U.S. patent application number 16/807478 was filed with the patent office on 2020-12-03 for backside features with intermitted pin fins.
The applicant listed for this patent is United Technologies Corporation. Invention is credited to John W. Mubeezi, Steven D. Porter.
Application Number | 20200378602 16/807478 |
Document ID | / |
Family ID | 1000005218633 |
Filed Date | 2020-12-03 |
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United States Patent
Application |
20200378602 |
Kind Code |
A1 |
Porter; Steven D. ; et
al. |
December 3, 2020 |
BACKSIDE FEATURES WITH INTERMITTED PIN FINS
Abstract
A method of manufacturing a heat shield panel including pouring
melted wax into a negative pattern of the heat shield panel, the
heat shield panel including first pin fins with rounded tops and
second pin fins with flat tops; allowing the wax to solidify to
form a positive pattern of the heat shield panel; removing the
positive pattern from the negative pattern by using an ejector rod
to push the positive pattern away from the negative pattern at the
flat top of each of the one or more second pin fins; coating the
positive pattern with a ceramic; melting the positive pattern away
from the ceramic, the ceramic having a cavity forming a second
negative pattern of the heat shield panel; pouring melted metal
into the cavity; allowing metal in the cavity to cool to form the
heat shield panel; and removing the ceramic from the heat shield
panel.
Inventors: |
Porter; Steven D.;
(Wethersfield, CT) ; Mubeezi; John W.; (Vernon,
CT) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
United Technologies Corporation |
Farmington |
CT |
US |
|
|
Family ID: |
1000005218633 |
Appl. No.: |
16/807478 |
Filed: |
March 3, 2020 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
15686344 |
Aug 25, 2017 |
10619852 |
|
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16807478 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F23R 3/005 20130101;
B22C 7/02 20130101; F23R 2900/03044 20130101; F23R 3/002 20130101;
F23M 5/085 20130101 |
International
Class: |
F23R 3/00 20060101
F23R003/00; B22C 7/02 20060101 B22C007/02 |
Claims
1. A method of manufacturing a heat shield panel, the method
comprising: pouring melted wax into a negative pattern of the heat
shield panel, the heat shield panel comprising: a panel body having
a first surface configured to be oriented toward a combustion zone
of a combustor, and a second surface opposite the first surface,
the second surface being configured to be oriented toward a
combustor liner of the combustor; a plurality of first pin fins
projecting from the second surface of the panel body, wherein each
of the plurality of first pin fins has a rounded top opposite the
second surface; and one or more second pin fins projecting from the
second surface of the panel body, wherein each of the one or more
second pin fins has a flat top opposite the second surface;
allowing the wax to solidify to form a positive pattern of the heat
shield panel; removing the positive pattern from the negative
pattern by using an ejector rod to push the positive pattern away
from the negative pattern at the flat top of each of the one or
more second pin fins; coating the positive pattern with a ceramic;
melting the positive pattern away from the ceramic, the ceramic
having a cavity forming a second negative pattern of the heat
shield panel; pouring melted metal into the cavity; allowing metal
in the cavity to cool to form the heat shield panel; and removing
the ceramic from the heat shield panel.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Divisional Application of U.S.
Non-Provisional application Ser. No. 15/686,344 filed Aug. 25,
2017, the disclosure of which is incorporated herein by reference
in its entirety.
BACKGROUND
[0002] The subject matter disclosed herein generally relates to
combustors in gas turbine engines and, more particularly, to heat
shield panels in combustors of gas turbine engines.
[0003] A combustor of a gas turbine engine may be configured and
required to burn fuel in a minimum volume. Such configurations may
place substantial heat load on the structure of the combustor
(e.g., panels, shell, etc.). Such heat loads may dictate that
special consideration is given to structures which may be
configured as heat shields or panels configured to protect the
walls of the combustor. Even with such configurations, excess
temperatures at various locations may occur leading to oxidation,
cracking, and high thermal stresses of the heat shields or panels.
Manufacturing of heat shield panels is a difficult process and
improvements to the manufacturing process are greatly desired.
SUMMARY
[0004] According to one embodiment, a heat shield panel for a
combustor of a gas turbine engine is provided. The heat shield
comprising: a panel body having a first surface configured to be
oriented toward a combustion zone of a combustor, and a second
surface opposite the first surface, the second surface being
configured to be oriented toward a combustor liner of the
combustor; a plurality of first pin fins projecting from the second
surface of the panel body, wherein each of the plurality of first
pin fins has a rounded top opposite the second surface; and one or
more second pin fins projecting from the second surface of the
panel body, wherein each of the one or more second pin fins has a
flat top opposite the second surface.
[0005] In addition to one or more of the features described above,
or as an alternative, further embodiments may include that the one
or more second pin fins are intermittently spaced amongst the
plurality of first pin fins.
[0006] In addition to one or more of the features described above,
or as an alternative, further embodiments may include that the one
or more second pin fins are separated from each other by about 0.5
inches (1.27 centimeters).
[0007] In addition to one or more of the features described above,
or as an alternative, further embodiments may include that the flat
top of each of the one or more second pin fins is about parallel to
the second surface where each of the one or more second pin fins
are located.
[0008] In addition to one or more of the features described above,
or as an alternative, further embodiments may include that each of
the plurality of first pin fins are about equal in height.
[0009] In addition to one or more of the features described above,
or as an alternative, further embodiments may include that each of
the plurality of first pin fins have a height equal to about 0.023
inches (0.058 centimeters).
[0010] In addition to one or more of the features described above,
or as an alternative, further embodiments may include that each of
the plurality of first pin fins further comprises a first radius
located proximate the second surface and a second radius located
proximate the rounded top, and wherein the first radius is
different from the second radius.
[0011] In addition to one or more of the features described above,
or as an alternative, further embodiments may include that the
first radius is larger than the second radius.
[0012] In addition to one or more of the features described above,
or as an alternative, further embodiments may include that the
first radius is about equal to 0.015 inches (0.0381
centimeters).
[0013] In addition to one or more of the features described above,
or as an alternative, further embodiments may include that the
second radius is about equal to 0.0125 inches (0.03175
centimeters).
[0014] In addition to one or more of the features described above,
or as an alternative, further embodiments may include that each of
the plurality of first pin fins further comprises a diameter, and
wherein a ratio of the height to the diameter is about equal to
0.8.
[0015] In addition to one or more of the features described above,
or as an alternative, further embodiments may include that each of
the one or more second pin fins further includes a radius about
equal to a radius of each of the plurality of first pin fins.
[0016] In addition to one or more of the features described above,
or as an alternative, further embodiments may include that each of
the one or more second pin fins further includes a radius greater
than a radius of each of the plurality of first pin fins.
[0017] In addition to one or more of the features described above,
or as an alternative, further embodiments may include one or more
third pin fins projecting from the second surface of the panel
body, wherein each of the one or more third pin fins has a flat top
opposite the second surface.
[0018] In addition to one or more of the features described above,
or as an alternative, further embodiments may include that each of
the one or more third pin fins are located proximate one of the one
or more second pin fins.
[0019] In addition to one or more of the features described above,
or as an alternative, further embodiments may include connectors to
connect the panel body to the combustor liner.
[0020] In addition to one or more of the features described above,
or as an alternative, further embodiments may include that each of
the plurality of first pin fins are cylindrical in shape.
[0021] In addition to one or more of the features described above,
or as an alternative, further embodiments may include that each of
the one or more second pin fins are cylindrical in shape.
[0022] According to another embodiment, a combustor for a gas
turbine engine is provided. The combustor for a gas turbine engine
comprising: a combustor liner defining a combustion volume; and at
least one heat shield panel comprising: a panel body having a first
surface configured to be oriented toward a combustion zone of the
combustor, and a second surface opposite the first surface, the
second surface being configured to be oriented toward the combustor
liner of the combustor; a plurality of first pin fins projecting
from the second surface of the panel body, wherein each of the
plurality of first pin fins has a rounded top opposite the second
surface; and one or more second pin fins projecting from the second
surface of the panel body, wherein each of the one or more second
pin fins has a flat top opposite the second surface.
[0023] According to another embodiment, a method of manufacturing a
heat shield panel, the method comprising: pouring melted wax into a
negative pattern of the heat shield panel, the heat shield panel
comprising: a panel body having a first surface configured to be
oriented toward a combustion zone of a combustor, and a second
surface opposite the first surface, the second surface being
configured to be oriented toward a combustor liner of the
combustor; a plurality of first pin fins projecting from the second
surface of the panel body, wherein each of the plurality of first
pin fins has a rounded top opposite the second surface; and one or
more second pin fins projecting from the second surface of the
panel body, wherein each of the one or more second pin fins has a
flat top opposite the second surface; allowing the wax to solidify
to form a positive pattern of the heat shield panel; removing the
positive pattern from the negative pattern by using an ejector rod
to push the positive pattern away from the negative pattern at the
flat top of each of the one or more second pin fins; coating the
positive pattern with a ceramic; melting the positive pattern away
from the ceramic, the ceramic having a cavity forming a second
negative pattern of the heat shield panel; pouring melted metal
into the cavity; allowing metal in the cavity to cool to form the
heat shield panel; and removing the ceramic from the heat shield
panel.
[0024] The foregoing features and elements may be combined in
various combinations without exclusivity, unless expressly
indicated otherwise. These features and elements as well as the
operation thereof will become more apparent in light of the
following description and the accompanying drawings. It should be
understood, however, that the following description and drawings
are intended to be illustrative and explanatory in nature and
non-limiting.
BRIEF DESCRIPTION
[0025] The following descriptions should not be considered limiting
in any way. With reference to the accompanying drawings, like
elements are numbered alike:
[0026] FIG. 1 is a partial cross-sectional illustration of a gas
turbine engine, in accordance with an embodiment of the
disclosure;
[0027] FIG. 2 is a cross-sectional illustration of a combustor, in
accordance with an embodiment of the disclosure;
[0028] FIG. 3 is an illustration of a heat shield panel, in
accordance with an embodiment of the disclosure;
[0029] FIG. 4 is an illustration of a heat shield panel, in
accordance with an embodiment of the disclosure;
[0030] FIG. 5 is an illustration of a heat shield panel, in
accordance with an embodiment of the disclosure; and
[0031] FIG. 6 is a flow chart illustrating a method of
manufacturing a heat shield panel for a combustor of a gas turbine
engine, in accordance with an embodiment of the disclosure.
[0032] The detailed description explains embodiments of the present
disclosure, together with advantages and features, by way of
example with reference to the drawings.
DETAILED DESCRIPTION
[0033] A detailed description of one or more embodiments of the
disclosed apparatus and method are presented herein by way of
exemplification and not limitation with reference to the
Figures.
[0034] Combustors of gas turbine engines experience elevated heat
levels during operation. Impingement and convective cooling of
panels of the combustor wall may be used to help cool the
combustor. Convective cooling may be achieved by air that is
trapped between the panels and a shell of the combustor.
Impingement cooling may be a process of directing relatively cool
air from a location exterior to the combustor toward a back or
underside of the panels.
[0035] Thus, combustor liners and heat shields are utilized to face
the hot products of combustion within a combustion chamber and
protect the overall combustor shell. The combustor liners may be
supplied with cooling air including dilution passages which deliver
a high volume of cooling air into a hot flow path. The cooling air
may be air from the compressor of the gas turbine engine. The
cooling air may impinge upon a back side of a heat shield panel
that faces a combustor liner inside the combustor. In order to
increase surface area of the heat shield panel and thus also
increase cooling, the back side of the heat shield panel may
include pin fins that extend away from the panel. The pin fins
introduces challenges into the manufacturing process, which is
typically done by investment casting. The pin fins inhibit the
removal for a wax mold from a negative mold of the heat shield
panel. Embodiments disclosed herein include apparatuses and methods
to aid in the removal of a wax mold from a negative mold of the
heat shield panel during the investment casting manufacturing
process.
[0036] FIG. 1 schematically illustrates a gas turbine engine 20.
The gas turbine engine 20 is disclosed herein as a two-spool
turbofan that generally incorporates a fan section 22, a compressor
section 24, a combustor section 26 and a turbine section 28.
Alternative engines might include an augmentor section (not shown)
among other systems or features. The fan section 22 drives air
along a bypass flow path B in a bypass duct, while the compressor
section 24 drives air along a core flow path C for compression and
communication into the combustor section 26 then expansion through
the turbine section 28. Although depicted as a two-spool turbofan
gas turbine engine in the disclosed non-limiting embodiment, it
should be understood that the concepts described herein are not
limited to use with two-spool turbofans as the teachings may be
applied to other types of turbine engines including three-spool
architectures.
[0037] The exemplary engine 20 generally includes a low speed spool
30 and a high speed spool 32 mounted for rotation about an engine
central longitudinal axis A relative to an engine static structure
36 via several bearing systems 38. It should be understood that
various bearing systems 38 at various locations may alternatively
or additionally be provided, and the location of bearing systems 38
may be varied as appropriate to the application.
[0038] The low speed spool 30 generally includes an inner shaft 40
that interconnects a fan 42, a low pressure compressor 44 and a low
pressure turbine 46. The inner shaft 40 is connected to the fan 42
through a speed change mechanism, which in exemplary gas turbine
engine 20 is illustrated as a geared architecture 48 to drive the
fan 42 at a lower speed than the low speed spool 30. The high speed
spool 32 includes an outer shaft 50 that interconnects a high
pressure compressor 52 and high pressure turbine 54. A combustor
300 is arranged in exemplary gas turbine 20 between the high
pressure compressor 52 and the high pressure turbine 54. An engine
static structure 36 is arranged generally between the high pressure
turbine 54 and the low pressure turbine 46. The engine static
structure 36 further supports bearing systems 38 in the turbine
section 28. The inner shaft 40 and the outer shaft 50 are
concentric and rotate via bearing systems 38 about the engine
central longitudinal axis A which is collinear with their
longitudinal axes.
[0039] The core airflow is compressed by the low pressure
compressor 44 then the high pressure compressor 52, mixed and
burned with fuel in the combustor 300, then expanded over the high
pressure turbine 54 and low pressure turbine 46. The turbines 46,
54 rotationally drive the respective low speed spool 30 and high
speed spool 32 in response to the expansion. It will be appreciated
that each of the positions of the fan section 22, compressor
section 24, combustor section 26, turbine section 28, and fan drive
gear system 48 may be varied. For example, gear system 48 may be
located aft of combustor section 26 or even aft of turbine section
28, and fan section 22 may be positioned forward or aft of the
location of gear system 48.
[0040] The engine 20 in one example is a high-bypass geared
aircraft engine. In a further example, the engine 20 bypass ratio
is greater than about six (6), with an example embodiment being
greater than about ten (10), the geared architecture 48 is an
epicyclic gear train, such as a planetary gear system or other gear
system, with a gear reduction ratio of greater than about 2.3 and
the low pressure turbine 46 has a pressure ratio that is greater
than about five. In one disclosed embodiment, the engine 20 bypass
ratio is greater than about ten (10:1), the fan diameter is
significantly larger than that of the low pressure compressor 44,
and the low pressure turbine 46 has a pressure ratio that is
greater than about five 5:1. Low pressure turbine 46 pressure ratio
is pressure measured prior to inlet of low pressure turbine 46 as
related to the pressure at the outlet of the low pressure turbine
46 prior to an exhaust nozzle. The geared architecture 48 may be an
epicycle gear train, such as a planetary gear system or other gear
system, with a gear reduction ratio of greater than about 2.3:1. It
should be understood, however, that the above parameters are only
exemplary of one embodiment of a geared architecture engine and
that the present disclosure is applicable to other gas turbine
engines including direct drive turbofans.
[0041] A significant amount of thrust is provided by the bypass
flow B due to the high bypass ratio. The fan section 22 of the
engine 20 is designed for a particular flight condition--typically
cruise at about 0.8 Mach and about 35,000 feet (10,688 meters). The
flight condition of 0.8 Mach and 35,000 ft (10,688 meters), with
the engine at its best fuel consumption--also known as "bucket
cruise Thrust Specific Fuel Consumption (`TSFC`)"--is the industry
standard parameter of lbm of fuel being burned divided by lbf of
thrust the engine produces at that minimum point. "Low fan pressure
ratio" is the pressure ratio across the fan blade alone, without a
Fan Exit Guide Vane ("FEGV") system. The low fan pressure ratio as
disclosed herein according to one non-limiting embodiment is less
than about 1.45. "Low corrected fan tip speed" is the actual fan
tip speed in ft/sec divided by an industry standard temperature
correction of [(Tram .degree. R)/(518.7.degree. R)]0.5. The "Low
corrected fan tip speed" as disclosed herein according to one
non-limiting embodiment is less than about 1150 ft/second (350.5
m/sec).
[0042] Referring now to FIG. 2 with continued reference to FIG. 1.
FIG. 2 illustrates a combustor section 26 of a gas turbine engine
20. As shown, a combustor 300 defines a combustion chamber 302. The
combustion chamber 302 includes a combustion zone 370, as shown in
FIG. 2. The combustor 300 includes an inlet 306 and an outlet 308
through which air may pass. The air may be supplied to the
combustor 300 by a pre-diffuser 110.
[0043] As shown in FIG. 2, compressor air is supplied from a
compressor section 24 into an exit guide vane 112, as will be
appreciated by those of skill in the art. The exit guide vane 112
is configured to direct the airflow into the pre-diffuser 110,
which then directs the airflow toward the combustor 300. The
combustor 300 and the pre-diffuser 110 are separated by a shroud
chamber 113 that contains the combustor 300 and includes an inner
diameter branch 114 and an outer diameter branch 116. As air enters
the shroud chamber 113 a portion of the air may flow into the
combustor inlet 306, a portion may flow into the inner diameter
branch 114, and a portion may flow into the outer diameter branch
116.
[0044] The air from the inner diameter branch 114 and the outer
diameter branch 116 may then enter the combustion chamber 302 by
means of one or more aperture 309, which may include nozzles,
holes, etc. The air may then exit the combustion chamber 302
through the combustor outlet 308. At the same time, fuel may be
supplied into the combustion chamber 302 from a fuel injector 320
and a pilot nozzle 322, which may be ignited within the combustion
chamber 302. The combustor 300 of the engine combustion section 100
may be housed within a shroud case 124 which may define the shroud
chamber 113.
[0045] The combustor 300, as shown in FIG. 2, includes multiple
heat shield panels 400 that are mounted on an interior surface of
one or more combustion liner 330 and are arranged parallel to the
combustion liner 330. The combustion liner 330 can define circular
or annular structures with the heat shield panels 400 being mounted
on a radially inward liner and a radially outward liner, as will be
appreciated by those of skill in the art. The heat shield panels
400 can be removably mounted to the combustion liner 330 by one or
more attachment mechanisms 332. In some embodiments, the attachment
mechanism 332 may be integrally formed with a respective heat
shield panel 400, although other configurations are possible. In
some embodiments, the attachment mechanism 332 may be a bolt or
other structure that may extend from the respective heat shield
panel 400 through the interior surface to a receiving portion or
aperture of the combustion liner 330 such that the heat shield
panel 400 may be attached to the combustion liner 330 and held in
place. The heat shield panels 400 partial enclose a combustion zone
360 within the combustion chamber 302 of the combustor 300.
[0046] The heat shield panel 400 is composed of a panel body 402
having a first surface 410 and a second surface 420 opposite the
first surface 410. The first surface 410 is configured to be
oriented toward the combustion zone 370 of the combustor 300. The
second surface 420 is configured to be oriented toward a combustor
liner 330 of the combustor 300.
[0047] Referring now to FIG. 3-5 with continued reference to FIGS.
1 and 2. FIG. 3 illustrates an enlarged view of a heat shield panel
400 of the combustor 300 of a gas turbine engine 20. As discussed
above, the heat shield panel 400 is composed of a panel body 402
having a first surface 410 and a second surface 420 opposite the
first surface 410. The heat shield panel 400 further includes a
plurality of first pin fins 430 projecting from the second surface
420 of the panel body 402. Each of the plurality of first pin fins
430 has a rounded top 432 opposite the second surface 420. Each of
the plurality of first pin fins may be cylindrical in shape as seen
in FIGS. 3-4. It is understood that each of the plurality of first
pin fins 430 may have shapes other than cylindrical. The heat
shield panel 400 also includes one or more second pin fins 460
projecting from the second surface 420 of the panel body 402. Each
of the one or more second pin fins 460 has a flat top 462 opposite
the second surface 420. Each of the one or more second pin fins may
be cylindrical in shape as seen in FIGS. 3-4. It is understood that
each of the one or more second pin fins 460 may have shapes other
than cylindrical. In an embodiment, the flat top 462 of each of the
one or more second pin fins 460 is about parallel to the second
surface 420 where each of the one or more second pin fins are
located. It is understood that the second surface 420 may be
curved, thus the flat top 462 of each of the one or more second pin
fins 460 may be parallel to the second surface 420 where each of
the one or more second pin fins 460 are located. Advantageously,
having the flat top 462 parallel to the second surface 420 allows
an ejector rod to be utilized during manufacturing to provide a
force perpendicular to the second surface 420 in order to remove a
wax mold away from a negative mold of the heat shield panel 400
(discussed later in relation to method 600). A attachment mechanism
332 to connect the panel body 402 to the combustor liner 330 may be
seen in FIG. 3.
[0048] As seen in FIG. 3, the one or more second pin fins 460 are
intermittently spaced amongst the plurality of first pin fins 430.
The one or more second pin fins 460 may be spaced apart from each
other by a first selected distance D1. In an embodiment, the first
selected distance D1 may be about equal to 0.5 inches (1.27
centimeters), thus the one or more second pin fins 460 are
separated from each other by about 0.5 inches (1.27 centimeters).
In an embodiment, each of the first pin fins 430 may be equal in
height H1. The height H1 is the distance measured from the rounded
top 432 to the second surface 420, as seen in FIG. 4. In another
embodiment, each of the plurality of first pin fins 430 have a
height H1 equal to about 0.023 inches (0.058 centimeters). The
height H2 of each of the one or more second pin fins 460 may be
equal to the height H1 of each of the plurality of first pin fins
430. Moreover, each of the plurality of first pin fins 430 include
a first radius R1 located proximate the second surface 420 and a
second radius R2 located proximate the rounded top 432. As seen in
FIG. 4, the first radius R1 is different from the second radius R2.
The first radius may be larger than the second radius R2. In an
embodiment, the first radius R1 is about equal to 0.015 inches
(0.0381 centimeters). In an embodiment, the second radius R2 is
about equal to 0.0125 inches (0.03175 centimeters). Each of the
plurality of first pin fins 430 include a diameter DIAL In
embodiment, the diameter DIA1 may be about equal to 0.030. In
another embodiment, a ratio (H1/DIA1) of the height H1 to the
diameter DIA1 is about equal to 0.8.
[0049] Each of the one or more second pin fins 460 may have a
radius R3 different than a radius R1, R2 of each of the plurality
of first pin fins 430. In an embodiment, each of the one or more
second pin fins 460 may include a radius R3 about equal to a radius
R1, R2 of each of the plurality of first pin fins 430. Whereas, in
another embodiment, each of the one or more second pin fins 460
further includes a radius R3 greater than a radius R1, R2 of each
of the plurality of first pin fins 430. For example, second pin fin
460 may take up the same area of multiple first pin fins 430 on the
second surface 420. In another embodiment, panel body 402 may
include one or more third pin fins 490 projecting from the second
surface 420 of the panel body 402. Each of the one or more third
pin fins 490 has a flat top 492 opposite the second surface 420.
Each of the one or more third pin fins 490 may be located proximate
one of the one or more second pin fins 460, as seen in FIG. 5.
Advantageously, the third pin fins 490 may provide points for
additional leverage for an ejector rod during the manufacturing
process of the heat shield panel 400.
[0050] Referring now to FIG. 6 with continued reference to FIGS.
1-5. FIG. 6 is a flow chart illustrating a method 600 of
manufacturing a heat shield panel 400, according to an embodiment
of the present disclosure. At block 602, melted wax is poured into
a negative pattern of the heat shield panel 400. At block 604, the
wax is allowed to solidify to form a positive pattern of the heat
shield panel 400. At block 606, the positive pattern made from wax
is removed from the negative pattern by using an ejector rod to
push the positive pattern away from the negative pattern at the
flat top 462 of each of the one or more second pin fins 460. At
block 608, the positive pattern made from wax is coated with a
ceramic. At block 610, the positive pattern made from wax is melted
away from the ceramic, thus leaving a cavity formed in the ceramic.
The cavity forming a second negative pattern of the heat shield
panel 400. At block 612, melted metal is poured into the cavity
within the ceramic. At block 614, metal within the cavity is
allowed to cool to form the heat shield panel 400. At block 616,
the ceramic is removed from the heat shield panel 400 and what
remains is the full formed metallic heat shield panel 400.
[0051] While the above description has described the flow process
of FIG. 6 in a particular order, it should be appreciated that
unless otherwise specifically required in the attached claims that
the ordering of the steps may be varied.
[0052] Technical effects of embodiments of the present disclosure
include utilizing pin fins with flat tops spaced intermittently
amongst pin fins with round tops in order to ease the manufacturing
process of a heat shield panel for a combustor of a gas turbine
engine.
[0053] The term "about" is intended to include the degree of error
associated with measurement of the particular quantity based upon
the equipment available at the time of filing the application. For
example, "about" can include a range of .+-.8% or 5%, or 2% of a
given value.
[0054] The terminology used herein is for the purpose of describing
particular embodiments only and is not intended to be limiting of
the present disclosure. As used herein, the singular forms "a",
"an" and "the" are intended to include the plural forms as well,
unless the context clearly indicates otherwise. It will be further
understood that the terms "comprises" and/or "comprising," when
used in this specification, specify the presence of stated
features, integers, steps, operations, elements, and/or components,
but do not preclude the presence or addition of one or more other
features, integers, steps, operations, element components, and/or
groups thereof.
[0055] While the present disclosure has been described with
reference to an exemplary embodiment or embodiments, it will be
understood by those skilled in the art that various changes may be
made and equivalents may be substituted for elements thereof
without departing from the scope of the present disclosure. In
addition, many modifications may be made to adapt a particular
situation or material to the teachings of the present disclosure
without departing from the essential scope thereof. Therefore, it
is intended that the present disclosure not be limited to the
particular embodiment disclosed as the best mode contemplated for
carrying out this present disclosure, but that the present
disclosure will include all embodiments falling within the scope of
the claims.
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