U.S. patent application number 13/490538 was filed with the patent office on 2013-12-12 for cold plate assembly incorporating thermal heat spreader.
The applicant listed for this patent is Jeremy M. Strange, Mark A. Zaffetti. Invention is credited to Jeremy M. Strange, Mark A. Zaffetti.
Application Number | 20130327508 13/490538 |
Document ID | / |
Family ID | 48576751 |
Filed Date | 2013-12-12 |
United States Patent
Application |
20130327508 |
Kind Code |
A1 |
Zaffetti; Mark A. ; et
al. |
December 12, 2013 |
COLD PLATE ASSEMBLY INCORPORATING THERMAL HEAT SPREADER
Abstract
An example cold plate assembly includes a heat spreader assembly
that defines a mounting surface for heat generating devices and
provides an improved thermal conduction of heat away from the heat
generating devices. The example heat spreader assembly provides a
more uniform thermal gradient across the mounting surface of the
cold plate assembly and improves thermal conductivity and cooling
provided by the cold plate assembly.
Inventors: |
Zaffetti; Mark A.;
(Suffield, CT) ; Strange; Jeremy M.; (Windsor,
CT) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Zaffetti; Mark A.
Strange; Jeremy M. |
Suffield
Windsor |
CT
CT |
US
US |
|
|
Family ID: |
48576751 |
Appl. No.: |
13/490538 |
Filed: |
June 7, 2012 |
Current U.S.
Class: |
165/168 ;
29/890.03 |
Current CPC
Class: |
H01L 23/373 20130101;
H01L 2924/00 20130101; H01L 23/3735 20130101; H01L 2924/0002
20130101; Y10T 29/4935 20150115; H01L 2924/0002 20130101; H01L
23/473 20130101 |
Class at
Publication: |
165/168 ;
29/890.03 |
International
Class: |
F28F 3/12 20060101
F28F003/12; B21D 53/02 20060101 B21D053/02 |
Goverment Interests
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0001] This subject of this disclosure was made with government
support under Contract No.: NNJO6TA25C awarded by the National
Aeronautics and Space Administration. The government therefore may
have certain rights in the disclosed subject matter.
Claims
1. A cold plate assembly comprising: a heat spreader defining a
surface for mounting heat generating devices; a plurality of heat
dissipating members comprising ruffled fins in thermal
communication with the heat spreader; and an end sheet defining a
surface opposite the heat spreader.
2. The cold plate assembly as recited in claim 1, wherein the heat
spreader comprises a graphite material.
3. The cold plate assembly as recited in claim 2, wherein the heat
spreader comprises an annealed pyrolytic graphite.
4. The cold plate assembly as recited in claim 1, wherein the heat
spreader comprises an upper skin, a bottom skin and a layer of
annealed pyrolytic graphite between the upper and lower skin.
5. The cold plate assembly as recited in claim 1, wherein the heat
dissipating members comprise first and second layers of ruffled
fins separated by a parting sheet.
6. The cold plate assembly as recited in claim 5, including a first
closure bar disposed about the first layer of ruffled fins and a
second closure bar disposed about the second layer of ruffled
fins.
7. The cold plate assembly as recited in claim 6, including
additional parting sheets disposed on corresponding sides of the
first and second layers of ruffled fins opposite the first parting
sheet.
8. The cold plate assembly as recited in claim 7, including an
inlet and outlet for communicating a cooling medium through the
first and second layers of ruffled fins.
9. The cold plate assembly as recited in claim 7, including a
brazed joint attaching the heat spreader to a parting sheet.
10. A method of assembling a cold plate comprising: defining a
mounting surface with a heat spreader; attaching the heat spreader
to a fin assembly including a plurality of ruffled fins; and
attaching an end sheet to a side of the fin assembly opposite the
heat spreader.
11. The method as recited in claim 10, wherein the fin assembly
includes a first parting sheet defining a first surface of the fin
assembly, a closure bar surrounding the plurality of ruffled fins
and a second sheet defining a second surface opposite the first
surface to which the heat spreader is attached.
12. The method as recited in claim 10, including assembling the
heat spreader by attaching a top skin and a bottom skin to a middle
layer of heat spreading material.
13. The method as recited in claim 12, wherein the heat spreading
material comprises annealed pyrolytic graphite.
14. The method as recited in claim 11, including attaching an inlet
fitting to the first parting sheet to define a fluid inlet and
attaching an outlet fitting to the first parting sheet to define a
fluid outlet.
15. The method as recited in claim 11, including attaching the heat
spreader to the fin assembly with a brazed joint.
16. The method as recited in claim 10, including defining a fluid
passage through the heat dissipating layer through the ruffled
fins.
Description
BACKGROUND
[0002] This disclosure generally relates to a cooling structure for
cooling electronic components. More particularly, this disclosure
relates to a cooling structure including a cold plate support
assembly.
[0003] Electronic components onboard aircraft or other vehicles
that operate in extreme temperatures are typically protected from
overheating by a cooling device. In some environments, air flow is
either not available or insufficient to handle the thermal loads
generated by the electronic components. In such applications, a
cold plate is utilized through which a cooling fluid flows to
remove heat from the electronic component. The cold plate is
mounted adjacent the electronic component and supplied with fluid
flow through appropriate conduits that lead to a fluid delivery
system.
SUMMARY
[0004] An example cold plate assembly according to an exemplary
embodiment of this disclosure, among other possible things includes
a heat spreader assembly that defines a mounting surface for heat
generating devices and provides an improved thermal conduction of
heat away from the heat generating devices. The example cold plate
assembly with the integral heat spreading device spreads heat
throughout the area of the mounting surface to reduce non-uniform
thermal gradients across the cold plate assembly. Accordingly, the
example heat spreader assembly provides a more uniform thermal
gradient across the mounting surface of the cold plate assembly and
improves thermal conductivity and cooling provided by the cold
plate assembly.
[0005] Although the different examples have the specific components
shown in the illustrations, embodiments of this invention are not
limited to those particular combinations. It is possible to use
some of the components or features from one of the examples in
combination with features or components from another one of the
examples.
[0006] These and other features disclosed herein can be best
understood from the following specification and drawings, the
following of which is a brief description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a perspective view of an example cold plate
assembly.
[0008] FIG. 2 is a cross section of the example cold plate
assembly.
[0009] FIG. 3 is an exploded view of the example cold plate
assembly.
[0010] FIG. 4 is a perspective view of an example ruffled fin
assembly.
[0011] FIG. 5 is a perspective view of an example heat spreader
assembly.
DETAILED DESCRIPTION
[0012] Referring to FIG. 1, an example cold plate assembly 10
includes an upper mounting surface 14 and a bottom surface 16. The
upper mounting surface 14 defines an area for mounting heat
generating devices 12. The example heat generating devices 12 are
electronic components that generate heat dissipated through the
cold plate assembly 10. The example cold plate assembly 10 includes
fluid inlet fitting 42 that receive a cooling medium input
indicated at 56 that removes heat from the cold plate assembly 10
generated by the heat generating device 12 and carries the heated
cooling medium away through outlet fitting 44 as indicated at 58.
Further, although the example structural cooling plate assembly 10
includes two separate cooling circuits any number of cooling
circuits are also within the contemplation of this disclosure.
[0013] As appreciated, the heat generating devices 12 are mounted
to a specific location on the mounting surface 14. Accordingly,
generated heat is not evenly produced across the mounting surface
14.
[0014] The example mounting surface 14 is part of an upper skin 22
of a heat spreading assembly 20. A heat spreading assembly 20
provides for not only the dissipation of heat within a localized
area but a spreading of the heat across a much wider area or
surface to evenly distribute thermal energy produced by locally
mounted heat generating devices 12. The example heat spreader
assembly 20 is an integral part of the cold plate assembly 10 and
defines the mounting surface 14 on which the various heat
generating devices 12 are mounted.
[0015] As appreciated, the example mounting surface 14 is indicated
as a planar surface for mounting of the various heat generating
devices 12. However, the mounting surface 14 could be of any shape
desired to accommodate application specific mounting requirements
for the various heat generating devices. Moreover, although the
example heat generating devices 12 are described as electronic
components they may also comprise any other devices that generate
heat that are desired to be cooled through a passive means as is
provided by the example cold plate assembly 10.
[0016] Referring to FIGS. 2 and 3 with continued reference to FIG.
1, the example cold plate assembly 10 is made up of a plurality of
layers. Heat generated by the heat generating devices 12 is
initially absorbed through the mounting surface 14 into the cold
plate assembly 10. Heat produced by the heat producing devices 12
is spread out across the area defined by the heat spreader assembly
20 comprising the mounting surface 14. The heat is then absorbed
within the cold plate assembly 10 through the various layers
illustrated in FIG. 2.
[0017] The example cold plate assembly 10 includes the heat
spreader 20 that is attached to a top parting sheet 38. The parting
sheet 38 provides a top layer to seal a conduit through which a
fluid medium is provided through inlets 42. A middle parting sheet
36 is disposed in a middle portion of the cold plate assembly and
supports a closure bar 32. The closure bar 32 surrounds a finned
layer 28. Fluid flows through the fins 28 to remove thermal energy
produced by the heat generating devices 12. Although a single heat
spreader 20 is shown, it is within the contemplation of this
disclosure that additional heat spreaders could be included within
the example cold plate assembly 10. For example, an additional heat
spreader could be installed between the finned layers 28, 30 to
further enhance heat removal.
[0018] The example cold plate assembly includes a first layer 28 of
fins and a second layer 30 of fins. Each of the layers of fins 28,
30 are bounded by closure bars 32, 34. The closure bars 32, 34
define a boundary for the various fluid passages that are defined
between the plurality of fins 50 (FIG. 4) within each of the layers
28, 30. A bottom parting sheet 40 is disposed on a bottom surface
of the second layer 30 of fins that is opposite the middle parting
sheet 36. The end sheet 18 is disposed in contact with the bottom
parting sheet 40.
[0019] In this example, each of the parting sheets 36, 38, and 40
comprise an aluminum sheet material that is brazed in place to form
the desired fluid conduits through which a cooling medium is
provided. Each of the parting sheets 36, 38, and 40 of the example
cold plate assembly 10 are brazed to each other at brazed joints
indicated at 48. The heat spreader assembly 20 is further attached
by a brazed joint 46 with the top parting sheet 38.
[0020] The example heat spreader assembly 20 includes the upper
skin 22, a middle skin 24, and a lower skin 26. The middle skin 24
comprises a material that is selected from a group of materials
that provides for the dissipation in a direction transverse to a
thickness of the sheet. In other words, the heat spreader assembly
20 is comprised of layers of material that not only provide a low
thermal resistance in a direction through the thickness of the
material but also spreads the heat in a direction perpendicular to
the thickness of the material about the area of the mounting
surface 14. The outer skins 22, 26 are of a material brazeable and
that mechanically encapsulate the center skin 24.
[0021] In this example, the heat spreader 20 comprises a material
including graphite. The graphite provides for the spreading of
thermal energy produced by the various heat generating components
12 across the area of the mounting surface 14 as indicated by
arrows shown in FIG. 1. In this example, the heat spreader center
skin 24 is fabricated from annealed pyrolytic graphite (APG). As
should be appreciated, although an APG material is used in the
disclosed example cold plate assembly 10 and heat spreader assembly
20 other materials and configurations that provide for the
spreading of heat are also within the contemplation of this
disclosure. The outer skins 22, 26 are comprised of material that
is brazeable to the other cold plate components.
[0022] Referring to FIG. 4 with continued reference to FIG. 2, the
example fin layers 28 and 30 comprise a ruffled fin configuration.
Each of the layers 28 and 30 comprise a plurality of fins 50 that
are spaced apart to define passages 54 through which a cooling
medium may be flowed. Each of the example fins 50 comprises a
surface 52 that includes a wavy or undulating surface referred to
as a ruffle. The ruffled surface defines walls for the passages 54.
The undulated surface 52 defines a tortuous path for cooling medium
that enhance the cooling efficiency of the example cooling plate
assembly 10. Moreover, with the ruffled undulating configuration of
the example finned layers 28, 30 increases the surface area
available for dissipation of heat and communicating the heat
between the plurality of fins 50 and a cooling medium that flows
there through. Although finned layers 28, 30 having ruffled
configuration are shown by way of example, other fin configurations
are within the contemplation of this disclosure. As appreciated,
the cooling medium can includes air, liquid, or gas as is required
for a specific application.
[0023] Referring to FIG. 5 with continued reference to FIGS. 2 and
3, the example heat spreader assembly 20 includes a top skin 22 and
a bottom skin 26 that sandwiches a middle skin 24 there between.
Each of the top and bottom skins 22, 26 are fabricated of a
brazeable material. The middle skin 24 of the example heat spreader
assembly is fabricated from an APG material. The APG material
provides for the dissipation and spreading of heat in a direction
that is perpendicular to a thickness of the heat spreader
assembly.
[0024] The brazed joint 46 between the heat spreader assembly and
the remainder of the cold plate assembly 10 provides a less
restrictive thermal conduit through which heat may be dissipated
from the mounting surface 14 through the top or first parting sheet
38 into the fin sections 28, 30 where the heat may be carried off
by a flow of cooling medium indicated at 58 in FIG. 1.
[0025] Referring to FIGS. 2 and 3, the example cold plate assembly
10 is assembled by mounting the layer of fins 28, 30 to first and
second sides of the middle sheet 36. Each of the layers of fins 28,
30 are then surround by closure bars 32, 34 to define a boundary
for cooling medium. In the disclosed example, the fin sections 28,
30 comprise ruffled fins that have an undulating surface. Onto each
side of the fin layers 28, 30 is brazed and attached parting sheets
38, 40 to define and passages through the fin sections 28, 30 by
closing off one side of the passages 54 through the fins 50. In
this example, the top (first) parting sheet 38 is attached
utilizing a brazed joint 48 to a top surface of the closure bar 32
and the accompanying fin layer 28. A corresponding bottom (second)
sheet 40 is attached through brazed joint 48 to the closure bar 34
and over the fin layer 30.
[0026] The example heat spreader assembly 20 is assembled as a
separate unit by attaching the upper skin 22 and the lower skin 26
to the middle layer 24. The attachment may be performed utilizing
welding, brazing, or any other attachment means as is known. Once
the heat spreader assembly 20 is completed it is mounted by way of
the brazed joint 46 to the partially assembled parts to complete
the example cold plate assembly 10. All of the joints are brazed to
provide the desired fluid tightness and thermal conductivity.
[0027] The example cold plate assembly 10 includes the heat
spreader assembly 20 that defines the mounting surface 14 and
provides an improved thermal conduction of heat away from the heat
generating devices 12. The example cold plate assembly 10 with the
heat spreading assembly 20 spreads heat throughout the area of the
mounting surface 14 produced by the heat generating devices 12 to
reduce non-uniform thermal gradients across the cold plate assembly
10. Utilizing the example heat spreader assembly 20, the thermal
gradient across the mounting surface 14 of the cold plate assembly
10 is substantially uniform and improves thermal conductivity and
cooling provided by the cold plate assembly.
[0028] Although an example embodiment has been disclosed, a worker
of ordinary skill in this art would recognize that certain
modifications would come within the scope of this disclosure. For
that reason, the following claims should be studied to determine
the scope and content of this disclosure.
* * * * *