U.S. patent application number 11/488106 was filed with the patent office on 2008-01-17 for dual flow heat exchanger header.
This patent application is currently assigned to Advanced Distributor Products LLC. Invention is credited to John L. Bauer, Colby W. Logan, James W. Pickle, James F. Timbs.
Application Number | 20080011463 11/488106 |
Document ID | / |
Family ID | 38948080 |
Filed Date | 2008-01-17 |
United States Patent
Application |
20080011463 |
Kind Code |
A1 |
Timbs; James F. ; et
al. |
January 17, 2008 |
Dual flow heat exchanger header
Abstract
An A-coil heat exchanger includes a header for receiving a heat
transfer fluid after the fluid has passed through the interior of
the heat exchanger. The header is comprised of a main body section
and first and second tubular branches depending therefrom. The
first tubular branch is in fluid communication with a first coil
slab of the heat exchanger by means of a first set of adapter tubes
extending between the first tubular section and the first coil
slab. The second tubular branch is in fluid communication with a
second coil slab of the heat exchanger by means of a second set of
adapter tubes extending between the second tubular branch and the
second coil slab. Each of the adapter tubes defines a generally
straight section of conduit between the corresponding tubular
branch and the corresponding coil slab. The header is located with
respect to the coil slabs such that when the heat exchanger is
positioned in an air stream, the header is substantially isolated
from air flowing through the first and second coil slabs.
Inventors: |
Timbs; James F.; (Winona,
MS) ; Pickle; James W.; (Grenada, MS) ; Logan;
Colby W.; (Grenada, MS) ; Bauer; John L.;
(Grenada, MS) |
Correspondence
Address: |
W. Kirk McCord, Esq.;Intellectual Property Counsel
Lennox International Inc., P. O. Box 799900
Dallas
TX
75379-9900
US
|
Assignee: |
Advanced Distributor Products
LLC
|
Family ID: |
38948080 |
Appl. No.: |
11/488106 |
Filed: |
July 17, 2006 |
Current U.S.
Class: |
165/151 |
Current CPC
Class: |
F28F 9/02 20130101; F28F
9/0275 20130101; F28D 2001/0266 20130101; F28D 1/0477 20130101 |
Class at
Publication: |
165/151 |
International
Class: |
F28D 1/04 20060101
F28D001/04 |
Claims
1. In a heat exchanger having first and second coil slabs coupled
at respective ends thereof and being in diverging relationship to
define an A-coil configuration, each of said slabs having at least
one heat transfer carrying tube, wherein the improvement comprises
a header adapted to receive heat transfer fluid from said slabs,
said header having a main section and first and second branch
sections depending therefrom, said first branch section being in
fluid communication with said first coil slab and said second
branch section being in fluid communication with said second coil
slab.
2. The heat exchanger of claim 1 further including a first conduit
in fluid communication between said first branch section and said
first coil slab and a second conduit in fluid communication between
said second branch section and said second coil slab.
3. The heat exchanger of claim 2 wherein said first conduit defines
a generally straight section of conduit between said first branch
section and said first coil slab and said second conduit defines a
generally straight section of conduit between said second branch
section and said second coil slab.
4. The heat exchanger of claim 2 further including plural first
conduits in fluid communication between said first branch section
and said first coil slab and plural second conduits in fluid
communication between said second branch section and said second
coil slab.
5. The heat exchanger of claim 2 wherein said first conduit extends
from said first branch section in a first direction and said second
conduit extends from said second branch section in a second
direction which is in divergent relationship to said first
direction.
6. The heat exchanger of claim 1 wherein said first and second
branch sections are in generally parallel relationship.
7. The heat exchanger of claim 6 wherein said main section and said
first and second branch sections extend generally parallel to an
axis along which said first and second coil slabs are coupled.
8. The heat exchanger of claim 1 wherein said heat exchanger is
positionable for horizontal air flow therethrough, said main
section and said first and second branch sections having respective
major axes that are in parallel relationship, said respective major
axes being oriented vertically when said heat exchanger is
positioned for horizontal air flow therethrough.
9. The heat exchanger of claim 1 wherein said header is located
proximate to the coupled ends of said first and second coil slabs
such that when said heat exchanger is positioned in an air stream,
said header is substantially isolated from air flowing through said
first and second coil slabs.
10. A header adapted for connection to an A-coil heat exchanger to
receive heat transfer fluid therefrom, said header comprising a
main section and first and second branch sections depending
therefrom, said first branch section being adapted to receive heat
transfer fluid from a first portion of the heat exchanger and said
second branch section being adapted to receive heat transfer fluid
from a second portion of the heat exchanger.
11. The header of claim 10 further including at least one first
conduit extending from said first branch section and being adapted
to feed heat transfer fluid from the first portion of the heat
exchanger to said first branch section, said header further
including at least one second conduit extending from said second
branch section and being adapted to feed heat transfer fluid from
the second portion of the heat exchanger to said second branch
section.
12. The header of claim 11 wherein said first conduit defines a
generally straight first section of conduit and said second conduit
defines a generally straight second section of conduit.
13. The header of claim 11 further including plural first conduits
extending from said first branch section and plural second conduits
extending from said second branch section.
14. The header of claim 11 wherein said first conduit extends from
said first branch section in a first direction and said second
conduit extends from said second branch section in a second
direction which is in divergent relationship to said first
direction.
15. The header of claim 10 wherein said first and second branch
sections are in generally parallel relationship.
16. The header of claim 15 wherein said main section and said first
and second branch sections each have a major axis and a minor axis,
the respective major axes of said main section and said first and
second branch sections being in generally parallel
relationship.
17. In combination: a heat exchanger having first and second coil
slabs coupled at respective ends thereof and being in diverging
relationship to define an A-coil configuration, each of said slabs
having a passageway adapted for heat transfer fluid to pass
therethrough; and a header in fluid communication with said slabs
to receive heat transfer fluid after the fluid has passed through
said slabs, said header having a main body section and first and
second tubular branches depending therefrom, said first tubular
branch being in fluid communication with said first coil slab and
said second tubular branch being in fluid communication with said
second coil slab, said header being located proximate to the
coupled ends of said first and second coil slabs such that when
said heat exchanger is positioned in an air stream, said header is
substantially isolated from air flowing through said first and
second coil slabs.
18. The combination of claim 17 further including plural first
conduits in fluid communication between said first tubular branch
and said first coil slab and plural second conduits in fluid
communication between said second tubular branch and said second
coil slab.
19. The combination of claim 18 wherein said each of first conduits
defines a generally straight section of conduit between said first
tubular branch and said first coil slab and each of said second
conduits defines a generally straight section of conduit between
said second tubular branch and said second coil slab.
20. The combination of claim 19 wherein said first conduits extend
from said first tubular branch section in respective first
directions and said second conduits extend from said second tubular
branch in respective second directions which are in divergent
relationship to said respective first directions.
Description
TECHNICAL FIELD
[0001] This invention relates generally to heat exchangers used in
air conditioning and refrigeration applications and in particular
to heat exchangers of the A-coil type.
BACKGROUND ART
[0002] Heat exchangers are widely used in a variety of applications
in the fields of air conditioning, refrigeration and the like.
Typically, such heat exchangers are comprised of plural rows of
tubes in which a first heat transfer fluid, such as water or a
vapor compression refrigerant, flows while a second heat transfer
fluid, such as air, is directed across the outside of the tubes. To
improve heat transfer, a plurality of fins comprising thin sheets
of metal are used. Each fin has multiple holes through which the
tubes are laced and the fins are arranged in parallel, closely
spaced relationship along the tubes to define multiple paths for
the second heat transfer fluid to flow across the fins and around
the tubes.
[0003] One type of heat exchanger often used in air conditioning
and refrigeration applications is the so-called "A-coil" heat
exchanger, an example of which is shown in FIG. 1. Referring now to
FIG. 1, heat exchanger 10 is comprised of a pair of coil slabs 12,
14, which are coupled together at respective ends thereof by a
connector plate 16 and are in divergent relationship to define a
generally "A" shape. Each slab 12, 14 has plural tubes 18 laced
through a plurality of fins 20. Tubes 18 are adapted to allow
passage of a first heat transfer fluid (e.g., a vapor compression
refrigerant) therethrough. Fins 20 are in parallel, closely spaced
relationship and cooperate with tubes 18 to provide multiple paths
for a second heat transfer fluid (e.g., air to be cooled) to flow
across heat exchanger 10 on the outside of tubes 18.
[0004] Four rows of tubes 18 (two rows on each slab 12, 14) are
shown in FIG. 1, by way of example. In other embodiments of an
A-coil heat exchanger, the number of tube rows may be greater or
less than two. Each tube row defines a discrete fluid circuit, with
each circuit comprising multiple passes through the corresponding
slab 12, 14. Return bends 22 connect distal ends of adjacent tubes
18. Tubes 18 penetrate through end plates 24 at the opposed ends of
each slab 12, 14. Only one end plate 24 is shown on each slab 12,
14 in FIG. 1.
[0005] Four adapter tubes 26 connect the outlets of the respective
tube circuits to an outlet header 28 in fluid communication with
the suction side of a compressor (not shown) when heat exchanger 10
is used in a vapor compression air conditioning or refrigeration
system. Header 28 extends horizontally across heat exchanger 10
proximate to the coupled ends of slabs 12, 14, and then bends
upwardly at an approximately 90.degree. angle. Although not shown
in FIG. 1, plural distributor tubes connect the inlets of the
respective tube circuits to an inlet header in fluid communication
with the discharge side of the compressor. A drain pan (not shown)
is preferably positioned under heat exchanger 10 to collect
condensate runoff.
[0006] In operation, when heat exchanger 10 is used as an
evaporator, the refrigerant enters heat exchanger 10 through the
distributor tubes in substantially liquid form, makes multiple
passes through heat exchanger 10 in each tube circuit, is
substantially vaporized in heat exchanger 10 and exits heat
exchanger 10 through adapter tubes 26. Further, when heat exchanger
10 is oriented in a "horizontal coil" configuration, as shown in
FIG. 1, air or other fluid to be cooled flows horizontally into the
region between slabs 12, 14 and horizontally outwardly through both
slabs 12, 14, as indicated by arrows 29, whereby the air or other
fluid is cooled. Header 28 is located such that the vertical
portion thereof is in the air stream flowing outwardly from slab
12. Further, adapter tubes 26 are configured with multiple bends to
enable adapter tubes 26 to be connected to selected ones of tubes
18.
SUMMARY OF THE INVENTION
[0007] In accordance with the present invention, a heat exchanger
of the A-coil type having first and second coil slabs coupled at
respective ends thereof and being in divergent relationship
includes a header adapted to receive heat transfer fluid from the
slabs. The header has a main section and first and second tubular
branches sections depending therefrom. The first branch is in fluid
communication with the first coil slab and the second branch is in
fluid communication with the second coil slab.
[0008] In accordance with one embodiment of the invention, the heat
exchanger further includes a first conduit in fluid communication
between the first branch and the first coil slab and a second
conduit in fluid communication between the second branch and the
second coil slab.
[0009] In accordance with another embodiment of the invention, the
first conduit defines a generally straight section of conduit
between the first branch and the first coil slab and the second
conduit defines a generally straight section of conduit between the
second branch section and the second coil slab.
[0010] In accordance with yet another embodiment of the invention,
the first conduit extends from the first branch in a first
direction and the second conduit extends from the second branch in
a second direction which is in divergent relationship to the first
direction.
[0011] In accordance with still another embodiment of the
invention, the header is located with respect to the first and
second coil slabs such that when the heat exchanger is positioned
in an air stream, the header is substantially isolated from air
flowing through the first and second coil slabs.
[0012] In accordance with a preferred embodiment of the invention,
the heat exchanger includes plural first conduits in fluid
communication between the first branch and the first coil slab and
plural second conduits in fluid communication between the second
branch and the second coil slab. The first and second branches are
in generally parallel relationship and extend generally parallel to
an axis along which the first and second coil slabs are
coupled.
BRIEF DESCRIPTION OF DRAWINGS
[0013] FIG. 1 is a perspective view of a prior art A-coil heat
exchanger;
[0014] FIG. 2 is a perspective view of an A-coil heat exchanger in
accordance with an embodiment of the present invention;
[0015] FIG. 3 is an end elevation view of the A-coil heat exchanger
of FIG. 2;
[0016] FIG. 4 is a side elevation view of the A-coil heat exchanger
of FIG. 2;
[0017] FIG. 5 is a top plan view of the A-coil heat exchanger of
FIG. 2; and
[0018] FIG. 6 is a perspective view of a header component used in
the heat exchanger of FIG. 2.
BEST MODE FOR CARRYING OUT THE INVENTION
[0019] The best mode for carrying out the invention will now be
described with reference to the accompanying drawings. Like parts
are marked in the specification and drawings with the same
respective reference numbers. In some instances, proportions may
have been exaggerated in order to depict certain features of the
invention.
[0020] Referring now to FIGS. 2-6, an A-coil heat exchanger 30 is
comprised of first and second coil slabs 32, 34 that are coupled
together at respective ends thereof by a connector plate 36 and are
in divergent relationship to define a generally "A" shape. Each
slab 32, 34 has plural heat transfer fluid carrying tubes 38, which
are laced through a plurality of fins 40. Tubes 38 each have an
internal passageway to accommodate the flow of a first heat
transfer fluid (e.g., a vapor compression refrigerant)
therethrough. Fins 40 are in parallel, closely spaced relationship
and cooperate with tubes 38 to provide multiple paths for a second
heat transfer fluid (e.g., air to be cooled) to flow across heat
exchanger 30 on the outside of tubes 38. Heat is transferred from
the second heat transfer fluid to the first heat transfer
fluid.
[0021] Four rows of tubes 38 (two rows on each slab 32,34) are
shown in FIG. 1, by way of example. One skilled in the art will
recognize that the number of tube rows may be greater or less than
two. Each tube row defines a discrete fluid circuit, with each
circuit comprising multiple passes through the corresponding slab
32, 34. Return bends 42 connect distal ends of adjacent tubes 38.
Tubes 38 penetrate through end plates 44 at the opposed ends of
each slab 32,34. Only one end plate 44 is shown on each slab 32, 34
in FIG. 1.
[0022] As will be described in greater detail hereinbelow, a first
pair of adapter tubes 46 and a second pair of adapter tubes 47
connect the outlets of the respective tube circuits to an outlet
header 48 in fluid communication with the suction side of a
compressor (not shown) when heat exchanger 30 is used in a vapor
compression air conditioning or refrigeration system. When heat
exchanger 30 is oriented for horizontal air flow, as shown in FIGS.
2-5, slabs 32, 34 are coupled together by connector plate 36 along
a vertical axis. Header 48 is positioned with respect to the
coupled ends of slabs 32, 34, such that no portion of header 48
would be located in a horizontal air stream flowing through slabs
32,34. Although not shown in FIGS. 2-5, heat exchanger 30 also
includes plural distributor tubes connecting the inlets of the
respective tube circuits to an inlet header in fluid communication
with the discharge side of the compressor. A drain pan (not shown)
is preferably positioned under heat exchanger 30 to collect
condensate runoff.
[0023] In operation, when heat exchanger 30 is used as an
evaporator, the refrigerant enters heat exchanger 30 through the
distributor tubes in substantially liquid form, makes multiple
passes through heat exchanger 30 in each tube circuit, is
substantially vaporized in heat exchanger 30 and exits heat
exchanger 30 through adapter tubes 46, 47. Further, when heat
exchanger 30 is oriented in a "horizontal coil" configuration, as
shown in FIGS. 2-5, air or other fluid to be cooled flows
horizontally into the region between slabs 32, 34 and horizontally
outwardly through both slabs 32, 34, as indicated by arrows 49,
whereby the air or other fluid is cooled.
[0024] As can be best seen in FIG. 6, header 48 defines the general
shape of a two-pronged fork and is comprised of a main body section
50 and first and second tubular branches 52, 54 depending
therefrom. Branches 52, 54 are in parallel relationship. Respective
major axes of main body section 50 and tubular branches 52, 54 are
oriented along respective vertical axes parallel to the vertical
axis along which slabs 32,34 are coupled together. Main body
section 50 has a flared open end 50a, which is adapted to connect
header 48 to a compressor suction line (not shown). An opposite end
of main body section 50 is defined by a bulbous portion 50b
containing first and second sockets (not shown) in which respective
open ends of first and second tubular branches 52,54 are received.
The respective opposite ends of tubular branches 52, 54 are closed.
First tubular branch 52 is in fluid communication with first coil
slab 32 by means of adapter tubes 46, which extend horizontally
outwardly from first tubular branch 52 along respective axes that
are perpendicular to the major axis of first tubular branch 52.
Second tubular branch 54 is in fluid communication with second coil
slab 34 by means of adapter tubes 47, which extend horizontally
outwardly from second tubular branch 54 along respective axes that
are perpendicular to the major axis of second tubular branch
54.
[0025] Adapter tubes 46 are in divergent relationship with respect
to adapter tubes 47, corresponding to the divergent relationship
between slabs 32 and 34. Further, the two tubes 46 are stacked
vertically one above the other and the two tubes 47 are stacked
vertically one above the other, so that each adapter tube 46, 47
defines a generally straight section of conduit between the
corresponding tubular branch 52, 54 and the corresponding coil slab
32, 34. One skilled in the art will recognize that the
aforementioned configuration of adapter tubes 46,47 eliminates the
need for one or more bends in the adapter tubes characterized by
prior art A-coil heat exchangers.
[0026] As can be best seen in FIG. 3, main body section 50 and
first and second branches 52,54 are oriented vertically and extend
generally parallel to a vertical axis along which first and second
coil slabs 32, 34 are coupled by connector plate 36. Header 48 is
located with respect to coil slabs 32, 34 such that when heat
exchanger 30 is positioned in a horizontal air stream, header 48 is
substantially isolated from air flowing through first and second
coil slabs 32, 34.
[0027] The best mode for carrying out the invention has now been
described in detail. Since changes in and modifications to the
above-described preferred embodiment may be made without departing
from the nature, spirit and scope of the invention, the invention
is not to be limited to said details, but only by the appended
claims and their equivalents.
* * * * *