U.S. patent application number 10/558262 was filed with the patent office on 2007-03-08 for heat exchanger fin, heat exchanger, condensers, and evaporators.
This patent application is currently assigned to SHOWA DENKO K.K.. Invention is credited to Shinobu Yamauchi.
Application Number | 20070051502 10/558262 |
Document ID | / |
Family ID | 37828988 |
Filed Date | 2007-03-08 |
United States Patent
Application |
20070051502 |
Kind Code |
A1 |
Yamauchi; Shinobu |
March 8, 2007 |
Heat exchanger fin, heat exchanger, condensers, and evaporators
Abstract
A heat exchanger fin, capable of improving heat transfer rate
while preventing generation of heat bypass flow, such as a louver
fin provided with a plurality louvers arranged at certain intervals
in the introduction direction of air. The louvers are formed by
cutting and bending the heat exchanger fin so that the air is
passed while being guided by the louvers. The plurality of louvers
include louvers different in louver width, the louver width being
defined by a length of the louver along which the heat medium
passes. Wider louvers and narrower louvers can be arranged
alternatively.
Inventors: |
Yamauchi; Shinobu;
(OYAMA-SHI, JP) |
Correspondence
Address: |
OBLON, SPIVAK, MCCLELLAND, MAIER & NEUSTADT, P.C.
1940 DUKE STREET
ALEXANDRIA
VA
22314
US
|
Assignee: |
SHOWA DENKO K.K.
13-9, SHIBA DAIMON 1-CHOME, MINATO-KU
TOKYO
JP
105-8518
|
Family ID: |
37828988 |
Appl. No.: |
10/558262 |
Filed: |
May 19, 2004 |
PCT Filed: |
May 19, 2004 |
PCT NO: |
PCT/JP04/07160 |
371 Date: |
November 21, 2005 |
Current U.S.
Class: |
165/151 ;
29/890.047; 62/507; 62/515 |
Current CPC
Class: |
Y10T 29/4938 20150115;
F28F 2215/04 20130101; F28F 1/128 20130101 |
Class at
Publication: |
165/151 ;
029/890.047; 062/507; 062/515 |
International
Class: |
F28D 1/04 20060101
F28D001/04; F25B 39/04 20060101 F25B039/04; F25B 39/02 20060101
F25B039/02; B21D 53/06 20060101 B21D053/06 |
Claims
1. A heat exchanger fin, comprising: a heat transfer plate disposed
in parallel to a heat medium introduction direction and provided
with a plurality louvers arranged at certain intervals in the heat
medium introduction direction, said plurality of louvers being
formed by cutting and bending said heat transfer plate so that the
heat medium is passed while being guided by said plurality of
louvers, wherein said plurality of louvers include plural kinds of
louvers different in louver width, said louver width being defined
by a length of said louver along which the heat medium passes, and
wherein said plural kinds of louvers different in louver width are
disposed in a mixed arrangement along the heat medium introduction
direction.
2. The heat exchanger fin as recited in claim 1, wherein said
plurality of louvers include wide louvers each having a wide louver
width and narrow louvers each having a narrow louver width, wherein
said wide louvers and said narrow louvers are disposed in a mixed
arrangement.
3. The heat exchanger fin as recited in claim 2, wherein one or a
plurality of said wide louvers and one or a plurality of said
narrow louvers are arranged alternatively.
4. The heat exchanger fin as recited in claim 2, wherein said wide
louver and said narrow louver are arranged alternatively.
5. The heat exchanger fin as recited in claim 2, wherein when a
louver width of said wide louver and a louver width of said narrow
louver are represented as "Lwl" and "Lws," respectively, a ratio
"Lws/Lwl" of said louver width "Lws" of said narrow louver to said
louver width "Lwl" of said wide louver is set to 0.1 to 0.7.
6. The heat exchanger fin as recited in claim 1, wherein an angle
of said louver with respect to said heat transfer plate is set to
22 to 36.degree..
7. The heat exchanger fin as recited in claim 1, wherein a
plurality of said heat transfer plates are arranged in parallel
with each other at certain intervals in a direction perpendicular
to the heat medium introduction direction to form an air passage
between adjacent heat transfer plates.
8. The heat exchanger fin as recited in claim 7, wherein a fin
pitch defined by a distance between adjacent heat transfer plates
is set to 1 to 2 mm.
9. The heat exchanger fin as recited in claim 7, wherein when a fin
pitch defined by a distance between adjacent heat transfer plates
is represented as "Fp" and a louver width of a widest louver having
a widest width is represented as "Lwmax," a ratio "Fp/Lwmax" of
said fin pitch "Fp" with respect to said louver width "Lwmax" is
set to 1 or more.
10. The heat exchanger fin as recited in claim 1, wherein said heat
transfer plate is disposed between said pair of heat exchanging
tubes arranged in parallel with each other at a certain distance to
exchange heat between air as a heat medium passing through said
pair of heat exchanging tubes and refrigerant passing through said
heat exchanging tube.
11. The heat exchanger fin as recited in claim 10, wherein it is
configured such that refrigerant is condensed by exchanging heat
with air.
12. The heat exchanger fin as recited in claim 10, wherein it is
configured such that refrigerant is evaporated by exchanging heat
with air.
13. A louver fin, comprising: a heat transfer plate disposed in
parallel to a heat medium introduction direction and provided with
a plurality louvers arranged at certain intervals in the heat
medium introduction direction, said plurality of louvers being
formed by cutting and bending said heat transfer plate so that the
heat medium is passed while being guided by said plurality of
louvers, wherein said plurality of louvers include plural kinds of
louvers different in louver width, said louver width being defined
by a length of said louver along which the heat medium passes, and
wherein said plural kinds of louvers different in louver width are
disposed in a mixed arrangement along the heat medium introduction
direction.
14. A corrugated fin, comprising: a plurality of heat transfer
plates disposed in parallel to a heat medium introduction direction
and arranged in parallel at certain intervals in a direction
perpendicular to the heat medium introduction direction with
adjacent heat transfer plates connected with each other, each of
said plurality of heat transfer plates being provided with a
plurality louvers arranged at certain intervals in the heat medium
introduction direction, said plurality of louvers being formed by
cutting and bending said heat transfer plate so that the heat
medium is passed while being guided by said plurality of louvers,
wherein said plurality of louvers include plural kinds of louvers
different in louver width, said louver width being defined by a
length of said louver along which the heat medium passes, and
wherein said plural kinds of louvers different in louver width are
disposed in a mixed arrangement.
15. A heat exchanger, comprising a plurality of heat exchanger fins
disposed in parallel to an air introduction direction and arranged
in parallel at certain intervals in a direction perpendicular to
the air introduction direction, and a refrigerant passage through
which refrigerant passes, each of said plurality of heat transfer
plates being provided with a plurality louvers arranged at certain
intervals in the air introduction direction, said plurality of
louvers being formed by cutting and bending said heat exchanger fin
so that the air is passed while being guided by said plurality of
louvers to exchange heat between the air and the refrigerant,
wherein said plurality of louvers include plural kinds of louvers
different in louver width, said louver width being defined by a
length of said louver along which the heat medium passes, and
wherein said plural kinds of louvers different in louver width are
disposed in a mixed arrangement.
16. A heat exchanger, comprising a pair of heat exchanging tubes
disposed in parallel at a certain interval, and a plurality of heat
exchanger fins each disposed in parallel to an air introduction
direction and arranged in parallel with each other at certain
intervals in a direction perpendicular to the air introduction
direction, and each of said plurality of heat exchanger fins being
provided with a plurality louvers arranged at certain intervals in
the air introduction direction, said plurality of louvers being
formed by cutting and bending said heat exchanger fin so that the
air is passed while being guided by said plurality of louvers to
exchange heat between the air and the refrigerant, wherein said
plurality of louvers include plural kinds of louvers different in
louver width, said louver width being defined by a length of said
louver along which the air passes, and wherein said plural kinds of
louvers different in louver width are disposed in a mixed
arrangement.
17. The heat exchanger as recited in claim 15, wherein said
plurality of louvers include wide louvers each having a wide louver
width and narrow louvers each having a narrow louver width, wherein
said wide louvers and said narrow louvers are disposed in a mixed
arrangement.
18. The heat exchanger as recited in claim 15, wherein adjacent
fins among said plurality of heat exchanger fins are joined with
each other.
19. A condenser, comprising a plurality of heat exchanger fins
disposed in parallel to an air introduction direction and arranged
in parallel at certain intervals in a direction perpendicular to
the air introduction direction, and a refrigerant passage through
which refrigerant passes, each of said plurality of heat transfer
plates being provided with a plurality of louvers arranged at
certain intervals in the air introduction direction, said plurality
of louvers being formed by cutting and bending said heat exchanger
fin so that the air is passed while being guided by said plurality
of louvers to condense the refrigerant by exchanging heat between
the air and the refrigerant, wherein said plurality of louvers
include plural kinds of louvers different in louver width, said
louver width being defined by a length of said louver along which
the heat medium passes, and wherein said plural kinds of louvers
different in louver width are disposed in a mixed arrangement.
20. A condenser, comprising a pair of heat exchanging tubes
disposed in parallel at a certain interval, and a plurality of heat
exchanger fins each disposed in parallel to an air introduction
direction and arranged in parallel with each other at certain
intervals in a direction perpendicular to the air introduction
direction, and each of said plurality of heat exchanger fins being
provided with a plurality of louvers arranged at certain intervals
in the air introduction direction, said plurality of louvers being
formed by cutting and bending said heat exchanger fin so that the
air is passed while being guided by said plurality of louvers to
condense refrigerant by exchanging heat between the air and the
refrigerant, wherein said plurality of louvers include plural kinds
of louvers different in louver width, said louver width being
defined by a length of said louver along which the air passes, and
wherein said plural kinds of louvers different in louver width are
disposed in a mixed arrangement.
21. The condenser as recited in claim 19, wherein said plurality of
louvers include wide louvers each having a wide louver width and
narrow louvers each having a narrow louver width, wherein said wide
louvers and said narrow louvers are disposed in a mixed
arrangement.
22. The condenser as recited in claim 19, wherein adjacent fins
among said plurality of heat exchanger fins are joined with each
other.
23. A condenser for use in car air-conditioning refrigeration
cycles, comprising: a plurality of heat exchanger fins disposed in
parallel to an air introduction direction and arranged in parallel
at certain intervals in a direction perpendicular to the air
introduction direction; and a refrigerant passage through which
refrigerant passes, wherein each of said plurality of heat transfer
plates is provided with a plurality of louvers arranged at certain
intervals in the air introduction direction, said plurality of
louvers being formed by cutting and bending said heat exchanger fin
so that the air is passed while being guided by said plurality of
louvers to condense the refrigerant by exchanging heat between the
air and the refrigerant, and wherein said plurality of louvers
include plural kinds of louvers different in louver width, said
louver width being defined by a length of said louver along which
the heat medium passes, and wherein said plural kinds of louvers
different in louver width are disposed in a mixed arrangement.
24. A condenser for use in car air-conditioning refrigeration
cycles, comprising: a pair of heat exchanging tubes disposed in
parallel at a certain interval; and a plurality of heat exchanger
fins each disposed in parallel to an air introduction direction and
arranged in parallel with each other at certain intervals in a
direction perpendicular to the air introduction direction, wherein
each of said plurality of heat exchanger fins is provided with a
plurality of louvers arranged at certain intervals in the air
introduction direction, said plurality of louvers being formed by
cutting and bending said heat exchanger fin so that the air is
passed while being guided by said plurality of louvers to condense
refrigerant by exchanging heat between the air and the refrigerant,
wherein said plurality of louvers include plural kinds of louvers
different in louver width, said louver width being defined by a
length of said louver along which the air passes, and wherein said
plural kinds of louvers different in louver width are disposed in a
mixed arrangement.
25. An evaporator, comprising a plurality of heat exchanger fins
disposed in parallel to an air introduction direction and arranged
in parallel at certain intervals in a direction perpendicular to
the air introduction direction, and a refrigerant passage through
which refrigerant passes, each of said plurality of heat transfer
plates being provided with a plurality of louvers arranged at
certain intervals in the air introduction direction, said plurality
of louvers being formed by cutting and bending said heat exchanger
fin so that the air is passed while being guided by said plurality
of louvers to evaporate the refrigerant by exchanging heat between
the air and the refrigerant, wherein said plurality of louvers
include plural kinds of louvers different in louver width, said
louver width being defined by a length of said louver along which
the heat medium passes, and wherein said plural kinds of louvers
different in louver width are disposed in a mixed arrangement.
26. An evaporator, comprising a pair of heat exchanging tubes
disposed in parallel at a certain interval, and a plurality of heat
exchanger fins each disposed in parallel to an air introduction
direction and arranged in parallel with each other at certain
intervals in a direction perpendicular to the air introduction
direction, and each of said plurality of heat exchanger fins being
provided with a plurality of louvers arranged at certain intervals
in the air introduction direction, said plurality of louvers being
formed by cutting and bending said heat exchanger fin so that the
air is passed while being guided by said plurality of louvers to
evaporate refrigerant by exchanging heat between the air and the
refrigerant, wherein said plurality of louvers include plural kinds
of louvers different in louver width, said louver width being
defined by a length of said louver along which the air passes, and
wherein said plural kinds of louvers different in louver width are
disposed in a mixed arrangement.
27. The evaporator as recited in claim 25, wherein said plurality
of louvers include wide louvers each having a wide louver width and
narrow louvers each having a narrow louver width, wherein said wide
louvers and said narrow louvers are disposed in a mixed
arrangement.
28. The evaporator as recited in claim 25, wherein adjacent fins
among said plurality of heat exchanger fins are joined with each
other.
29. An evaporator for use in car air-conditioning refrigeration
cycles, comprising: a plurality of heat exchanger fins disposed in
parallel to an air introduction direction and arranged in parallel
at certain intervals in a direction perpendicular to the air
introduction direction; and a refrigerant passage through which
refrigerant passes, wherein each of said plurality of heat transfer
plates is provided with a plurality of louvers arranged at certain
intervals in the air introduction direction, said plurality of
louvers being formed by cutting and bending said heat exchanger fin
so that the air is passed while being guided by said plurality of
louvers to evaporate the refrigerant by exchanging heat between the
air and the refrigerant, and wherein said plurality of louvers
include plural kinds of louvers different in louver width, said
louver width being defined by a length of said louver along which
the heat medium passes, and wherein said plural kinds of louvers
different in louver width are disposed in a mixed arrangement.
30. An evaporator for use in car air-conditioning refrigeration
cycles, comprising: a pair of heat exchanging tubes disposed in
parallel at a certain interval; and a plurality of heat exchanger
fins each disposed in parallel to an air introduction direction and
arranged in parallel with each other at certain intervals in a
direction perpendicular to the air introduction direction, wherein
each of said plurality of heat exchanger fins is provided with a
plurality of louvers arranged at certain intervals in the air
introduction direction, said plurality of louvers being formed by
cutting and bending said heat exchanger fin so that the air is
passed while being guided by said plurality of louvers to evaporate
the refrigerant by exchanging heat between the air and the
refrigerant, wherein said plurality of louvers include plural kinds
of louvers different in louver width, said louver width being
defined by a length of said louver along which the air passes, and
wherein said plural kinds of louvers different in louver width are
disposed in a mixed arrangement.
Description
[0001] Priority is claimed to Japanese Patent Application No.
2003-140400 filed on May 19, 2003, and U.S. Provisional Application
No. 60/478,360 filed on Jun. 16, 2003, the disclosure of which are
incorporated by reference in their entireties.
CROSS REFERENCE TO RELATED APPLICATIONS
[0002] This application is an application filed under 35 U.S.C.
.sctn. 111(a) claiming the benefit pursuant to 35 U.S.C. .sctn.
119(e) (1) of the filing date of Provisional Application No.
60/478,360 filed on Jun. 16, 2003 pursuant to 35 U.S.C. .sctn. 111
(b).
TECHNICAL FIELD
[0003] The present invention relates to a heat exchanger such as a
car air-conditioning condenser or evaporator for use in car
air-conditioning refrigeration cycles as a car air-conditioning
apparatus for example. It also relates to a fin for use in heat
exchangers (hereinafter referred to as "heat exchanger fin") such
as a louver fin or a corrugated fin to be equipped to the
aforementioned apparatuses.
BACKGROUND ART
[0004] A heat exchanger such as an evaporator or a condenser for
use in car air-conditioning refrigeration cycles includes a heat
exchanging tube through which refrigerant passes and a heat
exchanger fin disposed perpendicular to the longitudinal direction
of the heat exchanging tube, so that heat exchanging is performed
between the ambient air and the refrigerant passing through the
heat exchanging tube via the fin.
[0005] As a heat exchanger fin, depending on the usage and/or
required performance, a louver fin, an offset fin, a pin fin and
the like has been commonly used.
[0006] Among heat exchanges, in a louver fin type heat exchanger,
as shown in FIG. 11, a plurality of louver fins 50 arranged in
parallel to the introduction direction X of the air A are arranged
in parallel with each other at certain intervals in the direction
perpendicular to the air introduction direction X, thereby forming
an air passages 60 between the adjacent louver fins 50. Each louver
fin 50 is provided with a plurality of cut-and-bent louvers 51
arranged in the longitudinal direction (air introduction direction)
of the air passage 60. The air A introduced in each air passage 60
passes through the louver gaps each formed between the adjacent
louvers 51 of each louver fin 50 along the louvers 51, thereby
exchanging heat between the air A and the refrigerant passing
through the heat exchanging tube (not shown).
[0007] As one of the methods for improving the thermal performance
in such heat exchangers, it may be considered effective to increase
the contact area between the windward side edges of the louvers 51
and the air A by decreasing the pitch of the louvers 51 to increase
the number of louvers 51.
[0008] However, the smaller louver pitch may cause clogging of sand
and/or bridging of condensed water between the adjacent louvers 51,
preventing the air A passing through the air passage 60 from being
introduced into the louver gaps each formed between the adjacent
louvers 51. This causes the bypass flow of the air A, i.e., the air
flow passing through the fin spaces each formed between the
adjacent louver fins 50 without being introduced into the louver
gaps, resulting in a deterioration of the heat transfer rate.
[0009] On the other hand, in a louver fin type heat exchanger,
Japanese Unexamined Laid-open Patent Publication No. H6-221787
(FIGS. 1 and 3) and U.S. Pat. No. 5,730,214 (FIGS. 5 to 7) disclose
techniques for improving the heat exchanging performance by
changing the angle of the louver.
[0010] Furthermore, disclosed in Japanese Unexamined Laid-open
Patent Publication No. H1-263498 (pages 1 to 2) is a technique in
which the optimal values of the fin pitch, the fin thickness, the
louver pitch and the louver angle are defined.
[0011] In the recent technical field of heat exchangers, especially
in the technical field of car air-conditioning heat exchangers,
however, it is requested to further improve the heat exchanging
performance. Therefore it is also requested to further improve the
heat transfer rate of the heat exchanger fin.
[0012] It is an object of the present invention to provide a heat
exchanger such as a car air-conditioning condenser or evaporator
improved in heat transfer rate and therefore excellent in heat
exchanging performance.
[0013] It is another object of the present invention to provide a
heat exchanger fin such as a louver fin and a corrugated fin to be
equipped to the aforementioned heat exchangers.
DISCLOSURE OF INVENTION
[0014] In order to attain the aforementioned objects, the present
invention has the following features.
[0015] [1] A heat exchanger fin, comprising:
[0016] a heat transfer plate disposed in parallel to a heat medium
introduction direction and provided with a plurality louvers
arranged at certain intervals in the heat medium introduction
direction, said plurality of louvers being formed by cutting and
bending said heat transfer plate so that the heat medium is passed
while being guided by said plurality of louvers,
[0017] wherein said plurality of louvers include plural kinds of
louvers different in louver width, said louver width being defined
by a length of said louver along which the heat medium passes,
and
[0018] wherein said plural kinds of louvers different in louver
width are disposed in a mixed arrangement along the heat medium
introduction direction.
[0019] In the heat exchanger fin according to the present
invention, since a plurality of louvers include plural kinds of
louvers different in louver width, the heat medium such as air will
be assuredly introduced into the gaps each formed between the
adjacent louvers to flow smoothly along each louver, resulting in
improved heat transfer rate by preventing generation of bypass flow
of the heat medium.
[0020] [2] The heat exchanger fin as recited in the aforementioned
Item [1], wherein said plurality of louvers include wide louvers
each having a wide louver width and narrow louvers each having a
narrow louver width, wherein said wide louvers and said narrow
louvers are disposed in a mixed arrangement.
[0021] [3] The heat exchanger fin as recited in the aforementioned
Item [2], wherein one or a plurality of said wide louvers and one
or a plurality of said narrow louvers are arranged
alternatively.
[0022] [4] The heat exchanger fin as recited in the aforementioned
Item [2], wherein said wide louver and said narrow louver are
arranged alternatively.
[0023] In the invention as recited in the aforementioned Items [2]
to [4], since two kinds of louvers are employed, the heat transfer
rate can be further improved without complicating the
structure.
[0024] [5] The heat exchanger fin as recited in any one of the
aforementioned Items [2] to [4], wherein when a louver width of
said wide louver and a louver width of said narrow louver are
represented as "Lwl" and "Lws," respectively, a ratio "Lws/Lwl" of
said louver width "Lws" of said narrow louver to said louver width
"Lwl" of said wide louver is set to 0.1 to 0.7.
[0025] [6] The heat exchanger fin as recited in any one of the
aforementioned Items [1] to [5], wherein an angle of said louver
(louver angle) with respect to said heat transfer plate is set to
22 to 36.degree..
[0026] In the invention as recited in the aforementioned Items [5]
and [6], the heat transfer rate can be further improved.
[0027] [7] The heat exchanger fin as recited in any one of the
aforementioned Items [1] to [6], wherein a plurality of said heat
transfer plates are arranged in parallel with each other at certain
intervals in a direction perpendicular to the heat medium
introduction direction to form an air passage between adjacent heat
transfer plates.
[0028] As will be understood from the aforementioned Item [7], the
present invention can be preferably employed as corrugated fins or
plate fins.
[0029] [8] The heat exchanger fin as recited in the aforementioned
Item [7], wherein a fin pitch defined by a distance between
adjacent heat transfer plates is set to 1 to 2 mm.
[0030] In the invention as recited in the aforementioned Item [8],
the heat transfer rate can be further improved.
[0031] [9] The heat exchanger fin as recited in the aforementioned
Item [7] or [8], wherein when a fin pitch defined by a distance
between adjacent heat transfer plates is represented as "Fp" and a
louver width of a widest louver having a widest width is
represented as "Lwmax," a ratio "Fp/Lwmax" of said fin pitch "Fp"
with respect to said louver width "Lwmax" is set to 1 or more.
[0032] In the invention as recited in the aforementioned Item [9],
the heat transfer rate can be further improved.
[0033] [10] The heat exchanger fin as recited in any one of the
aforementioned Items [1] to [9], wherein said heat transfer plate
is disposed between said pair of heat exchanging tubes arranged in
parallel with each other at a certain distance to exchange heat
between air as a heat medium passing through said pair of heat
exchanging tubes and refrigerant passing through said heat
exchanging tube.
[0034] As will be understood from the aforementioned Item [10], the
present invention can be preferably employed in tube type heat
exchangers.
[0035] [11] The heat exchanger fin as recited in the aforementioned
Item [10], wherein it is configured such that refrigerant is
condensed by exchanging heat with air.
[0036] As will be understood from the aforementioned Item [11], the
present invention can be preferably employed in condensers.
[0037] [12] The heat exchanger fin as recited in the aforementioned
Item [10], wherein it is configured such that refrigerant is
evaporated by exchanging heat with air.
[0038] As will be understood from the aforementioned Item [12], the
present invention can be preferably employed in evaporators.
[0039] The preferable features as recited in the aforementioned
Items [2[ to [12] can also be employed in the following Items [13]
to [30].
[0040] [13] A louver fin, comprising:
[0041] a heat transfer plate disposed in parallel to a heat medium
introduction direction and provided with a plurality louvers
arranged at certain intervals in the heat medium introduction
direction, said plurality of louvers being formed by cutting and
bending said heat transfer plate so that the heat medium is passed
while being guided by said plurality of louvers,
[0042] wherein said plurality of louvers include plural kinds of
louvers different in louver width, said louver width being defined
by a length of said louver along which the heat medium passes,
and
[0043] wherein said plural kinds of louvers different in louver
width are disposed in a mixed arrangement along the heat medium
introduction direction.
[0044] In the louver fin according to the invention, in the same
manner as mentioned above, the heat medium such as air will be
assuredly introduced in between louvers to flow smoothly along each
louver, enabling improvement of the heat transfer rate by
preventing generation of bypass flow.
[0045] [14] A corrugated fin, comprising:
[0046] a plurality of heat transfer plates disposed in parallel to
a heat medium introduction direction and arranged in parallel at
certain intervals in a direction perpendicular to the heat medium
introduction direction with adjacent heat transfer plates connected
with each other, each of said plurality of heat transfer plates
being provided with a plurality louvers arranged at certain
intervals in the heat medium introduction direction, said plurality
of louvers being formed by cutting and bending said heat transfer
plate so that the heat medium is passed while being guided by said
plurality of louvers,
[0047] wherein said plurality of louvers include plural kinds of
louvers different in louver width, said louver width being defined
by a length of said louver along which the heat medium passes,
and
[0048] wherein said plural kinds of louvers different in louver
width are disposed in a mixed arrangement.
[0049] In the corrugated fin according to the invention, in the
same manner as mentioned above, the heat medium such as air will be
assuredly introduced in between louvers to flow smoothly along each
louver, enabling improvement of the heat transfer rate by
preventing generation of bypass flow.
[0050] [15] A heat exchanger, comprising a plurality of heat
exchanger fins disposed in parallel to an air introduction
direction and arranged in parallel at certain intervals in a
direction perpendicular to the air introduction direction, and a
refrigerant passage through which refrigerant passes, each of said
plurality of heat transfer plates being provided with a plurality
louvers arranged at certain intervals in the air introduction
direction, said plurality of louvers being formed by cutting and
bending said heat exchanger fin so that the air is passed while
being guided by said plurality of louvers to exchange heat between
the air and the refrigerant,
[0051] wherein said plurality of louvers include plural kinds of
louvers different in louver width, said louver width being defined
by a length of said louver along which the heat medium passes,
and
[0052] wherein said plural kinds of louvers different in louver
width are disposed in a mixed arrangement.
[0053] In the heat exchanger according to the invention, in the
same manner as mentioned above, the heat medium such as air will be
assuredly introduced in between louvers to flow smoothly along each
louver, enabling improvement of the heat transfer rate by
preventing generation of bypass flow.
[0054] [16] A heat exchanger, comprising a pair of heat exchanging
tubes disposed in parallel at a certain interval, and a plurality
of heat exchanger fins each disposed in parallel to an air
introduction direction and arranged in parallel with each other at
certain intervals in a direction perpendicular to the air
introduction direction, and each of said plurality of heat
exchanger fins being provided with a plurality louvers arranged at
certain intervals in the air introduction direction, said plurality
of louvers being formed by cutting and bending said heat exchanger
fin so that the air is passed while being guided by said plurality
of louvers to exchange heat between the air and the
refrigerant,
[0055] wherein said plurality of louvers include plural kinds of
louvers different in louver width, said louver width being defined
by a length of said louver along which the air passes, and
[0056] wherein said plural kinds of louvers different in louver
width are disposed in a mixed arrangement.
[0057] In the heat exchanger according to the invention, in the
same manner as mentioned above, the heat medium such as air will be
assuredly introduced in between louvers to flow smoothly along each
louver, enabling improvement of the heat transfer rate by
preventing generation of bypass flow.
[0058] [17] The heat exchanger as recited in the aforementioned
Item [15] or [16], wherein said plurality of louvers include wide
louvers each having a wide louver width and narrow louvers each
having a narrow louver width, wherein said wide louvers and said
narrow louvers are disposed in a mixed arrangement.
[0059] In the invention as recited in the aforementioned Item [17],
in the same manner as mentioned above, the heat transfer rate can
be further improved.
[0060] [18] The heat exchanger as recited in the aforementioned
Item [15] or [16], wherein adjacent fins among said plurality of
heat exchanger fins are joined with each other.
[0061] As will be understood from the aforementioned Item [18], the
present invention can be preferably employed in corrugated type
heat exchangers.
[0062] [19] A condenser, comprising a plurality of heat exchanger
fins disposed in parallel to an air introduction direction and
arranged in parallel at certain intervals in a direction
perpendicular to the air introduction direction, and a refrigerant
passage through which refrigerant passes, each of said plurality of
heat transfer plates being provided with a plurality louvers
arranged at certain intervals in the air introduction direction,
said plurality of louvers being formed by cutting and bending said
heat exchanger fin so that the air is passed while being guided by
said plurality of louvers to condense the refrigerant by exchange
heat between the air and the refrigerant,
[0063] wherein said plurality of louvers include plural kinds of
louvers different in louver width, said louver width being defined
by a length of said louver along which the heat medium passes,
and
[0064] wherein said plural kinds of louvers different in louver
width are disposed in a mixed arrangement.
[0065] In the condenser according to the invention, in the same
manner as mentioned above, the heat medium such as air will be
assuredly introduced in between louvers to flow smoothly along each
louver, enabling improvement of the heat transfer rate by
preventing generation of bypass flow.
[0066] [20] A condenser, comprising a pair of heat exchanging tubes
disposed in parallel at a certain interval, and a plurality of heat
exchanger fins each disposed in parallel to an air introduction
direction and arranged in parallel with each other at certain
intervals in a direction perpendicular to the air introduction
direction, and each of said plurality of heat exchanger fins being
provided with a plurality louvers arranged at certain intervals in
the air introduction direction, said plurality of louvers being
formed by cutting and bending said heat exchanger fin so that the
air is passed while being guided by said plurality of louvers to
condense refrigerant by exchanging heat between the air and the
refrigerant,
[0067] wherein said plurality of louvers include plural kinds of
louvers different in louver width, said louver width being defined
by a length of said louver along which the air passes, and
[0068] wherein said plural kinds of louvers different in louver
width are disposed in a mixed arrangement.
[0069] In the condenser according to the invention, in the same
manner as mentioned above, the heat medium such as air will be
assuredly introduced in between louvers to flow smoothly along each
louver, enabling improvement of the heat transfer rate by
preventing generation of bypass flow.
[0070] [21] The condenser as recited in the aforementioned Item
[19] or [20], wherein said plurality of louvers include wide
louvers each having a wide louver width and narrow louvers each
having a narrow louver width, wherein said wide louvers and said
narrow louvers are disposed in a mixed arrangement.
[0071] In the invention as recited in the aforementioned Item [21],
in the same manner as mentioned above, the heat transfer rate can
be further improved.
[0072] [22] The condenser as recited in the aforementioned Item
[19] or [20], wherein adjacent fins among said plurality of heat
exchanger fins are joined with each other.
[0073] As will be understood from the aforementioned Item [22], the
present invention can be preferably employed in corrugated type
heat exchangers.
[0074] [23] A condenser for use in car air-conditioning
refrigeration cycles, comprising:
[0075] a plurality of heat exchanger fins disposed in parallel to
an air introduction direction and arranged in parallel at certain
intervals in a direction perpendicular to the air introduction
direction; and
[0076] a refrigerant passage through which refrigerant passes,
[0077] wherein each of said plurality of heat transfer plates is
provided with a plurality louvers arranged at certain intervals in
the air introduction direction, said plurality of louvers being
formed by cutting and bending said heat exchanger fin so that the
air is passed while being guided by said plurality of louvers to
condense the refrigerant by exchange heat between the air and the
refrigerant, and
[0078] wherein said plurality of louvers include plural kinds of
louvers different in louver width, said louver width being defined
by a length of said louver along which the heat medium passes,
and
[0079] wherein said plural kinds of louvers different in louver
width are disposed in a mixed arrangement.
[0080] In the car air-conditioning condenser according to the
invention, in the same manner as mentioned above, the heat medium
such as air will be assuredly introduced in between louvers to flow
smoothly along each louver, enabling improvement of the heat
transfer rate by preventing generation of bypass flow.
[0081] [24] A condenser for use in car air-conditioning
refrigeration cycles, comprising:
[0082] a pair of heat exchanging tubes disposed in parallel at a
certain interval; and
[0083] a plurality of heat exchanger fins each disposed in parallel
to an air introduction direction and arranged in parallel with each
other at certain intervals in a direction perpendicular to the air
introduction direction, wherein each of said plurality of heat
exchanger fins is provided with a plurality louvers arranged at
certain intervals in the air introduction direction, said plurality
of louvers being formed by cutting and bending said heat exchanger
fin so that the air is passed while being guided by said plurality
of louvers to condense refrigerant by exchanging heat between the
air and the refrigerant,
[0084] wherein said plurality of louvers include plural kinds of
louvers different in louver width, said louver width being defined
by a length of said louver along which the air passes, and
[0085] wherein said plural kinds of louvers different in louver
width are disposed in a mixed arrangement.
[0086] In the car air-conditioning condenser according to the
invention, in the same manner as mentioned above, the heat medium
such as air will be assuredly introduced in between louvers to flow
smoothly along each louver, enabling improvement of the heat
transfer rate by preventing generation of bypass flow.
[0087] [25] An evaporator, comprising a plurality of heat exchanger
fins disposed in parallel to an air introduction direction and
arranged in parallel at certain intervals in a direction
perpendicular to the air introduction direction, and a refrigerant
passage through which refrigerant passes, each of said plurality of
heat transfer plates being provided with a plurality louvers
arranged at certain intervals in the air introduction direction,
said plurality of louvers being formed by cutting and bending said
heat exchanger fin so that the air is passed while being guided by
said plurality of louvers to evaporate the refrigerant by exchange
heat between the air and the refrigerant,
[0088] wherein said plurality of louvers include plural kinds of
louvers different in louver width, said louver width being defined
by a length of said louver along which the heat medium passes,
and
[0089] wherein said plural kinds of louvers different in louver
width are disposed in a mixed arrangement.
[0090] In the evaporator according to the invention, in the same
manner as mentioned above, the heat medium such as air will be
assuredly introduced in between louvers to flow smoothly along each
louver, enabling improvement of the heat transfer rate by
preventing generation of bypass flow.
[0091] [26] An evaporator, comprising a pair of heat exchanging
tubes disposed in parallel at a certain interval, and a plurality
of heat exchanger fins each disposed in parallel to an air
introduction direction and arranged in parallel with each other at
certain intervals in a direction perpendicular to the air
introduction direction, and each of said plurality of heat
exchanger fins being provided with a plurality louvers arranged at
certain intervals in the air introduction direction, said plurality
of louvers being formed by cutting and bending said heat exchanger
fin so that the air is passed while being guided by said plurality
of louvers to evaporate refrigerant by exchanging heat between the
air and the refrigerant,
[0092] wherein said plurality of louvers include plural kinds of
louvers different in louver width, said louver width being defined
by a length of said louver along which the air passes, and
[0093] wherein said plural kinds of louvers different in louver
width are disposed in a mixed arrangement.
[0094] In the evaporator according to the invention, in the same
manner as mentioned above, the heat medium such as air will be
assuredly introduced in between louvers to flow smoothly along each
louver, enabling improvement of the heat transfer rate by
preventing generation of bypass flow.
[0095] [27] The evaporator as recited in the aforementioned Item 25
or 26, wherein said plurality of louvers include wide louvers each
having a wide louver width and narrow louvers each having a narrow
louver width, wherein said wide louvers and said narrow louvers are
disposed in a mixed arrangement.
[0096] In the invention as recited in the aforementioned Item [27],
in the same manner as mentioned above, the heat transfer rate can
be further improved.
[0097] [28] The evaporator as recited in the aforementioned Item
[25] or [26], wherein adjacent fins among said plurality of heat
exchanger fins are joined with each other.
[0098] As will be understood from the aforementioned Item [28], the
present invention can be preferably employed in corrugated type
evaporators.
[0099] [29] An evaporator for use in car air-conditioning
refrigeration cycles, comprising:
[0100] a plurality of heat exchanger fins disposed in parallel to
an air introduction direction and arranged in parallel at certain
intervals in a direction perpendicular to the air introduction
direction; and
[0101] a refrigerant passage through which refrigerant passes,
[0102] wherein each of said plurality of heat transfer plates is
provided with a plurality louvers arranged at certain intervals in
the air introduction direction, said plurality of louvers being
formed by cutting and bending said heat exchanger fin so that the
air is passed while being guided by said plurality of louvers to
evaporate the refrigerant by exchange heat between the air and the
refrigerant, and
[0103] wherein said plurality of louvers include plural kinds of
louvers different in louver width, said louver width being defined
by a length of said louver along which the heat medium passes,
and
[0104] wherein said plural kinds of louvers different in louver
width are disposed in a mixed arrangement.
[0105] In the evaporator according to the invention, in the same
manner as mentioned above, the heat medium such as air will be
assuredly introduced in between louvers to flow smoothly along each
louver, enabling improvement of the heat transfer rate by
preventing generation of bypass flow.
[0106] [30] An evaporator for use in car air-conditioning
refrigeration cycles, comprising:
[0107] a pair of heat exchanging tubes disposed in parallel at a
certain interval; and
[0108] a plurality of heat exchanger fins each disposed in parallel
to an air introduction direction and arranged in parallel with each
other at certain intervals in a direction perpendicular to the air
introduction direction, wherein each of said plurality of heat
exchanger fins is provided with a plurality louvers arranged at
certain intervals in the air introduction direction, said plurality
of louvers being formed by cutting and bending said heat exchanger
fin so that the air is passed while being guided by said plurality
of louvers to evaporate refrigerant by exchanging heat between the
air and the refrigerant,
[0109] wherein said plurality of louvers include plural kinds of
louvers different in louver width, said louver width being defined
by a length of said louver along which the air passes, and
[0110] wherein said plural kinds of louvers different in louver
width are disposed in a mixed arrangement.
[0111] In the evaporator according to the invention, in the same
manner as mentioned above, the heat medium such as air will be
assuredly introduced in between louvers to flow smoothly along each
louver, enabling improvement of the heat transfer rate by
preventing generation of bypass flow.
[0112] Another objects and advantages of the invention will be more
clearly apparent from the following explanations.
BRIEF DESCRIPTION OF DRAWINGS
[0113] FIG. 1 is a perspective cut-out explanatory view partially
showing a fin and its vicinity of a heat exchanger according to an
embodiment of the present invention.
[0114] FIG. 2 is an enlarged cross-sectional view taken along the
line P-P in FIG. 1 and showing the louver fin of the aforementioned
embodiment.
[0115] FIG. 3 is an enlarged cross-sectional view showing the fin
portion of the heat exchanger according to the aforementioned
embodiment.
[0116] FIGS. 4(a) to 4(e) show partial cross-sectional views of
louver fins according to modified embodiments of the present
invention.
[0117] FIG. 5 is a graph showing the relationship between the front
wind velocity and the heat transfer rate in the evaporators of
Examples 1 to 5 and Comparative Example 1.
[0118] FIG. 6 is a graph showing the relationship between the front
wind velocity and the heat transfer rate in the evaporators of
Examples 6 and 7 and Comparative Example 2.
[0119] FIG. 7 is a graph showing the relationship between the
louver angle and the heat transfer rate at the front wind velocity
of 1 m/s in the evaporators of Examples 8 and 9 and Comparative
Example 3.
[0120] FIG. 8 is a graph showing the relationship between the
louver angle and the heat transfer rate at the front wind velocity
of 2 m/s in the evaporators of Examples 8 and 9 and Comparative
Example 3.
[0121] FIG. 9 is a graph showing the relationship between the fin
pitch and the heat transfer rate at the front wind velocity of 1
m/s in the evaporators of Examples 9 and 10 and Comparative Example
4.
[0122] FIG. 10 is a graph showing the relationship between the fin
pitch and the heat transfer rate at the front wind velocity of 2
m/s in the evaporators of Examples 10 and 11 and Comparative
Example 4.
[0123] FIG. 11 is a cross-sectional view showing a part of louver
fins of a conventional heat exchanger.
BEST MODE FOR CARRYING OUT THE INVENTION
[0124] FIG. 1 is a perspective cut-out explanatory view partially
showing a fin and its vicinity of a heat exchanger such as an
evaporator for use in car air-conditioners according to an
embodiment of the present invention, FIG. 2 is an enlarged
cross-sectional view showing the louver fin applied to the heat
exchanger of the aforementioned embodiment, and FIG. 3 is an
enlarged cross-sectional view of the front portions of the fins of
the heat exchanger according to the aforementioned embodiment. In
the following explanation, for the purpose of facilitating the
understanding of the present invention, the explanation will be
made by assuming that the direction along the air introduction
direction X with respect to the heat exchanger of the embodiment is
a front-and-rear direction of the heat exchanger.
[0125] As shown in these figures, in this heat exchanger, a
plurality of flat heat exchanging tubes 1 and 2 each extending in
the direction perpendicular to the air introduction direction X
(i.e., the up-and-down direction) are arranged in parallel with
each other at certain intervals along the right-and-left direction
of the heat exchanger in two rows. Disposed between the adjacent
heat exchanging tubes 1 and 1 (2 and 2) arranged in the widthwise
direction of the heat exchanger is a corrugated fin 3.
[0126] The corrugated fin 3 is provided with a plurality of thin
louver fins 4 as heat transfer plates extending in the
front-and-rear direction and arranged in the up-and-down direction
at certain intervals with their sides connected alternatively to
thereby form a meandering shape. Between the adjacent louver fins 4
of the corrugated fin 3, an air passage 6 extending in the
front-and-rear direction is formed, so that the air A as heat
medium will be introduced into each air passage 6 from the front
side of the heat exchanger during the operation.
[0127] Each louver fin 4 is provided with a plurality of louvers 5
formed by cutting and bending a certain region of the louver fin at
certain intervals in the front-and-rear direction. Thus, the air A
entered into the air passages 6 will be guided by the louvers 5
into the louver gaps each formed between the adjacent louvers 5, so
that heat exchanging is performed between the air A and the
refrigerant passing through the heat exchanging tubes 1 via the
fin.
[0128] In this embodiment, when the length of the louver along
which the air passes is defined as a louver width, the
aforementioned plurality of louvers 5 in each louver fin 4 includes
wide louvers 5a each having a large louver width and narrow louvers
5b each having a small louver width, and the wide louver and the
narrow louver are disposed alternatively.
[0129] In this embodiment, when the louver width of the wide louver
5a is represented as "Lwl," it is preferable to set the width Lwl
to 0.8 to 1.3 mm. It is more preferable to set the lower limit to
0.85 mm or more and the upper limit to 1.2 mm or less. Further,
when the louver width of the narrow louver 5b is represented as
"Lws," it is preferable to set the width Lws to 0.1 to 0.6 mm. It
is more preferable to set the lower limit to 0.15 mm or more.
[0130] Too small or too large louver width Lwl or Lws causes a
deterioration of the heat transfer rate of the louver fin 4 because
of the generated bypass flow of the air or the increased pressure
loss, resulting in deteriorated heat exchanging performance.
[0131] Furthermore, in this embodiment, it is preferable to set the
ratio Lws/Lwl of the louver width "Lws" of the narrow louver 5b to
the louver width Lwl of the wide louver 5a to 0.1 to 0.7. It is
more preferable to set the lower limit to 0.3 or more.
[0132] As will be apparent from Examples which will be mentioned
later, too small or too large louver width ratio Lws/Lwl causes a
deterioration of the heat transfer rate of the louver fin 4 because
of the generated bypass flow of the air or the increased pressure
loss, resulting in deteriorated heat exchanging performance.
[0133] Furthermore, in this embodiment, the angle La of each louver
5 (louver angle) with respect to the louver fin 4 as a heat
transfer plate is set to be almost constant. It is preferable to
set the louver angle La to 22 to 36.degree.. More preferably, the
lower limit and the upper limit are set to 24.degree. or more and
32.degree. or less, respectively.
[0134] Too small or too large louver angle La causes a
deterioration of the heat transfer rate of the louver fin because
of the generated bypass flow of the air or the increased pressure
loss, resulting in deteriorated heat exchanging performance.
[0135] Furthermore, in this embodiment, the distance between the
adjacent louver fins 4 and 4, i.e., the fin pitch Fp, is preferably
set to 1 to 2 mm. More preferably, the upper limit is set to 1.6 mm
or less.
[0136] As will be apparent from Examples which will be mentioned
later, too small or too large fin pitch Fp causes a deterioration
of the heat transfer rate of the louver fin 4 because of the
generated bypass flow of the air or the increased pressure loss,
resulting in deteriorated heat exchanging performance.
[0137] Furthermore, in this embodiment, the ratio Fp/Lwl of the fin
pitch Fp to the louver width Lwl of the wide louver 5a is
preferably set to 1 or more. If this ratio is too small or too
large, the heat transfer rate may deteriorate because of the
generated bypass flow of the air or the increased pressure loss,
resulting in deteriorated heat exchanging performance.
[0138] In this invention, in cases where the plurality of louvers 5
include three or more kinds of louvers different in width, it is
preferable to set the ratio Fp/Lwmax of the fin pitch Fp to the
widest louver width Lwmax to 1 or more in the same manner as
mentioned above.
[0139] In the heat exchanger of this embodiment, since the
plurality of louvers 5 of each louver fin 4 include wide louvers 5a
and narrow louvers 5b arranged alternatively, the air A entered
into the air passages 6 will be guided by the louvers 5 into the
louver gaps each formed between the adjacent louvers 5, thereby
causing the air A to smoothly flow along each louver 5. This
improves the heat transfer rate by preventing the generation of
bypass flow of the air A, resulting in excellent heat exchanging
performance.
[0140] In the aforementioned embodiment, although the plurality of
louvers 5 of each louver fin 4 include two kinds of louvers, wide
louvers 5a and narrow louvers 5b, arranged alternatively, in the
present invention, the kind of louver or the arrangement thereof
are not limited to the above. For example, the plurality of louvers
may include one or plural wide louvers and one or plural narrow
louvers arranged alternatively. In short, the present invention
covers various embodiments so long as the plurality of louvers
include two or more kinds of louvers different in louver width
arranged in a mixed manner. For example, it can be constituted such
that the wide louvers 5a are arranged at the windward side and the
narrow louvers 5b are arranged at the leeward side as shown in FIG.
4(a); the narrow louvers 5b are arranged between the wide louvers
5a as shown in FIG. 4(b); one or more narrow louvers 5b and one or
more wide louvers 5a are arranged alternatively as shown in FIGS.
4(c) to 4(e); and the wide louvers 5a and the narrow louvers 5b are
arranged randomly.
[0141] In the aforementioned embodiments, although the explanation
is directed to the case in which the present invention is applied
to a heat exchanger such as an evaporator, the present invention is
not limited to it, but can also be applied to a heat exchanger such
as a condenser or a heater core. Furthermore, the heat exchanger is
not limited to a heat exchanger for use in car air-conditioners,
but can be used as a heat exchanger for use in room
air-conditioners, refrigerators, another refrigeration apparatuses
or heaters.
[0142] Furthermore, in the aforementioned embodiments, although the
explanation is directed to the case in which the present invention
is applied to corrugated fins, the present invention is not limited
to it, but can also be applied to plate fins in which adjacent heat
transfer fins are disposed independently.
[0143] Furthermore, in the aforementioned embodiment, although the
explanation is directed to the case in which the present invention
is applied to a fin for transferring heat by air, the present
invention is not limited to it, but can be applied to a fin for
transferring heat by heat medium other than air.
EXAMPLES
[0144] Hereinafter, Examples related to the present invention and
Comparative Examples which deviate from the gist of the present
invention will be explained.
[0145] In accordance with the aforementioned embodiment,
evaporators for car air-conditioners in which corrugated fins with
different kinds of louvers were arranged between the adjacent flat
heat exchanging tubes were examined.
Examples 1 to 5
[0146] TABLE-US-00001 TABLE 1 Lwl (mm) Lws (mm) Lws/Lwl Fp (mm) La
(.degree.) Example 1 1.1 0.167 0.152 1.3 26 Example 2 1.0 0.333
0.333 1.3 26 Example 3 1.0 0.50 0.50 1.3 26 Example 4 0.85 0.583
0.686 1.3 26 Example 5 0.85 0.65 0.765 1.3 26 Comparative 0.75 0.75
1.0 1.3 26 Example 1 Lwl: width of wide louver (mm) Lws: width of
narrow louver (mm) Lws/Lwl: louver width ratio Fp: fin pitch (mm)
La: louver angle (.degree.)
[0147] In Table 1, the evaporator of Example 1 was provided with
corrugated fins having a plurality of louver fins each including
wide louvers and narrow louvers arranged alternatively. The louver
width Lwl of the wide louver was 1.1 mm, the louver width Lws of
the narrow louver was 0.167 mm, the louver angle La was 26.degree.,
the fin pitch Fp was 1.3 mm and the louver width ratio Lws/Lwl was
0.152.
[0148] In the evaporator of Example 2, the louver width Lwl of the
wide louver was set to 1.0 mm, and the louver width Lws of the
narrow louver was set to 0.333 mm. The remaining dimensions were
set to the same as those in Example 1. The louver width ratio
Lws/Lwl was 0.333.
[0149] In the evaporator of Example 3, the louver width Lwl of the
wide louver was set to 1.0 mm, and the louver width Lws of the
narrow louver was set to 0.5 mm. The remaining dimensions were set
to the same as those in Example 1. The louver width ratio Lws/Lwl
was 0.50.
[0150] In the evaporator of Example 4, the louver width. Lwl of the
wide louver was set to 0.85 mm, and the louver width Lws of the
narrow louver was set to 0.583 mm. The remaining dimensions were
set to the same as those in Example 1. The louver width ratio
Lws/Lwl was 0.686.
[0151] In the evaporator of Example 5, the louver width Lwl of the
wide louver was set to 0.85 mm, and the louver width Lws of the
narrow louver was set to 0.65 mm. The remaining dimensions were set
to the same as those in Example 1. The louver width ratio Lws/Lwl
was 0.765.
[0152] In the evaporator of Comparative Example 1, the corrugated
fin had a plurality of louvers arranged at a constant louver width
(louver pitch) of 0.75 mm. The remaining dimensions were set to the
same as those in Example 1.
[0153] Regarding the aforementioned evaporators, each heat transfer
rate with respect to the front wind velocity was measured by
computer simulation. The results are shown in the graph of FIG.
5.
[0154] As will be apparent from the graph, the evaporators of
Examples 1 to 5 were higher than the evaporator of Comparative
Example 1 in heat transfer rate by 10 to 20% at the entire front
wind velocity region, and therefore excellent in heat exchanging
performance. Especially in the state of low speed driving state
whose front wind velocity was 2 m/s or less or the idling state,
the heat transfer rate was excellent.
[0155] Furthermore, the evaporator of Example 1 was higher than the
evaporator of Example 2 in heat transfer rate.
[0156] Among Examples 1 to 5, in each of Examples 1 to 4 in which
the ratio Lws/Lwl of the louver width Lws of the narrow louver to
the louver width Lwl of the wide louver was 0.1 to 0.7, the heat
transfer rate was more stabilized than that of Example 5 in which
the louver width ratio Lws/Lwl exceeded 0.7. Among other things, in
each of Examples 2 to 4 in which the louver width ratio Lws/Lwl was
0.3 to 0.7, sufficient heat transfer rate was obtained at the
entire front wind velocity region.
Examples 6, 7
[0157] TABLE-US-00002 TABLE 2 Lwl (mm) Lws (mm) Lws/Lwl Fp (mm) La
(.degree.) Example 6 1.0 0.333 0.333 1.3 28 Example 7 1.0 0.50 0.50
1.3 28 Comparative 0.75 0.75 1.0 1.3 28 Example 2 Lwl: width of
wide louver (mm) Lws: width of narrow louver (mm) Lws/Lwl: louver
width ratio Fp: fin pitch (mm) La: louver angle (.degree.)
[0158] As shown in Table 2, the evaporator of Example 6 was
prepared in the same manner as the aforementioned Example 2 except
that the louver angle La was set to 28.degree..
[0159] The evaporator of Example 7 was prepared in the same manner
as the aforementioned Example 3 except that the louver angle La was
set to 28.degree..
[0160] The evaporator of Comparative Example 2 was prepared in the
same manner as the aforementioned Comparative Example 1 except that
the louver angle La was set to 28.degree..
[0161] Regarding the aforementioned evaporators, each heat transfer
rate with respect to the front wind velocity was measured by
computer simulation. The results are shown in the graph of FIG.
6.
[0162] As will be apparent from the graph, even in the case in
which the louver angle La is set to 28.degree., the evaporators of
Examples 6 and 7 were higher than the evaporator of Comparative
Example 2 in heat transfer rate at the entire front wind velocity
region, and therefore excellent in heat exchanging performance.
Especially in the state of low speed driving state whose front wind
velocity was 2 m/s or less or the idling state, the heat transfer
rate was high.
Examples 8, 9
[0163] TABLE-US-00003 TABLE 3 Lwl (mm) Lws (mm) Lws/Lwl Fp (mm) La
(.degree.) Example 8 1.0 0.333 0.333 1.3 -- Example 9 1.0 0.50 0.50
1.3 -- Comparative 0.75 0.75 1.0 1.3 -- Example 3 Lwl: width of
wide louver (mm) Lws: width of narrow louver (mm) Lws/Lwl: louver
width ratio Fp: fin pitch (mm) La: louver angle (.degree.)
[0164] Evaporators of Examples 8 and 9 and Comparative Example 3
were prepared in the same manner as in the aforementioned Examples
2 and 3 and Comparative Example 1 except that the louver angle La
was set to parameter.
[0165] In each of these evaporators, each heat transfer rate with
respect to the louver angle La in the state in which the front wind
velocity was 1 m/s and 2 m/s was measured by computer simulation.
These results are shown in the graphs of FIGS. 7 and 8.
[0166] As will be apparent from both graphs, in the case where the
air velocity was 1 m/s, as compared with the evaporator of
Comparative Example 3, the evaporators of Examples 8 and 9 were
extremely higher in thermal transfer coefficient at the louver
angle 17 to 36.degree., and slightly higher at the louver angle
exceeding 36.degree.. Furthermore, in the case where the air
velocity was 2 m/s, the heat transfer rate of each of Examples 8
and 9 was higher at the louver angle of 17 to 31.degree.. To the
contrary, in the case where the louver angle exceeds 30.degree.,
significant difference could not be recognized between Examples and
Comparative Example.
[0167] As shown in FIG. 7, in the idling state (in the state of the
front wind velocity of 1 m/s) in which it is difficult to attain
high performance, in the evaporators of Examples 8 and 9, high heat
transfer rate could be obtained at the louver angle La of 22 to
36.degree.. In the case where the lower limit was 24.degree. or
more and the upper limit was 32.degree. or less, higher heat
transfer rate could be obtained.
[0168] Furthermore, as shown in FIG. 8, in the case where the front
wind velocity of 2 m/s, high heat transfer rate could be obtained
at the louver angle La of 20 to 30.degree.. In the case where the
lower limit was 22.degree. or more and the upper limit was
28.degree. or less, higher heat transfer rate could be
obtained.
Examples 10 and 11
[0169] TABLE-US-00004 TABLE 4 Lwl (mm) Lws (mm) Lws/Lwl Fp (mm) La
(.degree.) Example 10 1.0 0.333 0.333 -- 26 Example 11 1.0 0.50
0.50 -- 26 Comparative 0.75 0.75 1.0 -- 26 Example 4 Lwl: width of
wide louver (mm) Lws: width of narrow louver (mm) Lws/Lwl: louver
width ratio Fp: fin pitch (mm) La: louver angle (.degree.)
[0170] As shown in Table 4, evaporators of Examples 10 and 11 and
Comparative Example 4 were prepared in the same manner as in the
aforementioned Examples 2 and 3 and Comparative Example 1 except
that the fin pitch Fp was set to parameter.
[0171] In each of these evaporators, each heat transfer rate with
respect to the fin pitch Fp in the state where the front wind
velocity was 1 m/s and 2 m/s was measured by computer simulation.
These results are shown in the graphs of FIGS. 9 and 10.
[0172] As will be apparent from both graphs, in the case where the
air velocity was 1 m/s and 2 m/s, as compared with the evaporator
of Comparative Example 4, the evaporators of Examples 10 and 11
were extremely higher in heat transfer rate at the fin pitch Fp of
1.0 to 2.4 mm.
[0173] Especially, in the evaporators of Examples 10 and 11, in the
case where the fin pitch Fp was 1.6 mm or less, sufficient heat
transfer rate was obtained.
[0174] In the heat exchanger fin according to the invention, since
a plurality of louvers include plural kinds of louvers different in
louver width, the heat medium such as air will be assuredly
introduced into the lower gaps each formed between adjacent louvers
to flow smoothly along each louver, resulting in improved heat
transfer rate by preventing generation of bypass flow.
[0175] The terms and expressions which have been employed herein
are used as terms of description and not of limitation, and there
is no intent, in the use of such terms and expressions, of
excluding any of the equivalents of the features shown and
described or portions thereof, but it is recognized that various
modifications are possible within the scope of the invention
claimed.
INDUSTRIAL APPLICABILITY
[0176] The present invention can be applied to a heat exchanger
such as a car air-conditioning condenser or evaporator, and also to
a heat exchanger fin such as a louver fin or a corrugated fin to be
equipped to the heat exchanger.
* * * * *