U.S. patent application number 10/826432 was filed with the patent office on 2005-10-20 for methods and apparatus for fabricating gas turbine engine combustors.
Invention is credited to Cooper, James Neil, De Vane, Shaun Michael, Fortuna, Douglas Marti, Held, Timothy James, Kastrup, David Allen, Martini, Jeffrey Michael.
Application Number | 20050229600 10/826432 |
Document ID | / |
Family ID | 34940817 |
Filed Date | 2005-10-20 |
United States Patent
Application |
20050229600 |
Kind Code |
A1 |
Kastrup, David Allen ; et
al. |
October 20, 2005 |
Methods and apparatus for fabricating gas turbine engine
combustors
Abstract
A method facilitates fabricating a gas turbine engine combustor.
The method comprises coupling a venturi to a primary swirler, and
coupling the venturi to a secondary swirler such that a gap is
defined between a portion of the venturi and a portion of one of
the primary swirler and the secondary swirler.
Inventors: |
Kastrup, David Allen; (West
Chester, OH) ; Martini, Jeffrey Michael; (Liberty
Township, OH) ; Fortuna, Douglas Marti; (Cincinnati,
OH) ; Held, Timothy James; (Blanchester, OH) ;
De Vane, Shaun Michael; (Cincinnati, OH) ; Cooper,
James Neil; (Hamilton, OH) |
Correspondence
Address: |
JOHN S. BEULICK
C/O ARMSTRONG TEASDALE LLP
ONE METROPOLITAN SQUARE
SUITE 2600
ST. LOUIS
MO
63102-2740
US
|
Family ID: |
34940817 |
Appl. No.: |
10/826432 |
Filed: |
April 16, 2004 |
Current U.S.
Class: |
60/748 |
Current CPC
Class: |
F23D 2211/00 20130101;
F23R 3/14 20130101 |
Class at
Publication: |
060/748 |
International
Class: |
F23R 003/14 |
Claims
What is claimed is:
1. A method for fabricating a gas turbine engine combustor, said
method comprising: coupling a venturi to a primary swirler; and
coupling the venturi to a secondary swirler such that a gap is
defined between a portion of the venturi and a portion of one of
the primary swirler and the secondary swirler.
2. A method in accordance with claim 1 wherein coupling the venturi
to a secondary swirler comprises coupling the venturi to the
secondary swirler such the venturi is coupled between the primary
and secondary swirlers and such that a slide fit is defined between
at least a portion of the venturi and a portion of one of the
primary and secondary swirlers.
3. A method in accordance with claim 1 wherein coupling the venturi
to a secondary swirler comprises coupling the venturi to one of the
primary swirler and the secondary swirler using at least one of a
brazing operation and a welding operation.
4. A method in accordance with claim 1 wherein one of the primary
swirler and the secondary swirler defines a flow passage extending
therethrough, said method further comprises forming a plurality of
openings extending in flow communication between the flow passage
and the gap.
5. A method in accordance with claim 1 further comprising coating
the portion of the venturi defining the gap with a thermal barrier
coating.
6. A method in accordance with claim 1 wherein coupling the venturi
to a secondary swirler further comprises coupling the venturi to
the secondary swirler such that the venturi extends between the
primary and secondary swirlers.
7. A combustor for a gas turbine engine, said combustor comprising:
a venturi; and a secondary swirler extending circumferentially
around said venturi, said secondary swirler coupled to said venturi
such that a gap is defined between a portion of said secondary
swirler and said venturi.
8. A combustor in accordance with claim 7 further comprising a
primary swirler coupled to said venturi such that said venturi is
between said primary and secondary swirlers.
9. A combustor in accordance with claim 8 wherein at least a
portion of said venturi is slidably coupled to a portion of one of
said primary and said secondary swirlers.
10. A combustor in accordance with claim 8 wherein at least a
portion of said venturi is coupled to a portion of one of said
primary and said secondary swirlers in a slide fit, said slide fit
facilitates accommodating thermal growth of at least one of said
primary and said secondary swirler with respect to said
venturi.
11. A combustor in accordance with claim 7 wherein said secondary
swirler comprises a secondary air passage extending therethrough
and a plurality of openings, said openings couple said secondary
air passage and said gap in flow communication.
12. A combustor in accordance with claim 7 wherein said gap is
defined between a radially outer surface of said venturi and a
radially inner surface of said secondary swirler, said venturi
radially outer surface comprises a layer of thermal barrier
coating.
13. A combustor in accordance with claim 7 wherein said gap
facilitates reducing an operating temperature of said venturi.
14. A gas turbine engine comprising a combustor comprising at least
one annular air swirler and an annular venturi, said annular air
swirler coupled to said venturi such that a gap is defined between
a portion of said air swirler and said venturi.
15. A gas turbine engine in accordance with claim 14 wherein said
gap facilitates reducing an operating temperature of said
venturi.
16. A gas turbine engine in accordance with claim 14 wherein at
least a portion of said at least one annular air swirler is coupled
in a slide fit against said venturi.
17. A gas turbine engine in accordance with claim 14 wherein said
air swirler defines a flow passageway extending therethrough, said
at least one air swirler comprises a plurality of openings
extending in flow communication between said flow passageway and
said gap.
18. A gas turbine engine in accordance with claim 14 wherein said
gap facilitates maintaining an operating temperature of said
venturi below a predetermined temperature.
19. A gas turbine engine in accordance with claim 14 wherein said
gap facilitates reducing coking of said venturi.
20. A gas turbine engine in accordance with claim 14 wherein said
at least one air swirler comprises a primary swirler and a
secondary swirler, said venturi coupled between said primary and
secondary swirlers.
Description
BACKGROUND OF THE INVENTION
[0001] This application relates generally to gas turbine engines
and, more particularly, to combustors for gas turbine engine.
[0002] Combustors are used to ignite fuel and air mixtures in gas
turbine engines. Known combustors include at least one dome
attached to a combustor liner that defines a combustion zone. Fuel
injectors are attached to the combustor in flow communication with
the dome and supply fuel to the combustion zone. Fuel enters the
combustor through a dome assembly attached to a spectacle or dome
plate.
[0003] At least some known dome assemblies include an air swirler
that is secured to the dome plate, and is radially outward from a
venturi. The venturi is divergent and facilitates mixing the air
and fuel, and spreading the mixture radially outwardly into the
combustion zone.
[0004] To facilitate nitrous oxide (NO.sub.x) abatement, water is
injected into at least some known gas turbine engine combustors.
However, continued operation with water injection may cause
material degradation and/or erosion of the combustor venturi. More
specifically, because the water and fuel are typically sprayed
through the combustor venturi, as the water contacts the venturi,
the high operating temperatures of the water may cause the water to
quickly change from a liquid to steam in an effect known as
"explosive boiling". Over time, such explosive boiling may lead to
material degradation and/or removal at the point of impact between
the water and the venturi. To facilitate reducing the effects of
the water injection, at least some known combustor venturis are
coated with a ceramic coating. Although such coatings may decrease
the effect of the water injection, such coatings also increase the
fabrication time and costs.
BRIEF SUMMARY OF THE INVENTION
[0005] In one embodiment, a method for fabricating a gas turbine
engine combustor is provided. The method comprises coupling a
venturi to a primary swirler, and coupling the venturi to a
secondary swirler such that a gap is defined between a portion of
the venturi and a portion of one of the primary swirler and the
secondary swirler.
[0006] In another embodiment, a combustor for a gas turbine engine
is provided. The combustor includes a venturi and a secondary
swirler extending circumferentially around the venturi. The
secondary swirler is coupled to the venturi such that a gap is
defined between a portion of the secondary swirler and the
venturi.
[0007] In a further embodiment, a gas turbine engine is provided.
The gas turbine engine includes a combustor including at least one
annular air swirler and an annular venturi. The annular air swirler
is coupled to the venturi such that a gap is defined between a
portion of the air swirler and the venturi.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a schematic illustration of a gas turbine
engine;
[0009] FIG. 2 is a cross-sectional view of a portion of a combustor
that may be used with the gas turbine engine shown in FIG. 1;
and
[0010] FIG. 3 is a cross-sectional view of a portion of an
alternative embodiment of a combustor that may be used with the gas
turbine engine shown in FIG. 1.
DETAILED DESCRIPTION OF THE INVENTION
[0011] FIG. 1 is a schematic illustration of a gas turbine engine
10 including a low pressure compressor 12, a high pressure
compressor 14, and a combustor 16. Engine 10 also includes a high
pressure turbine 18 and a low pressure turbine 20. Combustor 16
includes an upstream side 22, and at least one dome (not shown). In
one embodiment, the gas turbine engine is a LMS 100 engine
commercially available from General Electric Company, Cincinnati,
Ohio.
[0012] In operation, air flows through low pressure compressor 12
and compressed air is supplied from low pressure compressor 12 to
high pressure compressor 14. The highly compressed air is delivered
to combustor 16. Airflow (not shown in FIG. 1) from combustor 16
drives turbines 18 and 20.
[0013] FIG. 2 is a cross-sectional view of a portion of a
combustor, such as combustor 16, that may be used with gas turbine
engine 10. Combustor 16 includes a plurality of swirler assemblies
30, each of which includes a primary swirler 32, a secondary
swirler 34, and a venturi 36 that is coupled to primary and
secondary swirlers 32 and 34, respectively. Primary swirler 32,
secondary swirler 34, and venturi 36 are each co-axially aligned
with an axial centerline 38 of swirler assembly 30.
[0014] Primary swirler 32 includes a substantially cylindrical body
40 defined by an outer perimeter 42, an inner surface 44, and an
outer surface 46. A radial opening 48 extends between inner and
outer surfaces 44 and 46, respectively. Outer surface 46 faces
upstream, and inner surface 44 faces downstream when primary
swirler 32 is coupled within combustor 16. A plurality of swirl
vanes 50 extend circumferentially around opening 48 and extend
between inner surface 44 and venturi 36. In an alternative
embodiment, swirl vanes 50 extend between a radially outer, or
upstream, wall 52 and a radially inner, or downstream, wall (not
shown). In the exemplary embodiment, primary swirl vanes 50 are
spaced equidistantly apart and are oriented to induce a swirling
action to a fuel/air mixture passing through swirler assembly
30.
[0015] Secondary swirler 34 includes an inner wall 60, an outer
wall 62, and a flow passage 64 extending therebetween. In the
exemplary embodiment, secondary swirler 34 is a two-piece assembly
including inner wall 60 and outer wall 62. Alternatively, secondary
swirler 34 may be an integrally-formed single piece assembly. Flow
passage 64 has an upstream end 66 and a downstream end 68. Inner
and outer walls 60 and 62, respectively, extend circumferentially
around axial centerline 38 of swirler assembly 30. A flange portion
70 of secondary swirler 34 extends a distance 72 radially outward
from flow passage upstream end 66, such that an outer perimeter 74
of flange portion 70 is substantially aligned with primary swirler
outer perimeter 42. Flange portion 70 is in flow communication with
flow passage 64 such that air is supplied to flow passage 64
through flange portion 70.
[0016] A plurality of swirl vanes 80 extend from an inner surface
82 of outer wall 62 to an inner surface 84 of inner wall 60. In the
exemplary embodiment, inner and outer walls 60 and 62,
respectively, are coupled together by brazing or welding secondary
swirl vanes 80 to inner wall 60. In an alternative embodiment,
outer wall 62 and inner wall 60 are formed integrally together and
secondary swirl vanes 80 extend therebetween. In the exemplary
embodiment, secondary swirl vanes 80 are spaced equidistantly apart
and are oriented to induce a swirling action to air channeled
through flow passage 64. In the exemplary embodiment, primary and
secondary swirl vanes 50 and 80 are oriented in opposing
directions, such that creating opposing swirl flows are created to
facilitate mixing the fuel/air mixture when the secondary airflow
and the primary airflow are combined. In an alternative embodiment,
primary and secondary swirl vanes 50 and 80 are oriented in the
same general direction, such that a similar swirl flow is created
in the fuel/air mixture.
[0017] Venturi 36 includes a substantially annular body 90 that has
an inner surface 92 and an outer surface 94 that extends from an
upstream end 96 of venturi 36 to a downstream end 98 of venturi 36.
Venturi 36 includes a flange portion 100 positioned adjacent
upstream end 96, and a throat portion 102 that extends from flange
portion 100 to downstream end 98. Throat portion 102 extends
substantially axially along swirler assembly axial centerline 38,
and flange portion 100 extends radially outward a distance 106 from
throat portion 102 such that an outer perimeter 108 of venturi
flange portion 100 is generally aligned with primary swirler and
secondary swirler outer perimeters 42 and 74, respectively.
[0018] In the exemplary embodiment, venturi flange portion 100
extends between primary swirler 32 and secondary swirler 34, such
that venturi inner surface 92 is coupled against primary swirl
vanes 50, and such that venturi outer surface 94 is coupled against
an outer surface 110 of secondary swirler inner wall 60. In an
alternative embodiment, inner surface 92 is coupled against primary
swirler inner wall (not shown). More specifically, in the exemplary
embodiment, flange portion 100 is coupled to primary and secondary
swirlers 32 and 34, respectively, by a brazing operation or a
welding operation.
[0019] Venturi 36 extends downstream from primary swirler 32 such
that airflow discharged from swirler 32 is channeled through
venturi 36 which induces a swirling action to the airflow passing
therethrough. Specifically, airflow discharged into venturi 36 is
channeled by flange portion 100 into throat portion 102. Throat
portion 102 has a converging-diverging cross sectional profile that
extends from flange portion 100 to downstream end 98 such that a
minimum throat diameter D.sub.1 is located a distance 112 upstream
from downstream end 98. Accordingly, throat diameter D.sub.1 is
smaller than a diameter D.sub.2 of primary swirler opening 48 and
is smaller than a diameter D.sub.3 of venturi 36 at downstream end
98.
[0020] Secondary swirler 34 circumscribes venturi throat portion
102, and a portion of throat portion 102 is coupled to secondary
swirler 34. Specifically, a portion 114 of venturi outer surface 94
is coupled to a portion 116 of secondary swirler inner wall outer
surface 110 in a slide fit. The slide fit connection created
between venturi 36 and secondary swirler 34 facilitates venturi 36
accommodating thermal expansion of secondary swirler 34, and also
facilitates preventing ingestion of fuel, water and air between
venturi 36 and secondary swirler 34 at downstream end 98. In an
alternative embodiment, venturi downstream end 98 is coupled to
secondary swirler 34 by a brazing or welding operation.
[0021] A gap 120 is partially defined between venturi outer surface
94 and secondary swirler inner wall 60. In the exemplary
embodiment, gap 120 extends from venturi and secondary swirler
flange portions 36 and 34, respectively, towards venturi downstream
end 98 where venturi 36 and secondary swirler 34 are fixedly
coupled together. Gap 120 creates a dead air cavity between venturi
36 and secondary swirler flow passage 64, which facilitates
insulating venturi 36 from high temperatures associated with flow
passage 64. Accordingly, gap 120 also facilitates reducing a rate
of "explosive boiling" on venturi outer surface 94, thereby
minimizing the need for a ceramic coating on venturi outer surface.
However, in an alternative embodiment, venturi outer surface 94 is
coated with a ceramic coating. In another alternative embodiment,
venturi inner and/or outer surface 92 and/or 94 is coated with a
thermal barrier coating to facilitate insulating venturi 36 from
high temperatures.
[0022] In the exemplary embodiment, a plurality of openings 122
extend through secondary swirler inner wall 60 to couple flow
passage 64 and gap 120 in flow communication. Openings 122 enable
bleed air flowing through passage 64 to enter gap 120 to facilitate
providing a purge flow through gap 120. The purge flow facilitates
preventing the ingestion of fuel, water and air into gap 120. In an
alternative embodiment, no openings are provided between flow
passage 64 and gap 120.
[0023] In the exemplary embodiment, the individual components of
swirler assembly 30, such as primary swirler 32, secondary swirler
34, and venturi 36 are manufactured and fabricated from different
materials to facilitate optimizing wear and performance
characteristics. For example, primary swirler 32 is fabricated from
a material selected to facilitate optimizing wear, and secondary
swirler 34 is fabricated from a different material that is selected
to facilitate optimizing thermal characteristics and bonding with
venturi 36. Moreover, venturi 36 is fabricated from a material
selected to facilitate optimizing wear characteristics in the
presence of sprayed fuel and water and to facilitate bonding with
primary and secondary swirlers 32 and 34, respectively.
[0024] During operation, the air/fuel mixture is channeled
downstream through swirler assembly 30. As the mixture is channeled
through primary swirler opening 48, the mixture is combined with
swirling air from primary swirler 32. The swirling action
facilitates spreading the mixture radially outward from swirler
assembly 30 into the combustion zone. As the mixture is channeled
from the swirler assembly 30, it is further mixed with air supplied
by secondary swirler flow passage 64.
[0025] FIG. 3 is a cross-sectional view of an alternative
embodiment of a swirler assembly 130 that may be used in
combination with a combustor, such as combustor 16 (shown in FIG.
1). Swirler assembly 130 is substantially similar to swirler
assembly 30 shown in FIG. 2, and components in swirler assembly 130
that are identical to components of swirler assembly 130 are
identified in FIG. 3 using the same reference numerals used in FIG.
2. Accordingly, swirler assembly 130 includes primary swirler 32,
secondary swirler 34, and venturi 36.
[0026] Primary swirler 32 includes radially outer wall 52, a
radially inner wall 140, and a radial opening 142 extending between
inner and outer walls 140 and 52, respectively. Each wall 52 and
140 has an inner surface 144 and 146, respectively, an outer
surface 148 and 150, respectively, and an outer perimeter 152 and
154, respectively, extending therebetween. Outer surfaces 148 and
150 face upstream, and inner surfaces 144 and 146 face downstream
when primary swirler 32 is properly positioned in combustor 16.
Swirl vanes 50 extend circumferentially around opening 142 and
extend between outer wall 140 and inner wall 52.
[0027] Secondary swirler 34 includes inner wall 60, outer wall 62,
and flow passage 64 extending therebetween. In the exemplary
embodiment, secondary swirler inner wall 60 has a ridge 160
extending outwardly towards primary swirler 32, and primary swirler
inner wall 52 has an upper shoulder 162 for engaging ridge 160.
Swirl vanes 80 extend within flange portion 70 from inner wall
inner surface 84 to outer wall inner surface 82. Flange portion 70
is in flow communication with flow passage 64 such that air is
supplied to flow passage 64 through flange portion 70.
[0028] Venturi 36 includes body 90 that has inner surface 92 and
outer surface 94 that extends from upstream end 96 to downstream
end 98. Venturi 36 includes a flange portion 170 extending from
throat portion 102 at upstream end 96. Flange portion 170 extends a
distance 172 radially outward from throat portion 102 such that an
outer perimeter 174 of venturi flange portion 170 is positioned
between primary swirler 32 and secondary swirler 34. In the
exemplary embodiment, venturi outer perimeter 174 abuts a bottom
edge 176 of ridge 160 extending from secondary swirler inner wall
60 and abuts a lower shoulder 178 of primary swirler inner wall 52.
Specifically, venturi flange portion 170 is coupled against primary
swirler 32 and secondary swirler 34 in a slide fit. The slide fit
connection created between venturi 36 and primary and secondary
swirlers 32 and 34, respectively, facilitates venturi 36
accommodating thermal expansion of swirlers 32 and 34, and also
facilitates preventing ingestion of fuel, water and/or air between
venturi 36 and swirlers 32 and/or 34. In an alternative embodiment,
venturi flange portion 170 is coupled to primary and/or secondary
swirlers 32 and/or 34, respectively, by a brazing or welding
operation.
[0029] Secondary swirler 34 circumscribes venturi throat portion
102, and a portion 180 of throat portion 102 is coupled to
secondary swirler 34. Specifically, venturi outer surface portion
114 is coupled to secondary swirler inner wall 60 at downstream end
98 by a brazing operation or a welding operation to facilitate
preventing ingestion of fuel, water and air between venturi 36 and
secondary swirler 34. In an alternative embodiment, outer surface
94 is coupled to inner wall 60 via a slide fit connection.
[0030] Gap 120 is partially defined between venturi outer surface
94 and secondary swirler inner wall 60. In the exemplary
embodiment, gap 120 extends from venturi and secondary swirler
flange portions 70 and 170, respectively, towards venturi
downstream end 98 where venturi 36 and secondary swirler 34 are
fixedly coupled together. In the exemplary embodiment, openings 122
extend between flow passage 64 and gap 120 so that flow passage 64
and gap 120 are in flow communication. In an alternative
embodiment, no openings are provided between flow passage 64 and
gap 120.
[0031] The above-described combustor system for a gas turbine
engine is cost-effective and reliable. The combustor system
includes a multi component swirler assembly that includes a primary
swirler, a secondary swirler and a venturi. A dead air gap is
provided between the venturi and at least one of the swirlers which
facilitates cooling the venturi, and openings are provided between
the venturi and the air flow passage such that the air gap and the
flow passage are in flow communication. Furthermore, because the
components are slide fit together, the components facilitate
allowing thermal expansion to occur therebetween. As a result, the
swirler assembly facilitates extending a useful life of the
combustor in a reliable and cost-effective manner.
[0032] Exemplary embodiments of swirler assemblies are described
above in detail. The assemblies are not limited to the specific
embodiments described herein, but rather, components of each
assembly may be utilized independently and separately from other
components described herein. Each swirler assembly component can
also be used in combination with other swirler assembly
components.
[0033] While the invention has been described in terms of various
specific embodiments, those skilled in the art will recognize that
the invention can be practiced with modification within the spirit
and scope of the claims.
* * * * *