U.S. patent application number 15/177559 was filed with the patent office on 2016-12-15 for modular heat exchanger design.
The applicant listed for this patent is Hamilton Sundstrand Corporation. Invention is credited to Eric A. Carter, John Horowy, John Huss, Eric Karlen, Mark W. Metzler, Debabrata Pal, Mark Hamilton Severson.
Application Number | 20160363390 15/177559 |
Document ID | / |
Family ID | 56409676 |
Filed Date | 2016-12-15 |
United States Patent
Application |
20160363390 |
Kind Code |
A1 |
Karlen; Eric ; et
al. |
December 15, 2016 |
MODULAR HEAT EXCHANGER DESIGN
Abstract
A cold plate assembly is provided having a base defining a
cooling channel and a heat exchanger friction-stir welded to the
base, wherein the heat exchanger is located within a portion of the
cooling channel, and the friction-stir welding between the heat
exchanger and the base forms a fluid seal.
Inventors: |
Karlen; Eric; (Rockford,
IL) ; Horowy; John; (Rockford, IL) ; Severson;
Mark Hamilton; (Rockford, IL) ; Metzler; Mark W.;
(Davis, IL) ; Carter; Eric A.; (Monroe, WI)
; Huss; John; (Roscoe, IL) ; Pal; Debabrata;
(Hoffman Estates, IL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Hamilton Sundstrand Corporation |
Charlotte |
NC |
US |
|
|
Family ID: |
56409676 |
Appl. No.: |
15/177559 |
Filed: |
June 9, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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62173119 |
Jun 9, 2015 |
|
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15177559 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F28F 2275/062 20130101;
F28F 3/10 20130101; F28F 3/12 20130101; F28D 15/00 20130101; F28F
3/04 20130101; F28F 3/027 20130101; B23K 20/122 20130101; F28D
2021/0028 20130101; H01L 21/4882 20130101; H01L 23/473 20130101;
F28F 3/025 20130101 |
International
Class: |
F28F 3/10 20060101
F28F003/10; F28F 3/04 20060101 F28F003/04; F28F 3/12 20060101
F28F003/12; F28D 15/00 20060101 F28D015/00; F28F 3/02 20060101
F28F003/02 |
Claims
1. A cold plate assembly comprising: a baseplate defining a cooling
channel; and a heat exchanger friction-stir welded to the
baseplate, wherein the heat exchanger is located within a portion
of the cooling channel, and the friction-stir welding between the
heat exchanger and the baseplate forms a fluid seal.
2. The cold plate assembly of claim 1, further comprising a cover,
the cover configured to attach to the baseplate.
3. The cold plate assembly of claim 2, wherein the cover forms a
lid over the cooling channel where the heat exchanger is not
located.
4. The cold plate assembly of claim 2, wherein the cover is
friction-stir welded to a portion of the heat exchanger.
5. The cold plate assembly of claim 2, wherein the cover is
friction-stir welded to the baseplate.
6. The cold plate assembly of claim 1, wherein the heat exchanger
is integral with a component to be cooled by the heat
exchanger.
7. The cold plate assembly of claim 1, wherein the heat exchanger
comprises a plurality of fins defining a plurality of fluid
channels between the plurality of fins.
8. The cold plate assembly of claim 1, wherein the cooling channel
of the baseplate includes a plurality of cooling fins and the heat
exchanger includes a plurality of cooling fins configured to
interleave with the cooling fins of the baseplate.
9. The cold plate assembly of claim 1, wherein the baseplate
includes a second cooling channel, the assembly further comprising
a top cold plate friction stir welded on the baseplate over the
second cooling channel.
10. A method of manufacturing a cold plate assembly, the method
comprising: friction stir welding a heat exchanger to a baseplate,
the baseplate defining a cooling channel, the heat exchanger
located within a portion of the cooling channel, and the
friction-stir welding between the heat exchanger and the baseplate
forms a fluid seal.
11. The method of claim 10, further comprising attaching a cover to
the baseplate.
12. The method of claim 11, wherein the cover forms a lid over the
cooling channel where the heat exchanger is not located.
13. The method of claim 11, further comprising friction-stir
welding the cover to a portion of the heat exchanger.
14. The method of claim 11, further comprising friction-stir
welding the cover to the baseplate.
15. The method of claim 10, wherein the heat exchanger is integral
with a component to be cooled by the heat exchanger.
16. The method of claim 10, wherein the heat exchanger comprises a
plurality of fins defining a plurality of fluid channels between
the plurality of fins.
17. The method of claim 10, wherein the cooling channel of the
baseplate includes a plurality of cooling fins and the heat
exchanger includes a plurality of cooling fins, the method
comprising interleaving the cooling fins of the baseplate with the
cooling fins of the heat exchanger.
18. The method of claim 10, wherein the baseplate includes a second
cooling channel, the method comprising friction stir welding a top
cold plate on the baseplate over the second cooling channel.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Application Ser. No. 62/173,119 entitled "Modular Heat Exchanger
Design", filed Jun. 9, 2016, under 35 U.S.C. .sctn.119(e), and
which is incorporated herein by reference in its entirety.
BACKGROUND
[0002] The subject matter disclosed herein generally relates to
heat exchangers and, more particularly, to heat exchangers and
processes for forming the same.
[0003] Cold plate heat exchangers may be used to cool electronic
components that are mounted thereto. In some electronics, the heat
exchangers and thermal flow paths may be built into a structure
that allows mounting of the electronics to be cooled. Current
manufacturing processes for the cold plate style heat exchanger
structures may involve multiple processes. The operations and
processes of current manufacturing techniques may include
machining, brazing, etc. along with multiple additional components,
including fasteners, washers, etc.
SUMMARY
[0004] According to one embodiment a cold plate assembly is
provided having a base defining a cooling channel and a heat
exchanger friction-stir welded to the base, wherein the heat
exchanger is located within a portion of the cooling channel, and
the friction-stir welding between the heat exchanger and the base
forms a fluid seal.
[0005] According to another embodiment, a cold plate assembly is
provided as shown and described herein.
[0006] According to another embodiment, a method of manufacturing a
cold plate assembly is provided as shown and described herein.
[0007] According to another embodiment, a cold plate assembly as
formed as shown and described herein is provided.
[0008] Technical effects of embodiments of the present disclosure
include a modular formed cold plate heat exchanger. Other technical
effects include the elimination of brazing during heat exchanger
manufacture along with the elimination of added parts that may have
previously been required.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The subject matter is particularly pointed out and
distinctly claimed at the conclusion of the specification. The
foregoing and other features, and advantages of the present
disclosure are apparent from the following detailed description
taken in conjunction with the accompanying drawings in which:
[0010] FIG. 1A is an isometric view of a fin core used in cold
plate assemblies;
[0011] FIG. 1B is a side view schematic of a prior configuration of
a cold plate assembly;
[0012] FIG. 1C is a thermal flow progression of thermal energy
through a cold plate assembly, indicating where a component may be
installed;
[0013] FIG. 2 is an isometric view of a cold plate assembly as
formed by prior techniques;
[0014] FIG. 3 is an isometric view of a cold plate assembly as
formed by a technique described herein;
[0015] FIG. 4 is a schematic illustration of a friction-stir
welding process as used by embodiments described herein;
[0016] FIG. 5 is a schematic illustration of a heat exchanger and
installation in a cold plate assembly in accordance with an example
embodiment;
[0017] FIG. 6 is an illustration of a heat exchanger attached to a
structure in accordance with an example embodiment;
[0018] FIG. 7 is a schematic illustration of a cold plate assembly
in accordance with an embodiment of the present disclosure; and
[0019] FIG. 8 is a schematic illustration of a cold plate assembly
in accordance with another embodiment of the present
disclosure.
DETAILED DESCRIPTION
[0020] As shown and described herein, various features of the
disclosure will be presented. Various embodiments may have the same
or similar features and thus the same or similar features may be
labeled with the same reference numeral, but preceded by a
different first number indicating the figure to which the feature
is shown. Thus, for example, element "a" that is shown in FIG. 1
may be labeled "1a" and a similar feature in FIG. 2 may be labeled
"2a." Although similar reference numbers may be used in a generic
sense, various embodiments will be described and various features
may include changes, alterations, modifications, etc. as will be
appreciated by those of skill in the art, whether explicitly
described or otherwise would be appreciated by those of skill in
the art.
[0021] FIG. 1A is an isometric view of fin core 102 of a heat
exchanger 100. The fin core 102 includes a plurality of fins 104
that form channels therebetween. Fluid may be passed through the
channels between the fins 104 to enable thermal cooling to a
component or device. For example, as shown in FIG. 1B, the heat
exchanger 100 is housed within a cold plate 104. Mounted on the
cold plate 104 may be one or more components 106. The component 106
may be an electrical component that includes inductors, diodes,
capacitors, etc., and in some embodiments the component 106 may be
a power distribution system. As will be appreciated by those of
skill in the art, the combination of the heat exchanger 100 and the
cold plate 104 form a cold plate heat exchanger that may be used to
cool electronics or other thermal energy generating devices.
[0022] Formed between the component 106 and the cold plate 104 may
be a thermal interface 108. The thermal interface 108 is a joined
surface between the component 106 and the cold plate 104 and
enables the heat exchanger 100 to provide thermal cooling to the
component 106. For example, working or operating fluid may pass
through the heat exchanger 100 (and through the fin core 102
thereof) and heat or thermal energy may be passed from the
component 106, through the thermal interface 108, and into the
operating fluid that is passing through the channels formed by the
fins 104 of the fin core 102. The heat exchanger 100 and cold plate
104 may be part of a cold plate assembly.
[0023] FIG. 1C shows a thermal gradient or flow path of a cooling
fluid or operating fluid that may be used to work with the fin core
100 to cool a component, such as component 106, as the fluid flows
through a cold plate assembly 110. For example, as shown, the
component 106 may be mounted on the cold plate assembly 110 along a
flow path 112. An operating fluid may enter the flow path 112 at an
inlet 114, flow counter-clockwise in FIG. 1C, and exit the flow
path 112 at outlet 116. As shown, the component 106 is located
along the flow path 112 and thus may be cooled by the operating
fluid passing below the component 106. The heat exchanger 100
(shown in FIGS. 1A and 1B) may be located within the cold plate
assembly 110 and located directly below the component 106. Thus,
the heat exchanger 100 may be part of the flow path 112, and an
operating fluid may pass through the heat exchanger 100 to enable
cooling of the component 106. The flow path 112 may be one or more
cooling channels that are formed in or on the cold plate assembly
110.
[0024] Traditionally, the heat exchanger 100 is placed into and
brazed as part of the flow path 112 and within a cooling channel in
a cold plate assembly. The heat exchanger 100 may be vacuum brazed
with an integrated lanced offset fin section that is then placed
into the cooling channels of the cold plate assembly 110. After
placement, the heat exchanger 100 may be brazed in place. The heat
exchanger 100, in some configurations, may further be bolted into
place and be surrounded by an O-ring or other type of seal that is
configured to provide a fluid seal to keep the operating fluid
within the fin core 100. That is, additional hardware may be
required to provide a proper connection and fluid seal between the
heat exchanger and the cold plate assembly.
[0025] Turning to FIG. 2, an isometric view of a cold plate
assembly housing a heat exchanger is shown. Cold plate assembly 210
is formed from a base 218 and a cover or lid 220. The base 218 and
the cover 220 may be machined into a proper configuration with a
flow path or fluid channel formed between the base 218 and the
cover 220. Also housed between the base 218 and the cover 220 at
portion 222 may be a heat exchanger such as described above. The
heat exchanger, housed at portion 222, may be provided with an
operating fluid that passes through the cold plate assembly 210
along a flow path beneath the cover 220. The flow path may provide
the operating fluid at an inlet side of the portion 222 at an inlet
224 and may exit the portion 222 at an outlet 226. FIG. 2 shows a
prior configuration wherein machining is used to form both the base
218 and the cover 220 together, with the flow path or fluid channel
formed in a surface of the base 218 between the base 218 and the
cover 220. As such, the cover 220 is formed with substantially the
same shape as the base 218, as shown in FIG. 2.
[0026] Complex cold plate assemblies for large power motor
controllers have high density fin cores for enhanced thermal
management. These cold plates are typically vacuum brazed. This
manufacturing process is expensive. In addition, the high heat flux
components such as insulated-gate bipolar transistor (IGBT) modules
are mounted with thermal grease or other interface material between
base plate and cold plate. In other configurations, a power module
with fins is used with O-rings to eliminate thermal interface
between the cold plate and an IGBT module. Embodiments provided
herein are directed to an improved cold plate assembly and methods
of manufacture. For example, a manufacturing method is provided
herein where an IGBT module is integrally joined to a cold plate
(e.g., by friction stir welding), thus eliminating the thermal
interface. In addition, an interleaved machined fin structure is
provided herein to replace lanced offset fin cores which provides
adequate heat transfer co-efficient x-area to both sides of a cold
plate.
[0027] Turning now to FIG. 3, a structure of a cold plate assembly
310 is shown in accordance with an embodiment of the present
disclosure. As shown, a base 318 of the cold plate assembly 310 has
a similar structure and configuration as the base 218 of FIG. 2.
However, in accordance with embodiments disclosed herein, the cover
320 may not be machined at the same time as the base 218 or formed
in the same shape or geometry thereof. In contrast, the cover 320
of embodiments disclosed herein may be modular and pre-fabricated,
and in some embodiments may be formed from one or more parts or
sections. In some embodiments, the cover 320 may sit or rest on a
shoulder of the base 318 such that when the cover 320 is attached
to the base 318, a fluid channel is formed and sealed between the
base 318 and the cover 320.
[0028] As shown in FIG. 3, the portion 322 of the cover 320 is
separate or distinct from the rest of the cover 320. That is, the
portion 322, where a heat exchanger may be installed, may be
separate from the cover 320 that is used to form parts of the fluid
channel in the cold plate assembly 310. That is, in the embodiment
shown in FIG. 3, the portion 322 may be a base or surface of a heat
exchanger, and in some embodiments may be a base that supports a
fin core that is attached directly to a surface of the base
318.
[0029] In some embodiments, a component may then be attached or
connected to the heat exchanger at portion 322. In other
embodiments, the portion 322 may represent the component itself.
That is, in some embodiments, the fins of the heat exchanger may be
formed integral with or attached directly to a component which may
then be directly attached to the case 318.
[0030] In accordance with embodiments disclosed herein, the
portions of the cover (cover 320, portion 322 (whether as a
separate heat exchanger or as a component), etc.) may be
friction-stir welded directly to the base 318. That is, cold plate
machining may be used to create cooling channels within the base
318 into which pre-fabricated heat exchanger elements or sections
(e.g., portion 322) may be placed. Once placed, the heat exchanger
element may be friction-stir welded into or onto the base 318 of
the cold plate assembly 310. The other portions of the cover 320,
such as a lid or multiple lids, may be placed over channels formed
in the base 318 of the cold plate assembly 310 and may also be
friction-stir welded into place to create the internal cooling
channels of the cold plate assembly 310.
[0031] Turning to FIG. 4, an example of friction-stir welding is
shown. A tool 430 is provided that rotates as shown by tool
rotation arrows 432. A contact force 434 is applied downward on the
tool 430 such that a portion of the tool 430, such as a shoulder
440 and a probe 438, may contact a joint line 436. The joint line
436 may be a joint line between a surface of a cover or lid 420 and
a surface of a base 418. As the tool 430 rotates, a probe 438 is
used to contact the surface at the joint line 436 and a shoulder
440 of the tool 430 enables a smooth finish to be formed at a
trailing edge 442. Thus, by means of the rotation 432 and the
contact force 434, along with a traversing force 444, the two
components of the joint line 436 may be friction-stir welded. As
will be appreciated by those of skill in the art, friction-stir
welding is a solid-state joining process wherein materials of two
elements to be joined are not melted. Friction-stir welding uses a
third body tool (e.g., tool 430) to join two facing surfaces (e.g.,
a cover 420 and a base 418 of a cold plate assembly). Heat is
generated between the tool 430 and the materials of the base 418
and the cover 420, which leads to a very soft region near the tool
430. The tool 430 then mechanically intermixes the materials of the
cover 420 and the base 418 at the place of the joint line 436. The
softened material can then be joined, welded, or fused using
mechanical pressure (which is applied by the tool 430, e.g.,
contact force 434).
[0032] Turning to FIG. 5, a schematic of a heat exchanger 550 and
in indication of the heat exchanger 550 as friction-stir welded
into a fluid channel of a cold plate assembly is shown. On the left
side of FIG. 5 is a schematic of a modular heat exchanger 550. The
modular heat exchanger 550 is formed from a base 552, a fin core
554, and a top 556. The modular heat exchanger 550 may be a
pre-fabricated module that may be dropped into or installed within
a manufactured or machined part. For example, with reference back
to FIG. 3, the modular heat exchanger 550 may form or be installed
into portion 322. The heat exchanger 550 may have a similar fin
core to that shown and described above.
[0033] As will be appreciated by those of skill in the art,
although the modular heat exchanger 550 is shown with a rectangular
or square geometry with a top and a bottom, other configurations of
modular heat exchangers may be used without departing from the
scope of the present disclosure. That is, any geometry, shape,
size, etc. may be used for the heat exchanger, and further, the top
and/or bottom may be omitted based on the configuration and needs
of a particular design. Thus, FIG. 5, and the other figures, are
merely provided as examples and are not to be taken as
limiting.
[0034] Shown on the right-hand side of FIG. 5, a schematic of the
heat exchanger 550 as installed is shown. As shown, the heat
exchanger 550 may be friction-stir welded into place as indicated
by the edge or welding 558. Also shown on the right-hand side of
FIG. 5 are two sections of a cover 520. The cover 520 may be
substantially similar to the covers and lids described above and
may also be friction-stir welded to a base. As shown, the
friction-stir welding 558 may be continuous about the sections of
the cover 520 and about the heat exchanger 550. Thus, a fluid seal
may be provided to prevent leaking of the operating fluid. Due to
the friction stir welding used to join the heat exchanger 550 and
the sections of the cover 520 to a base, the heat exchanger 550 and
the covers 520 may form a continuous surface. That is, the top 556
of the heat exchanger 550 may be mixed with the covers 520 during
the friction-stir welding process, as described above.
[0035] FIG. 6 shows an image of a heat exchanger 650 as attached to
a structure 660 in accordance with embodiments described
herein.
[0036] FIG. 7 is a schematic illustration of a power module 701 as
installed on a power module baseplate 703. The power module 701,
through the power module baseplate 703, is mounted to a cold plate
705. In the non-limiting embodiment of FIG. 7, the power module
baseplate 703 includes integral fins 707, which can, for example,
be formed by machining or brazed fins. Similarly, as shown, there
are cold plate fins 709 on the cold plate 705. The power module
baseplate 703 is brazed by friction stir welding in a window cut
out of the cold plate 705. The power module baseplate fins 707 are
placed in the space between the cold plate fins 709 forming an
interleaved fin structure, as shown. Such configuration allows for
high heat dissipating components located on both sides of the cold
plate 705 (e.g., above or below the cold plate 705 in FIG. 7).
[0037] Turning now to FIG. 8, a schematic illustration of a cold
plate 821 having interleaved fins 823 and a cooling channel 825 is
shown. A component configuration with such fin structure (e.g.,
fins 823) and cooling channel (e.g., cooling channel 825) is
created by placing the power module baseplate 827 over the fins 823
of the cold plate 821 and friction stir welding the two components
together. Further, as shown in FIG. 8, a top cold plate 829 and
joining the top and bottom portions of the cold plate (e.g., cold
plate 821 and top cold plate 829) by friction stir welding.
[0038] In some embodiments of the present disclosure, modified fin
densities can be employed. For example, similar to the embodiments
of FIGS. 7-8, high density fin arrangements can be manufactured
such that individual plates have relatively low fin density but
have the plates opposing each other with interleaved fins to obtain
higher effective fin density.
[0039] Advantageously, embodiments described herein provide a cold
plate assembly that is friction-stir welded. By having
friction-stir welded components, embodiments disclosed herein may
enabled modular components, including modular heat exchanger
components, without added expense, costs, manufacturing times, or
other impacts. For example, that may be significant lead-time
reductions as compared to traditional cold plate assembly
manufacturing processes. Further, there may be significant cost
savings, by reducing the number of parts, components, operations,
processes, etc. Moreover, the friction-stir welding process may
enable joining of covers/heat exchangers with a base without the
need for fillers, fasteners, etc.
[0040] Further, advantageously, in accordance with some
embodiments, the heat exchanger may be formed integral or attached
with the component to which it is designed to cool, and thus enable
optimized thermal transfer. Further, the entire component
(component with attached or integral heat exchanger) may be
friction-stir welded into the cold plate to thus form an
inseparable assembly.
[0041] Further, advantageously, a friction-stir welded cold plate
assembly as described herein may enable a strong metallurgic bond
to be formed between the friction-stir welded components, thus
provided a fluid seal. Accordingly, advantageously, O-rings and
other seals and/or bonding or fastening elements may be eliminated
during the manufacturing process.
[0042] Moreover, advantageously, various embodiments provided
herein can allow the elimination of thermal interface between power
modules and cold plates. Removal of the thermal interface may
enable temperature reductions of the power module. Accordingly,
power modules as prepared in accordance with the present disclosure
may have increased reliability. In addition, advantageously,
embodiments provided herein can eliminate vacuum brazing and
potentially reduce cold plate cost.
[0043] While the present disclosure has been described in detail in
connection with only a limited number of embodiments, it should be
readily understood that the present disclosure is not limited to
such disclosed embodiments. Rather, the present disclosure can be
modified to incorporate any number of variations, alterations,
substitutions, combinations, sub-combinations, or equivalent
arrangements not heretofore described, but which are commensurate
with the spirit and scope of the present disclosure. Additionally,
while various embodiments of the present disclosure have been
described, it is to be understood that aspects of the present
disclosure may include only some of the described embodiments.
[0044] For example, although shown and described with respect to a
particular shape and design for a heat exchanger, those of skill in
the art will appreciate that any shape, design, configuration, or
geometry may be used for the modular heat exchanger. Further, as
described, the heat exchanger may be formed as attached to or
integral with the component that is configured to be cooled. The
unitary component-heat exchanger may then be installed into an
appropriate portion of a fluid channel and then friction-stir
welded into place to form a sealed, secure assembly.
[0045] Accordingly, the present disclosure is not to be seen as
limited by the foregoing description, but is only limited by the
scope of the appended claims.
* * * * *