated with a hydrophilic agent or a hydrophobic agent.
[0027] One of the first region and the second region may be covered
with a mask, the entire surface of the fin may be coated with a
hydrophobic agent, the mask may be removed and the region covered
with the mask may be coated with a hydrophilic agent.
[0028] In addition, one of the first region and the second region
may be covered with a mask, the entire surface of the fin may be
coated with a hydrophilic agent, the mask may be removed and the
region covered with the mask may be coated with a hydrophobic
agent.
[0029] The first region or the second region may be coated with a
hydrophilic agent and the uncoated region is coated with a
hydrophobic agent by dipcoating.
[0030] The first region and the second region may be coated by at
least one of dip coating, spray coating and vacuum evaporation such
that a difference in surface energy between the first region and
the second region is present.
[0031] In accordance with another aspect of the present disclosure,
a heat exchanger includes a refrigerant pipe having a flow channel
through which a refrigerant flows, and a plurality of fins coupled
to an outer circumference surface of the refrigerant pipe, wherein
each fin includes a first region which is disposed upstream with
respect to a high-temperature air flow direction and has a constant
width, and a second region which contacts air passing through the
first region and forms a boundary with the first region, wherein
both surfaces of the first region are coated with a hydrophobic
agent having a low surface energy to prevent formation of
condensation water in the first region upon heat-exchange between
the high-temperature air flowing in the first region and the
refrigerant flowing in the refrigerant pipe, and both surfaces of
the second region are coated with a hydrophilic agent having a high
surface energy to facilitate discharge of condensation water formed
in the second region upon heat-exchange between the
high-temperature air passing through the first region and the
refrigerant flowing in the refrigerant pipe.
[0032] The refrigerant pipe may be bent in a zigzag form, and the
second region may have a plurality of through holes formed by which
the refrigerant pipe passes through the fin in a zigzag form.
[0033] The hydrophilic agent may include at least one of a carboxyl
group (--COOH), an alcohol group (--OH), an amine group
(--NH.sub.2), a sulfonic acid group (--SO.sub.3H) and a urea group
(--NHCONH.sub.2), and the hydrophobic agent may include at least
one of an inorganic nanopowder and a fluorine compound.
[0034] Both surfaces of the first region may be covered with a
mask, the entire surface of the fin may be coated with a
hydrophilic agent, the mask may be removed and the region covered
with the mask may be coated with a hydrophobic agent.
[0035] In accordance with another aspect of the present disclosure,
an outdoor unit for air-conditioners includes a body, a compression
unit disposed in the body, the compression unit compressing a
refrigerant, and a heat exchanger to heat-exchange the refrigerant
compressed by the compression unit with outdoor air, wherein the
heat exchanger includes a refrigerant pipe through which a
refrigerant flows, and a plurality of fins adhered to an outer
circumference surface of the refrigerant pipe, wherein each fin
includes a first region disposed upstream with respect to an air
flow direction, and a second region forming a boundary with the
first region and disposed downstream with respect to the air flow
direction, wherein the first region and the second region are
coated such that the first and second regions have different
surface energies in order to prevent formation of condensation
water on the fin.
[0036] The first region may have a constant width in a longitudinal
direction of the fin and may be coated with a hydrophobic agent
which prevents formation of condensation water due to low surface
energy.
BRIEF DESCRIPTION OF THE DRAWINGS
[0037] These and/or other aspects of the disclosure will become
apparent and more readily appreciated from the following
description of the embodiments, taken in conjunction with the
accompanying drawings of which:
[0038] FIG. 1 is a perspective view illustrating a configuration of
a heat exchanger according to an embodiment of the present
disclosure;
[0039] FIG. 2 is a view illustrating a fin provided in the heat
exchanger according to the present embodiment;
[0040] FIG. 3 is a view illustrating a contact angle of
condensation water formed on the fin provided in the heat exchanger
according to the present embodiment.
[0041] FIGS. 4A to 4D are views illustrating a boundary formed on
the fin provided in the heat exchanger according to the present
embodiment; and
[0042] FIG. 5 is a perspective view illustrating a schematic
structure of an outdoor unit for an air-conditioner including the
heat exchanger according to the present embodiment.
DETAILED DESCRIPTION
[0043] Hereinafter, preferred embodiments of the present disclosure
will be described with reference to the accompanying drawings.
[0044] FIG. 1 is a perspective view illustrating a configuration of
a heat exchanger according to an embodiment of the present
disclosure.
[0045] As shown in FIG. 1, the heat exchanger 10 includes a
refrigerant pipe 20 in which a refrigerant flows and a fin 30
coupled to an outer circumference surface of the refrigerant pipe
20.
[0046] The refrigerant pipe 20 has a hollow tubular shape, enabling
the fluid refrigerant to flow. The refrigerant pipe 20 is
preferably as long as possible to increase a heat exchange area
between the refrigerant flowing in the refrigerant pipe 20 and
outside air. However, if the refrigerant pipe 30 extends to a great
length in a single direction, spatial utilization efficiency is
poor. Accordingly, the refrigerant pipe 20 is bent in a direction
opposite to a direction in which the refrigerant pipe 20 extends
from both ends of the heat exchanger 10 and bending is repeated
several times, thereby efficiently increasing a heat exchange area
in a limited space.
[0047] As the refrigerant flowing in the refrigerant pipe 20, a
plurality of refrigerants including R-134a and R410A which are
mixtures of Freon having different properties are used.
[0048] The refrigerant is heat-exchanged with outside air while
undergoing phase change (compression) from a gas state to a liquid
state or is heat-exchanged with outside air while undergoing phase
change (expansion) from a liquid state to a gas state. When the
refrigerant is phase-changed from a gas state to a liquid state,
the heat exchanger 10 is used as a condenser and when the
refrigerant is phase-changed from a liquid state to a gas state,
the heat exchanger 10 is used as an evaporator.
[0049] The refrigerant is compressed or expanded and, at the same
time, emits heat to the outside or absorbs heat from the outside
when while passing through the refrigerant pipe 20. Upon
compression or expansion, the fin 30 is coupled to the refrigerant
pipe 20 so that the refrigerant efficiently emits or absorbs
heat.
[0050] A plurality of fins 30 including the fin 30 are laminated at
a constant distance in a direction in which the refrigerant pipe 20
extends.
[0051] The fin 30 is made of one of various metal materials
including aluminum having high thermal conductivity, and contacts
and is coupled to the outer circumference surface of the
refrigerant pipe 20 and thereby functions to increase a contact
area between the fin 30 and the refrigerant pipe 20.
[0052] As the gap between the fins 30 laminated becomes narrow, the
number of fins 30 disposed increases. However, as the gap is
excessively narrowed, as shown in FIG. 1, the gap acts as a
resistance to the air flowing in the heat exchanger 10 and may
cause pressure loss. Accordingly, it may be necessary to suitably
control the gap.
[0053] A louver (not shown) which is bent to form a predetermined
angle may be formed on the surface of the fin 30. The louver
increases a contact area in which the fin 30 contacts outside air
and thereby facilitates heat-exchange.
[0054] The surface of the fin 30 includes a first region 50 and a
second region 60.
[0055] The first region 50 may be formed upstream with respect to
an air flow direction and the second region 60 may form a boundary
80 with the first region 50 and be formed downstream with respect
to the air flow direction.
[0056] A material for the refrigerant pipe 20 and the fin 30
constituting the heat exchanger 10 may be aluminum, copper or the
like.
[0057] FIG. 2 shows a fin provided in the heat exchanger according
to the present embodiment, and FIG. 3 shows a contact angle of
condensation water formed on the fin provided in the heat exchanger
according to the present embodiment.
[0058] As shown in FIG. 2, the surface of the fin 30 may include
the first region 50 and the second region 60.
[0059] In addition, the second region 60 may be provided with a
plurality of through holes 40 which enable the refrigerant pipes 20
to pass through the fins 30 in a zigzag form.
[0060] In addition, the boundary 80 disposed between the first
region 50 and the second region 60 is formed such that a width of
the first region 50 in a longitudinal direction of the fin 30
[0061] uniform.
[0062] The boundary 80 may be formed at a position which enables
the first region 50 to have a width of 5 mm or less.
[0063] In addition, the boundary 80 may be formed such that a width
of the first region 50 in the longitudinal direction of the fin 30
is non-uniform.
[0064] The boundary 80 may have a linear shape.
[0065] The air flowing in the heat exchanger 10 sequentially passes
through the first region 50 and the second region 60 and then flows
outside of the heat exchanger 10.
[0066] The first region 50 and the second region 60 may be treated
so as to prevent formation of a condensation water 70 on the
surface of the fin 30 or facilitate discharge of the formed
condensation water 70.
[0067] The first region 50 and the second region 60 may have
different surface energies.
[0068] Each of the first region 50 and the second region 60 may be
coated with a hydrophilic agent or a hydrophobic agent or may be
uncoated.
[0069] Hydrophobicity is a property of an object in which
hemispheric drops are formed when a surface of the object is wet
with water. Hydrophilicity is a property of an object in which
hemispheric drops are not formed but are aggregated together and
widely spread when a surface of the object is wet with water.
[0070] Hydrophobic and hydrophilic substances have different
surface energies.
[0071] When a heterogeneous substance is placed on a liquid or
solid surface, the surface of the liquid or solid has a high energy
as compared to an inside of the liquid or solid, and an excessive
energy of the liquid or solid surface tends to contract a surface
at all times and this is referred to as surface energy.
[0072] That is, the fin 30 in a solid state has a predetermined
surface energy and has a property of drawing the condensation water
70 formed on the surface of the fin 30 toward the fin 30 as the
surface contraction property.
[0073] In general, when the fin 30 is coated with a hydrophobic
agent, the fin 30 has a low surface energy, and when the fin 30 is
coated with a hydrophilic agent, the fin 30 has a high surface
energy.
[0074] Accordingly, as shown in FIG. 3, when the fin 30 is coated
with a hydrophobic agent, the condensation water 70 formed on the
fin 30 has a large contact angle (regarding a liquid and a solid
which contact each other, an angle formed by the surface of the
liquid and the surface of the solid), and when the fin 30 is coated
with a hydrophilic agent, the condensation water 70 formed on the
fin 30 has a small contact angle.
[0075] When the contact angle between the fin 30 and the
condensation water contacts is 40 degrees or less, the fin 30 is
considered to be hydrophilic, and when the contact angle is 10
degrees or less, the fin 30 is considered to be super hydrophilic.
In addition, when the contact angle is 70 degrees or above and is
100 degrees or below, the fin 30 is considered to be hydrophobic,
and when the contact angle is 110 degrees or above and is 180
degrees or below, the fin 30 is considered to be super
hydrophobic.
[0076] In a case of non-coating, the contact angle between the fin
30 and the condensation water ranges from a hydrophilic value to a
hydrophobic value because a surface of the raw material of the fin
30 is used without any treatment.
[0077] Contact angle increases in order of hydrophilic coating,
non-coating and hydrophobic coating.
[0078] When the first region 50 is coated with a hydrophobic agent,
the second region 60 may be coated with a hydrophilic agent or be
uncoated.
[0079] When the first region 50 is coated with a hydrophilic agent,
the second region 60 may be coated with a hydrophobic agent or be
uncoated.
[0080] When the first region 50 is uncoated, the second region 60
may be coated with a hydrophilic agent, or be uncoated.
[0081] The first region 50 may be coated with a hydrophobic agent
and the second region 60 may be coated with a hydrophilic
agent.
[0082] Formation of the condensation water 70 in the first region
50 upon heat exchange between high-temperature air flowing in the
first region 50 and the refrigerant flowing in the refrigerant pipe
20 is prevented by coating the first region 50 with a hydrophobic
agent. Discharge of the condensation water 70 formed in the second
region 60 upon heat exchange between the high-temperature air
passing through the first region 50 and the refrigerant flowing in
the refrigerant pipe 20 is facilitated by coating the second region
60 with a hydrophilic agent.
[0083] In addition, although the condensation water 70 is formed in
the first region 50 coated with a hydrophobic agent, the
condensation water 70 formed in the first region 50 is transferred
together with the air flowing in the first region 50 to the second
region 60. Then, in the second region 60 coated with a hydrophilic
agent, the condensation water 70 formed in the first region 50
joins with the condensation water 70 formed in the second region 60
and flows out in a downward direction of the fin 30.
[0084] The hydrophilic agent may include a substance having at
least one of a carboxyl group (--COOH), an alcohol group (--OH), an
amine group (--NH.sub.2), a sulfonic acid group (--SO.sub.3H) and a
urea group (--NHCONH.sub.2).
[0085] The hydrophobic agent comprises a substance comprising at
least one of an inorganic nanopowder and a fluorine compound.
[0086] In addition, the hydrophobic agent may comprise a nanopowder
containing at least one of Al.sub.2O.sub.3, TiO.sub.2 and
SiO.sub.2.
[0087] In addition, the fluorine compound used as the hydrophobic
agent may comprise polytetrafluoroethylene (PTFE).
[0088] The coating may be carried out by dipcoating, spraycoating,
vacuum evaporation or the like.
[0089] Dipcoating is a method for forming a coating film by
immersing an object to be coated in a coating solution or slurry to
form a precursor layer on a surface of the object and baking the
precursor layer at a suitable temperature.
[0090] Spraycoating is a coating method which includes spraying
compressed air or a coating material squeeze-pumped into a fog
state on a surface of an object using a spray.
[0091] Vacuum evaporation is a coating method in which a metal is
heated at a high-temperature to produce a vapor and the metal is
deposited as a thin film using the vapor.
[0092] A patterning method may be used to coat the first region 50
and the second region 60 with a hydrophilic agent and/or a
hydrophobic agent, respectively, which have different surface
energies.
[0093] Specifically, one of the first region 50 and the second
region 60 is covered with a mask, the entire surface of the fin 30
is coated with a hydrophobic agent, the mask is removed and the
region covered with the mask is coated with a hydrophilic
agent.
[0094] Alternatively, one of the first region 50 and the second
region 60 is covered with a mask, the entire surface of the fin 30
is coated with a hydrophilic agent, the mask is removed and the
region covered with the mask is coated with a hydrophobic
agent.
[0095] Meanwhile, one of the first region 50 and the second region
60 is coated with a hydrophilic agent and the region not-coated
with the hydrophilic agent is coated with a hydrophobic agent by
dipcoating.
[0096] Alternatively, one of the first region 50 and the second
region 60 is coated with a hydrophobic agent and the region
not-coated with the hydrophilic agent is coated with a hydrophilic
agent by dipcoating.
[0097] At least one surface of the fin 30 may be coated.
[0098] The refrigerant pipe 20 may be also coated with a
hydrophilic agent or a hydrophobic agent.
[0099] By thinly coating the refrigerant pipe 20 and the fin 30
with a hydrophilic agent or a hydrophobic agent, thermal
conductivity of the heat exchanger 10 is improved, surface
roughness is decreased and discharge of the condensation water 70
is thus advantageous.
[0100] FIGS. 4A to 4D are views illustrating a boundary formed on a
fin provided in the heat exchanger according to the present
embodiment.
[0101] Based on the boundary 80 formed on the surface of the fin
30, the first region 50 and the second region 60 are divided.
[0102] As shown in FIGS. 4A and 4B, the boundary 80 may have a bent
straight line shape.
[0103] In addition, as shown in FIGS. 4C and 4D, the boundary 80
may have a curved shape.
[0104] The boundary 80 may have a curved shape including
continuously repeated ridges and valleys.
[0105] The boundary 80 may have a shape in which a straight line is
combined with a curve.
[0106] The shape of the boundary 80 may be varied and is not
limited to the examples described above.
[0107] FIG. 5 is a perspective view illustrating a schematic
structure of an outdoor unit for an air-conditioner, including the
heat exchanger according to the present embodiment.
[0108] The air-conditioner may be classified into a separation-type
and an integrated type. Of these, the separation-type
air-conditioner includes an indoor unit which is mounted indoors
and absorbs indoor air and thereby exchanges heat with a
refrigerant and emits the heat-exchanged air indoors again, and an
outdoor unit which heat-exchanges the refrigerant received from the
indoor unit with outside air and makes the refrigerant into a state
which may heat-exchange with indoor air again and supplies the same
to the indoor unit.
[0109] As shown in FIG. 5, an outdoor unit for air conditioners 100
may include a body 1 to form an outer appearance and a partition 2
to divide an inner space of the body 1.
[0110] The inner space of the body 1 is divided into a
heat-exchange area 3 and a compression area 4 by the partition 2.
The heat-exchange area 3 is provided with a heat exchanger 10 which
is bent along the insides of a back surface 5 and a left surface 6
of the body 1, and an air blower 7 which admits outside air so as
to facilitate heat-exchange by the heat exchanger 10. An absorption
unit 8 to absorb outside air is formed on the back surface 5 and
the left surface 6 of the body 1 and a discharge unit 11 to
discharge the heat-exchanged air is formed on a front surface 9 of
the body 1.
[0111] A compression unit 12 to compress the refrigerant supplied
from the indoor unit (not shown) is mounted on the compression area
4 of the body 1. A plurality of openings 14 to connect the
compression area 4 to the outside are formed on a right surface 13
of the body 1.
[0112] As shown in FIG. 1, the heat exchanger 10 may include a
refrigerant pipe 20, through which the refrigerant flows, and a
plurality of fins 30 connected to an outer circumference surface of
the refrigerant pipe 20.
[0113] The fin 30 may include a first region 50 disposed upstream
with respect to an air flow direction and a second region 60 which
forms a boundary with the first region 50 and is disposed
downstream with respect to the air flow direction.
[0114] The first region 50 and the second region 60 may be coated
such that there is a difference in surface energy therebetween, so
as to prevent occurrence of frosting on the fin 30.
[0115] Specifically, when the first region 50 is coated with a
hydrophobic agent having a low surface energy, the second region 60
may be coated with a hydrophilic agent or be uncoated.
[0116] When the first region 50 is coated with a hydrophilic agent
having a high surface energy, the second region 60 may be coated
with a hydrophobic agent or be uncoated.
[0117] When the first region 50 is uncoated, the second region 60
may be coated with a hydrophilic agent or be uncoated.
[0118] The first region 50 may have a constant width.
[0119] The first region 50 may have a width of 5 mm or less in a
longitudinal direction of the fin 30.
[0120] The heat exchanger 10 may be applied to an outdoor unit for
air-conditioners 100 as well as to an indoor unit for air
conditioners.
[0121] The heat exchanger 10 may be applied to not only to air
conditioners but also to refrigerators.
[0122] By coating fins with a thin film, formation of condensation
water and occurrence of frosting are prevented and, although the
condensation water is formed, discharge of the condensation water
is facilitated.
[0123] By coating fins with a thin film, formation of fog or ice is
prevented, heat exchange efficiency is improved, and microorganism
propagation and foreign matter decay caused by condensation water
are prevented.
[0124] Although a few embodiments of the present disclosure have
been shown and described, it would be appreciated by those skilled
in the art that changes may be made in these embodiments without
departing from the principles and spirit of the invention, the
scope of which is defined in the claims and their equivalents.
* * * * *