U.S. patent application number 10/879310 was filed with the patent office on 2006-01-12 for heat exchanger with bypass seal.
Invention is credited to Keith D. Agee, Richard P. Beldam, Steven Broadbent, Roland L. Dilley, Willi J. Smith.
Application Number | 20060005940 10/879310 |
Document ID | / |
Family ID | 35094613 |
Filed Date | 2006-01-12 |
United States Patent
Application |
20060005940 |
Kind Code |
A1 |
Dilley; Roland L. ; et
al. |
January 12, 2006 |
Heat exchanger with bypass seal
Abstract
A heat exchanger includes a core with a plurality of passages
arranged therein each having an opening positioned adjacent an end
portion of the core. A manifold is positioned adjacent the core end
portion and includes an inlet and an outlet opening. The manifold
includes a divider wall that extends internally therein and that
forms separated inlet and outlet passages that are in communication
with the respective inlet and outlet openings. The heat exchanger
includes a metallic seal interposed between the divider wall and
the core to provide a seal therebetween. The seal is constructed to
impose a biasing force between the divider wall and the core to
provide the desired seal, thereby minimizing or eliminating any
unwanted bypass of fluid or gas within the manifold during heat
exchanger operation and increasing heat exchanger operating
efficiency.
Inventors: |
Dilley; Roland L.; (Lomita,
CA) ; Agee; Keith D.; (Torrance, CA) ; Beldam;
Richard P.; (Torrance, CA) ; Smith; Willi J.;
(Torrance, CA) ; Broadbent; Steven; (Harbor City,
CA) |
Correspondence
Address: |
Ephraim Starr, Division General Counsel;Honeywell International Inc.
Suite #200
23326 Hawthorne Boulevard
Torrance
CA
90505
US
|
Family ID: |
35094613 |
Appl. No.: |
10/879310 |
Filed: |
June 28, 2004 |
Current U.S.
Class: |
165/9 |
Current CPC
Class: |
F28F 9/005 20130101;
F28F 9/0202 20130101; F28D 7/1607 20130101; F28D 21/0003
20130101 |
Class at
Publication: |
165/009 |
International
Class: |
F23L 15/02 20060101
F23L015/02 |
Claims
1. A heat exchanger comprising; a core comprising a plurality of
passages arranged therein for providing multi-pass flow of gas or
fluid therein, the plurality of passages each having openings
positioned adjacent an end portion of the core; a manifold adjacent
the core and including a gas or fluid inlet and a gas or fluid
outlet, the manifold including a divider wall extending therein
forming a gas or fluid inlet passage in communication with the gas
or fluid inlet that is separated from a gas or fluid outlet passage
in communication with the gas or fluid outlet; and a metallic seal
interposed between the divider wall and the core.
2. The heat exchanger as recited in claim 1 wherein the seal is
configured having a first portion in contact with the divider wall,
and a second portion in contact with the core, the first and second
portions being integral with one another.
3. The heat exchanger as recited in claim 2 wherein the first
portion is in contact with the divider wall, and the second portion
is biased against the core.
4. The heat exchanger as recited in claim 3 wherein the second
portion departs from the first portion at an angle of departure of
less than about 180 degrees.
5. The heat exchanger as recited in claim 2 wherein the first
portion is a groove and an end of the divider wall is disposed
therein.
6. The heat exchanger as recited in claim 5 wherein the seal
includes ridges on each side of the groove, and further includes a
base that contacts the core and that is common to each of the
ridges.
7. The heat exchanger as recited in claim 6 wherein the seal
comprises a one-piece construction.
8. The heat exchanger as recited in claim 5 wherein the seal
includes a pair of legs extending from the groove that contact
respective opposite surfaces of the divider wall, and wherein the
groove outside surface defines a base portion that contacts the
core.
9. The heat exchanger as recited claim 8 wherein the legs are each
attached to the respective surfaces of the divider wall.
10. The heat exchanger as recited in claim 8 wherein the seal
comprises a one-piece construction.
11. A heat exchanger comprising: a shell having an internal chamber
defined by an open end and a closed end; a core disposed within the
shell and comprising a plurality of passages arranged therein, the
passages including openings positioned adjacent an end of the core;
a manifold connected to the shell open end and positioned adjacent
the end of the core, the manifold including an inlet and an outlet,
the manifold including a divider wall defining separate inlet and
outlet passages in communication with a respective inlet and
outlet; and a metallic seal interposed between the divider wall and
the core, the seal having a one-piece construction and providing a
biasing force therebetween.
12. The heat exchanger as recited in claim 11 wherein the seal
includes a first portion that is attached to the divider wall, and
a second portion that is pressed against a surface of the core, the
first and second portions being integral with one another.
13. The heat exchanger as recited in claim 12 wherein the seal
first portion and second portion are have an angle of departure
from one another of less than about 180 degrees.
14. The heat exchanger as recited in claim 11 wherein the seal
includes a groove and the divider wall includes an end that
contacts the groove.
15. (canceled)
16. The heat exchanger as recited in claim 14 further comprising a
pair of legs extending from the groove and contacting opposite
surfaces of the divider wall, the groove having an outside surface
defining a base for contacting a core surface, wherein the seal has
a "C-shaped" configuration.
17. An exhaust gas cooler comprising: a shell having an internal
chamber and having a coolant inlet and a coolant outlet for
facilitating the passage of a coolant within the chamber; a core
disposed within the shell and comprising a plurality of passages
for accommodating the passage of exhaust gas therethrough, the
passages having an outside surface that is in contact with the
coolant within the shell; a manifold connected to the shell and
positioned adjacent the core, the manifold including a divider wall
that projects towards the core and that defines inlet and outlet
passages within the manifold that are in communication with
respective portions of the core; and sealing means interposed
between the divider wall and the core to provide a seal
therebetween, the sealing means being formed from a metallic
material.
18. The cooler as recited in claim 17 wherein the sealing means is
separate from the divider wall and provides a biasing force against
the core to provide a sealing force thereagainst.
19. The cooler as recited in claim 18 wherein the sealing means
includes a first member that provides a seal against an end of the
divider wall, and a second member that provides a seal against a
section of the core adjacent the divider wall, the first and second
members being integral with one another.
20. (canceled)
21. A heat exchanger comprising: a core comprising a plurality of
passages arranged therein for providing multi-pass flow of gas or
fluid therein, the plurality of passages each having openings
positioned adjacent an end portion of the core; a manifold adjacent
the core and including a gas or fluid inlet and a gas or fluid
outlet, the manifold including a divider wall extending therein
forming a gas or fluid inlet passage in communication with the gas
or fluid inlet that is separated from a gas or fluid outlet passage
in communication with the gas or fluid outlet; and a
non-elastomeric seal interposed between the divider wall and the
core.
Description
FIELD OF INVENTION
[0001] This invention relates generally to the field of heat
exchangers and, more particularly, to heat exchangers that are
specifically configured to include a bypass seal disposed
internally therein to maintain the separation of heat exchanger
inlet and outlet flow within the heat exchanger, thereby improving
heat exchanger operation efficiency.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to heat exchangers that are
generally configured having one or more manifold members that are
constructed to receive and/or dispense a particular fluid or gas in
need of cooling, and a core member that is connected to the
manifold members to receive the fluid or gas in need of cooling by
conductive and convective heat transfer. The heat exchanger can
also include one or more manifold members constructed to receive
and/or dispense a particular cooling fluid or gas, that are placed
into contact with the core member. Such heat exchangers known in
the art can be configured having a single or multiple pass hot-side
or cold-side designs.
[0003] The core member is typically configured to provide a desired
degree of heat transfer. Generally, the core comprises a plurality
of hollow heat transfer passages that are provided in number sized
and position to permit a desired degree of fluid or gas flow
therethrough. These heat transfer passages may also be configured
having extended inside or outside surfaces that are specially
designed to promote desired heat transfer.
[0004] Referring to FIG. 1, a particular type of heat exchanger 10
known in the art is a shell and tube heat exchanger that comprises
a shell 12 or body that surrounds the core 14. For purposes of
clarity and reference, the core is illustrated with only two
passages instead of being fully loaded with a plurality of
passages. In a two-pass heat exchanger design, the manifold 16 is
attached to one end 18 of the shell and includes both an inlet
opening 20 and an outlet opening 22. This type of heat exchanger is
used in applications such as for cooling exhaust gas from an
internal combustion engine using an exhaust gas recirculation
system.
[0005] In this example, the core includes a first end 24 that is
positioned adjacent the manifold and a second end 26 that is
positioned adjacent a closed end 28 of the shell 12. The manifold
16 includes a divider wall 30 that operates to form separate inlet
and outlet passages 32 and 34 therein. Hot exhaust gas entering the
manifold inlet passes into openings in the first end 24 of the core
that are in communication with the manifold inlet passage 32, exits
the second end 26 of the core, is directed into passage openings in
the core second end that are in communication with the manifold
outlet passage 34, and is passed for a second time through the
core. As this occurs, the gas traveling through the core is cooled
by contact that is made between a cooling medium circulated within
the shell and the core. The exhaust gas then exits the core first
end 24 through passage openings that are in communication with the
manifold outlet passage, and is routed out of the heat exchanger
via the exhaust outlet opening 22.
[0006] A problem known to exist in heat exchangers configured in
the manner described above involves the existence of undesired gas
flow bypass within the heat exchanger between the gas inlet and gas
outlet streams; specifically, gas bypass that occurs within the
manifold gas inlet and gas outlet passages by virtue of a gap that
exists between the manifold divider wall and the core. Past
attempts at addressing this situation have involved the use of an
elastomeric seal between the divider wall and the core. However,
the use of such elastomeric seals have not proven effective due to
the high operating temperatures that exist within the manifold,
which can exceed 315.degree. C. metal temperature. Such internal
exhaust gas bypass is undesired as it can adversely impact heat
exchanger operating efficiency. If the divider wall is structurally
attached to the core, for example by welding or brazing,
destructive thermal stresses may arise, reducing heat exchanger
life
[0007] It is, therefore, desired that a heat exchanger be
constructed in a manner that reduces or eliminates unwanted
internal bypass of inlet and outlet gas therein. Is desired that
such heat exchanger be constructed in a manner that permits the use
of existing heat exchanger parts or elements with minimal if any
modification. It is further desired that such heat exchanger be
constructed in a manner that neither adversely impacts other heat
exchanger performance properties, nor adversely impacts
construction by using materials and methods that are readily
available to facilitate cost effective manufacturing and assembly
of the same.
SUMMARY OF THE INVENTION
[0008] Heat exchangers constructed in accordance with this
invention comprise a core having a plurality of passages arranged
therein that can be configured to provide multi-pass flow of gas or
fluid therein. The plurality of passages each have openings
positioned adjacent an end portion of the core.
[0009] A manifold is positioned adjacent the core end portion and
includes a gas or fluid inlet and a gas or fluid outlet. The
manifold further includes a divider wall that extends internally
therein forming a gas or fluid inlet passage that is in
communication with the gas or fluid inlet, and forming a gas or
fluid outlet passage that is in communication with the gas or fluid
outlet and that is separate from the inlet passage.
[0010] The heat exchanger further includes a metallic seal
interposed between the divider wall and the core end portion to
provide a seal therebetween. The metallic seal is configured to
create a biasing force between the divider wall and core when the
manifold and core are assembled together. The biasing force
operates to provide the desired seal between the manifold and core
to minimize or prevent the unwanted bypass of fluid or gas within
the manifold during heat exchanger operation, thereby increasing
heat exchanger operating efficiency.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The invention will be more clearly understood with reference
to the following drawings wherein:
[0012] FIG. 1 is a cross-sectional view of a prior art heat
exchanger;
[0013] FIG. 2 is a top view of a manifold portion of the heat
exchanger from FIG. 1;
[0014] FIG. 3 is a cross-sectional view of a manifold portion of a
heat exchanger of this invention comprising a bypass seal according
to a first invention embodiment;
[0015] FIG. 4 is a cross-sectional view of a manifold portion of a
heat exchanger of this invention comprising a bypass seal according
to a second invention embodiment;
[0016] FIG. 5 is a cross-sectional view of a manifold portion of a
heat exchanger of this invention comprising a bypass seal according
to a third invention embodiment; and
[0017] FIG. 6 is a cross-sectional view of a manifold portion of a
heat exchanger of this invention comprising a bypass seal according
to a fourth invention embodiment.
DETAILED DESCRIPTION OF THE INVENTION
[0018] The present invention relates to heat exchangers used for
reducing the temperature of an entering gas or fluid stream. The
particular application for the heat exchangers of the present
invention is with vehicles and, more particularly, to cool an
exhaust gas stream in an exhaust gas recirculation (EGR) system, or
to cool a pressurized air intake stream in a turbocharged or
supercharged engine system. However, it will be understood that
this is only an exemplary embodiment. It will be readily understood
by those skilled in the relevant technical field that the heat
exchanger configurations of the present invention described herein
can be used in a variety of applications.
[0019] Generally, the invention involves use with heat exchangers
that are similar to that described above and as illustrated in FIG.
1 having a shell and tube design.
[0020] As mentioned above, the core includes a plurality of
passages or tubes disposed therein and can be referred to as a tube
bundle. The core comprises a plurality of passage openings
positioned adjacent the shell open end 18 when the core is disposed
within the shell. The core passages positioned in communication
with the manifold inlet passage facilitate a first pass of exhaust
gas through the core, and the core passages positioned in
communication with the manifold outlet passage facilitate a second
pass of exhaust gas through the core.
[0021] The shell includes a cooling inlet port (not shown) and a
cooling outlet port 36 for circulating a desired cooling medium
within the shell that contacts the core and the plurality of
passages to reduce the temperature of the gas as it is passed
therethrough. Depending on the particular application, the cooling
inlet and outlet ports can be provided in the form of manifolds
that are attached to the shell.
[0022] Referring to FIG. 2, the manifold 16 is attached to the
shell 12 and includes inlet and outlet openings 20 and 22. The
inlet opening 20 is positioned and configured to receive gas or
fluid and direct the gas or fluid into the heat exchanger and, more
specifically, to the portion of the core passages in communication
with the manifold inlet passage 32. The outlet opening 22 is
positioned and configured to receive gas or fluid exiting the
portion of the core passages in communication with the manifold
outlet passage 34.
[0023] As illustrated, the manifold inlet opening 20 is disposed
through a top surface 38 of the manifold and is positioned within a
first portion of the manifold top surface. It is understood that
the opening may be on the side or other location of surface 38. In
such preferred embodiment, the manifold outlet opening 22 is also
disposed through the top surface 38 and is positioned along a
second portion of the manifold top surface. Additionally, as shown
in FIG. 2, diffuser vanes 40 can be positioned within the manifold
downstream from the inlet opening 22 for the purpose providing a
desired gas or fluid entry flow path within the heat exchanger.
[0024] FIGS. 3 to 5 each illustrate sectional views of the manifold
as used with heat exchangers of this invention. The manifold 42
includes a divider wall 44 therein that projects outwardly away
from an inside portion of the top surface 38. The divider wall 44
operates to form a distinct and separate inlet passage 46 and
outlet passage 48 within the manifold that each communicate with
respective manifold inlet and outlet openings 50 and 52. The
divider wall extends lengthwise internally within the manifold
separating the inlet and outlet ports, and forming a partition
along the core passages that are in communication with the manifold
inlet passage and outlet passage.
[0025] As illustrated in these figures, the manifold is configured
internally to accommodate attachment with an end of the shell and
adjacent a first end of the core. As shown each of FIGS. 3 to 5,
the end of the core is actually disposed a partial distance into
the manifold when the manifold is connected to the shell, as
illustrated in schematic by the line 54. It may also be located on
the end of the shell in the case of a flat plate configuration of
the core endplate.
[0026] As discussed above, an issue that exists with respect to
prior art heat exchangers is the unwanted bypassing of gas or fluid
within the manifold. This is caused by a gap or space that may
exist or develop between an end portion of the divider wall and an
adjacent surface of the core. While attempts have been tried to
address this issue through the use of an elastomeric seal, the use
of such elastomeric seal has not prevented such leakage. This is
due to the undesired distortion, softening, or disintegration of
the seal at the heat exchanger operating metal temperatures of
315.degree. C. or greater.
[0027] FIG. 3 illustrates a first embodiment of the invention as
used with heat exchangers to remedy this problem. In this first
embodiment, the manifold 42 includes a seal 56 that is interposed
between the divider wall 44 and an adjacent core surface 58, and
that may be attached to at least one of the divider wall or core.
In a preferred embodiment, the seal 56 is formed from a metallic
material and is configured having a first segment 60 that is
attached to an adjacent surface of the divider wall 62, and having
a second segment 64 that is integral with the first segment and
that projects inwardly towards the outlet passage 48.
[0028] The second segment 64 includes an end 66 that is configured
to abut against the adjacent core surface 58 when the manifold and
core are assembled together. The combined configuration of the
first and second segments provide a seal profile resembling a "V"
or having a "V-shaped" profile. The seal 56 is configured having a
length that spans the distance between the divider wall and core
within the manifold to provide a leak-tight seal against the core
for the length of the core.
[0029] The seal can be formed from any type of metallic material
that is capable of functioning to provide a desired seal when
placed into contact with or pressed against the core, and that is
capable of retaining a desired sealing engagement against the core
when exposed to heat exchanger operating metal temperatures, which
may exceed 315.degree. C. Additionally, the seal can be formed by
machining, stamping, rolling or other process, depending on the
particular material selected, configuration, and available
manufacturing equipment. In an example embodiment, the metallic
seal is formed from stainless steel and is made by a stamping
process.
[0030] In a preferred embodiment, the angle of projection as
measured between the seal first and second segments is in the range
of from about 110 to 170 degrees. Functionally, it is desired that
the angle provide a sufficient bias and loading force onto the core
when installed to provide a tight seal therebetween during the
high-temperature operating conditions within the heat exchanger.
Additionally, it is desired that first and second segments each be
of sufficient dimension to help provide the above-noted desired
loading force onto the core.
[0031] The seal can be attached to the divider wall by conventional
methods, such as by welded, bolted, riveted attachment or the like.
In an example embodiment, the seal 56 is attached by welding.
Additionally, while the seal is shown in FIG. 3 as being attached
to the inlet passage side of the divider wall 44, the seal can
alternatively be attached to the outlet passage side of the divider
wall if so desired.
[0032] FIG. 4 illustrates a second embodiment of the invention as
used with heat exchangers. In this second embodiment, like the
first embodiment, the manifold 42 includes a seal 68 that is
interposed between the divider wall 44 and the core. In this
particular embodiment, the seal 68 is formed from the same types of
metallic materials disclosed above for the first embodiment, and is
generally configured having an "M-shaped" profile.
[0033] Specifically, the seal 68 is configured having a central
groove 70 that is sized and shaped to accept placement of the
divider wall end 72 therein, and having a pair of raised ridges 74
surrounding the groove 70 that operate to help center placement of
the divider wall end within the seal. Moving away from each raised
ridge, the seal 68 includes a pair of base members or feet 76 that
are configured for placement against the core. Configured in this
manner, the seal groove 70 forms a seal with the divider wall and
the seal feet 76 form a seal with the core.
[0034] Additionally, the seal 68 is provided in the form of a
one-piece construction comprising the groove, raised ridges and
feet that together operate to provide a self-loading mechanism
between the divider wall and core, when the core and manifold are
assembled together. This operates to provide and maintain a desired
loading force for forming a seal between the divider wall and the
core during heat exchanger operation. In a preferred embodiment,
the seal 68 is formed from stainless steel and is made by a
stamping process.
[0035] Although the seal 68 as illustrated in FIG. 4 is shown
without being attached to the divider wall other than by loading
force, if desired, the seal 68 can be attached to the divider wall.
For example, the seal can be attached by welded attachment or the
like at the interface between the divider wall and the groove.
[0036] FIG. 5 illustrates a third embodiment of the invention as
used with heat exchangers. In this third embodiment, like the first
embodiment, the manifold 42 includes a seal 78 that is interposed
between the divider wall 44 and the core 54. In this particular
embodiment, the seal 78 is formed from the same types of metallic
materials disclosed above for the first embodiment, and is
generally configured having a "C-shaped" profile.
[0037] Specifically, the seal 78 is configured having a central
groove 80 that is sized and shaped to accommodate placement of the
divider wall end 82 therein. The seal 78 includes a pair of legs or
ends 84 that are integral with the groove and that each extend
along respective opposed wall surfaces of the divider wall. The
legs are attached to the divider wall by the same attachment
methods noted above for the first invention embodiment. The seal 78
includes a base 86, defining an outside surface of the groove from
which the legs extend, and that is positioned against an adjacent
core surface 88. Configured in this manner, the seal legs 84 form a
desired seal with the divider wall, and the seal base 80 forms a
desired seal with the core.
[0038] Additionally, the seal 78 is provided in the form of a
one-piece construction comprising the groove, legs, and base. The
legs project outwardly from the base at less than a 90-degree
angle, thereby providing a loading mechanism when the legs are each
secured to the divider wall and the core and manifold are assembled
together. This loading mechanism imposes a desired biasing force
against the core surface to provide the desired seal between the
core and seal during heat exchanger operation. In a preferred
embodiment, the seal 78 is formed from stainless steel and is made
by a stamping process.
[0039] FIG. 6 illustrates an alternative embodiment of the
invention whereby the sealing mechanism between the divider wall 44
and the core 54 is provided without the use of an external element.
Rather, in this specific embodiment, the sealing mechanism is
provided by the manifold divider wall having an end 90 that is
specially configured to complement and fit together with a
complementary surface portion 92 of the core. In an example
embedment, the manifold divider wall is configured with an end 90
that is sized and shaped to fit within a groove 92 disposed within
the adjacent core surface to provide a tongue and groove attachment
mechanism therebetween.
[0040] While specific invention embodiments useful with heat
exchangers have been described and illustrated, it is to be
understood that these embodiments are only exemplary of the many
different types of inventive seals that can be installed and used
with heat exchangers for the purpose of minimizing or eliminating
bypass flow within the heat exchanger hot-side manifold within the
scope of this invention.
[0041] Additionally, although the different embodiments of this
invention have been described and illustrated as being positioned
within a hot-side manifold having a particular inlet or outlet
configuration, it is to be understood that heat exchanger seals of
this invention can be used in other types of heat exchanger
manifolds configured other than that specifically described and/or
illustrated that generally use the interaction of a divider wall
with the core to separate hot-side inlet and outlet gas or fluid
flow therein.
[0042] Further, although the specific embodiments of this invention
had been described in the context of a shell and tube-type heat
exchanger, it is to be understood that the seal embodiments of this
invention can be used with other types of heat exchangers, such as
bar and plate heat exchangers, that use divider walls within a heat
exchanger hot-side manifold to provide a seal between and separate
inlet and outlet flow streams.
[0043] Heat exchangers comprising seals constructed in accordance
with this invention operate to minimize or eliminate the unwanted
bypass of gas or fluid within the heat exchanger manifold to enable
the realization of improved heat exchanger operational
efficiency.
* * * * *