TECHNICAL FIELD
[0001] This disclosure relates to gas turbine engines and, in particular, to heat shields.
BACKGROUND
[0002] In a gas turbine engine, a gap is typically left between a blade track and a nozzle
guide vane. The gap allows the blade track and the nozzle guide vane to thermally
expand during operation of the gas turbine engine without causing damage by the blade
track and the nozzle guide vane coming into contact with each other.
[0003] US 2006/245924 A1 discloses a system in a gas turbine engine in accordance with the preamble of claim
1.
[0004] US 6 076 835 A discloses a sealing member for sealing between vanes of a compressor of a gas turbine
engine. The seal includes a first annular sealing member which includes a first sealing
portion and a flange portion. The first sealing member cooperates with a second sealing
member. The first and second sealing members, upon installation, contact each other
and block an axial gap between adjacent vanes.
[0005] EP 3 095 958 A1 discloses a system for thermally shielding a portion of a shroud assembly for a gas
turbine engine. The system includes a thermal shield on a bottom portion of a forward
wall of a shroud seal support, which upon installation, prevents or restricts leakage
of combustion gases through a radial gap between the forward wall and a top surface
of a shroud seal.
US 2014/003924 A1 discusses an aircraft turbine casing configured to carry a set of ring sectors that
partly delimits a conduit inside which a gas flow passes through the turbine. An annular
jaw-grip-shaped piece is disclosed holding a radial lug of a wall of a casing against
a ring sector.
[0006] FR 3 009 739 A1 describes an assembly comprising two parts arranged one inside the other concentrically
about a turbomachine axis. A C-bracket is provided holding the two parts together.
A fixing pin is attached to one arm of the clip, fixing this arm to one of the parts.
SUMMARY
[0007] The invention provides for a system with the features of claim 1 and a method with
the features of claim 10. Embodiments of the invention are identified in the dependent
claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The embodiments may be better understood with reference to the following drawings
and description. The components in the figures are not necessarily to scale.
Moreover, in the figures, like-referenced numerals designate corresponding parts throughout
the different views.
FIG. 1 illustrates a cross-sectional view of an example of a gas turbine engine with
a close-up view of a cross section of portion of a turbine section of the gas turbine
engine;
FIG. 2 illustrates the close-up view of the cross section of the portion of the turbine
section of the gas turbine engine as shown in FIG. 1;
FIG. 3 illustrates an example of a heat shield;
FIG. 4 illustrates an example of the heat shield formed from combination of heat shield
sections;
FIG. 5 illustration a section of the heat shield having an S-shaped cross section;
FIG. 6 illustration a section of the heat shield having an L-shaped cross section;
FIG. 7 illustrates a flow diagram of a method for assembling an apparatus that reduces
a turbine casing's exposure to heat.
DETAILED DESCRIPTION
[0009] A gap that is typically left between a blade track and a nozzle guide vane in a gas
turbine engine may be useful to decrease a risk that the blade track contacts the
nozzle guide vane during operating of the gas turbine engine. However, heat from hot
fluid flowing through blades that are located radially inward of the blade track may
pass radially outward through the gap and reach the turbine case.
[0010] By way of an introductory example, a system for reducing heat exposure of a turbine
casing in a gas turbine engine may be provided. The system includes a heat shield
positioned between a clip and an end of a blade track, a gap defined by an edge of
the heat shield and a nozzle guide vane, and a cavity defined by: the clip, the end
of the blade track, and the nozzle guide vane. The clip couples the blade track to
the turbine casing. The nozzle guide vane is coupled to the turbine casing. The heat
shield and the nozzle guide vane are positioned such that the gap closes and a seal
is formed in response to the heat shield and the nozzle guide vane thermally expanding
during operation of the gas turbine engine.
[0011] One interesting feature of the systems and methods described below may be that the
gap being sealed may reduce a temperature in the cavity during operation of the gas
turbine engine compared to the temperature in the cavity if the gap were not sealed.
Alternatively, or in addition, an interesting feature of the systems and methods described
below may be that the reduced temperatures in the cavity may increase a lifespan of
one or more components around the cavity, thus reducing replacement or maintenance
costs. Alternatively or in addition, an interesting feature of the systems and methods
described below may be that the materials typically used for relevant components may
be replaced by less expensive alternative materials as a result of the components
having reduced exposure to high temperatures.
[0012] FIG. 1 illustrates a cross-sectional view of a gas turbine engine 100 and a close-up
cross-sectional view of a portion of the gas turbine engine 100. The gas turbine engine
100 may be for propulsion of, for example, an aircraft. Alternatively or in addition,
the gas turbine engine 100 may be used to drive a propeller in aquatic applications,
or to drive a generator in energy applications. The gas turbine engine 100 may include
an intake section 120, a compressor section 160, a combustion section 130, a turbine
section 110, and an exhaust section 150. During operation of the gas turbine engine
100, fluid received from the intake section 120, such as air, travels along the axial
direction D1 and may be compressed within the compressor section 160. The compressed
fluid may then be mixed with fuel and the mixture may be burned in the combustion
section 130. The axial direction D1 may be the direction of fluid flow during operation
of the gas turbine engine 100. The combustion section 130 may include any suitable
fuel injection and combustion mechanisms. The hot, high pressure fluid may then pass
through the turbine section 110 to extract energy from the fluid and cause a turbine
shaft of a turbine 114 in the turbine section 110 to rotate, which in turn drives
the compressor section 160. Discharge fluid may exit the exhaust section 150.
[0013] As noted above, the hot, high pressure fluid may pass through the turbine section
110 during operation of the gas turbine engine 100. As the fluid flows through the
turbine section 110, the fluid may pass through a blade assembly 115, specifically
between adjacent blades 112 included in the blade assembly 115, coupled to the turbine
114 causing the turbine 114 to rotate. The rotating turbine 114 may turn a shaft 140
in a first rotational direction D2, for example. The blades 112 may rotate around
an axis of rotation, which may correspond to a centerline X of the turbine 114 in
some examples. The blade assembly 115 may include, for example, an arrangement of
the blades 112 in the turbine section 110 of the gas turbine engine 100.
[0014] As the hot, high pressure fluid passes through the turbine section 110, heat from
the fluid is transferred to components of the turbine section 110. Examples of components
that receive heat from the hot, high pressure fluid may include a nozzle guide vane
178 and a heat shield 170.
[0015] The nozzle guide vane 178 may be a component of the turbine section 110 that directs
the flow of the hot, high pressure fluid that passes through the turbine section 110
to, for example, a rotor. The nozzle guide vane 178 and an edge 176 of the heat shield
170 define a gap 180. The nozzle guide vane 178 may be a component configured to operate
in a nozzle guide vane cold state and, alternatively, in a nozzle guide vane hot state.
The nozzle guide vane cold state may be the state of operation of the nozzle guide
vane 178 in which the thermal expansion of the nozzle guide vane 178 is insufficient
to result in the gap 180 being sealed. Alternatively or in addition, the nozzle guide
vane 178 operating in the nozzle guide vane cold state may result in a fluid in a
fluid flow channel 184 accessing a cavity 182 via the gap 180.
[0016] Alternatively, the nozzle guide vane hot state may be the state of operation of the
nozzle guide vane 178 in which the thermal expansion of the nozzle guide vane 178
is sufficient to result in the gap 180 being sealed. Alternatively or in addition,
the nozzle guide vane 178 operating in the nozzle guide vane hot state may result
in the fluid in the turbine section 110 being inhibited from accessing the cavity
182 via the gap 180 for at least the reason that the gap 180 may be sealed.
[0017] The nozzle guide vane 178 is coupled to a turbine casing 188, and configured to thermally
expand in response to receiving heat from a first heat source. Examples of the first
heat source may be the fluid in the turbine section 110, a heating apparatus supplying
heat to the nozzle guide vane 178 such as a combustor, heat generated from friction
of moving parts in the gas turbine engine 100, or combinations thereof. For example,
the hot fluid travelling through the turbine section 110 during operation of the gas
turbine engine 100 may supply sufficient heat to the nozzle guide vane 178 resulting
in the nozzle guide vane 178 thermally expanding to contact the edge 176 of the heat
shield 170 resulting in the gap 180 being sealed. Alternatively or in addition, the
nozzle guide vane 178 may be a component that may couple with the heat shield 170
as a result of a thermal expansion of the nozzle guide vane 178, a thermal expansion
of the heat shield 170, or both. The nozzle guide vane 178 may include any material
capable of thermally expanding to couple with the heat shield 170. Examples of suitable
materials include nickel alloys such as Hastalloy X material, Rene41, any suitable
nickel alloy, any material that may resist hot gas temperatures, or combinations thereof.
In some examples, the nozzle guide vane 178 may include wear resistant material.
[0018] The heat shield 170 may be a component configured to operate in a heat shield cold
state and, alternatively, in a heat shield hot state. The heat shield cold state may
be the state of operation of the heat shield 170 in which the thermal expansion of
the heat shield 170 is insufficient to result in the gap 180 being sealed. Alternatively
or in addition, the heat shield 170 operating in the heat shield cold state may result
in the fluid in the fluid flow channel 184 accessing the cavity 182 via the gap 180.
[0019] Alternatively, the heat shield hot state may be the state of operation of the heat
shield 170 in which the thermal expansion of the heat shield 170 is sufficient to
result in the gap 180 being sealed. Alternatively or in addition, the heat shield
170 operating in the heat shield hot state may result in the fluid in the turbine
section 110 unable to access the cavity 182 via the gap 180 for at least the reason
that the gap 180 may be sealed. The heat shield 170 may be a component configured
to thermally expand in response to receiving heat from a second heat source. The second
heat source may be the same or different from the first heat source described above.
Examples of the second heat source may be the fluid in the turbine section 110, a
heating apparatus supplying heat to the nozzle guide vane 178, heat generated from
friction of moving parts in the gas turbine engine 100, or combinations thereof. For
example, the hot fluid travelling through the turbine section 110 during operation
of the gas turbine engine 100 may supply sufficient heat to the heat shield 170 resulting
in the heat shield 170 thermally expanding and as a result, the edge 176 of the heat
shield 170 may to contact the nozzle guide vane 178 and seal the gap 180. Alternatively
or in addition, the heat shield 170 may be a component that may couple with a nozzle
guide vane 178 as a result of the thermal expansion of the heat shield 170, the thermal
expansion of the nozzle guide vane 178, or both. Alternatively or in addition, the
heat shield 170 may be a component positioned between a clip 172 and an end 186 of
a blade track 174. The heat shield 170 may include any material capable of thermally
expanding to couple with the nozzle guide vane 178. Examples of suitable materials
include nickel alloys such as Hastalloy® X material, Rene41®, any suitable nickel
alloy, or combinations thereof.
[0020] The heat shield 170 and nozzle guide vane 178 may be present in any section of the
gas turbine engine 100. For example, the heat shield 170 and the nozzle guide vane
178 may be present in the turbine section 110, as shown in FIG. 1. Alternatively or
in addition, the heat shield 170 and the nozzle guide vane 178 may be present in the
intake section 120, the combustion section 130, the exhaust section 150, the compressor
section 160, or combinations thereof.
[0021] The gap 180 is an opening between the edge 176 of the heat shield 170 and the nozzle
guide vane 178. The gap 180 includes a distance between the heat shield 170 and the
nozzle guide vane 178 such that the thermal expansion of the heat shield 170 and the
nozzle guide vane 178 may result in the gap 180 being sealed or closed. Alternatively
or in addition, the gap 180 may be a channel that facilitates mass transfer between
the cavity 182 and the fluid flow channel 184. Alternatively or in addition, mass
transfer between the cavity 182 and the fluid flow channel 184 may be suspended as
a result of the gap 180 being sealed.
[0022] The blade track 174 may include a track that guides blades 112 as the blades 112
rotate within the turbine 114. The blade track 174 may include an indentation or recess
that allows insertion of a tip of the blade 112. Thus inserted, the tip of the blade
112 may limit or block fluid in the fluid flow channel 184 from travelling over the
tip of the blade 112. Alternatively or in addition, as a result of the blade tip inserted
into the blade track 174, fluid in the fluid flow channel 184 may be directed to flow
around a portion of the blade 112 that results in the blade 112 rotating around the
turbine 114. Alternatively or in addition, the end 186 of the blade track 174 may
partially shape of the clip 172 may be any suitable shape such that the heat shield
170 may be positioned between the clip 172 and the end 186 of the blade track 174.
In some examples, the clip 172 may have a C-shape, as shown in FIG. 1 and FIG. 2.
In some examples, the clip 172 may be brazed or welded to the turbine casing 188.
Alternatively or in addition, the clip 172 may include a hook 290 that may couple
the clip 172 and the turbine casing 188. Alternatively or in addition, the clip 172
may inhibit the heat shield 170 from rotating in a second rotational direction D3.
The clip 172 may be made from various materials. Examples of suitable materials include
nickel alloys such as Hastalloy® X material, Rene41®, any suitable nickel alloy, or
combinations thereof. Alternatively or in addition, the clip 172 may include a plurality
of clip slots 214. The clip slots 214 may be slots in the clip 172 sized to receive
an anti-rotation pin 210. In some examples, the clip 172 may have clip slots 214 located
at a first clip end 230 and a second clip end 240 of the clip 172, as shown in FIG.
2. The clip slots 214 may be sized such that the anti-rotation pin 210 may penetrate
the clip 172 at the first clip end 230 and emerge from the second clip end 240.
[0023] The second rotational direction D3 may be a rotational direction orthogonal to the
first rotational direction D2. Additionally, the second rotational direction D3 may
be a rotational direction parallel to the plane depicting the cross section of the
portion of the gas turbine engine 100 shown in FIG. 2.
[0024] The hook 290 may be a component of the clip 172 that couples the clip 172 to the
turbine casing 188. Alternatively or in addition, the hook 290 may be a claw or tooth
of the clip 172 that may couple the clip 172 with the turbine casing 188. In some
examples, the hook 290 may be brazed or welded to the turbine casing 188. In some
examples, the hook 290 may be removeably attached to the turbine casing 188. In some
examples, the clip 172 may be inhibited from moving as a result of the hook 290 coupled
to the turbine casing 188.
[0025] FIG. 2 shows the anti-rotation pin 210 inserted in the first clip slot 230 and the
second clip slot 240 as well as contacting the heat shield 170. The anti-rotation
pin 210 may be a bar or shaft that inhibits rotation of the heat shield 170 in the
first rotational direction D2. As mentioned above, the first rotational direction
D2 may be the direction of rotation of the blades 112 during operation of the gas
turbine engine 100. In some examples, the anti-rotation pin 210 may be inserted into
a heat shield shape of the clip 172 may be any suitable shape such that the heat shield
170 may be positioned between the clip 172 and the end 186 of the blade track 174.
In some examples, the clip 172 may have a C-shape, as shown in FIG. 1 and FIG. 2.
In some examples, the clip 172 may be brazed or welded to the turbine casing 188.
Alternatively or in addition, the clip 172 may include a hook 290 that may couple
the clip 172 and the turbine casing 188. Alternatively or in addition, the clip 172
may inhibit the heat shield 170 from rotating in a second rotational direction D3.
The clip 172 may be made from various materials. Examples of suitable materials include
nickel alloys such as Hastalloy X material, Rene41, any suitable nickel alloy, or
combinations thereof. Alternatively or in addition, the clip 172 may include a plurality
of clip slots 214. The clip slots 214 may be slots in the clip 172 sized to receive
an anti-rotation pin 210. In some examples, the clip 172 may have clip slots 214 located
at a first clip end 230 and a second clip end 240 of the clip 172, as shown in FIG.
2. The clip slots 214 may be sized such that the anti-rotation pin 210 may penetrate
the clip 172 at the first clip end 230 and emerge from the second clip end 240.
[0026] The second rotational direction D3 may be a rotational direction orthogonal to the
first rotational direction D2. Additionally, the second rotational direction D3 may
be a rotational direction parallel to the plane depicting the cross section of the
portion of the gas turbine engine 100 shown in FIG. 2.
[0027] The hook 290 may be a component of the clip 172 that couples the clip 172 to the
turbine casing 188. Alternatively or in addition, the hook 290 may be a claw or tooth
of the clip 172 that may couple the clip 172 with the turbine casing 188. In some
examples, the hook 290 may be brazed or welded to the turbine casing 188. In some
examples, the hook 290 may be removeably attached to the turbine casing 188. In some
examples, the clip 172 may be inhibited from moving as a result of the hook 290 coupled
to the turbine casing 188.
[0028] FIG. 2 shows the anti-rotation pin 210 inserted in the first clip slot 230 and the
second clip slot 240 as well as contacting the heat shield 170. The anti-rotation
pin 210 may be a bar or shaft that inhibits rotation of the heat shield 170 in the
first rotational direction D2. As mentioned above, the first rotational direction
D2 may be the direction of rotation of the blades 112 during operation of the gas
turbine engine 100. The anti-rotation pin 210 is inserted into a heat shield slot
310 (shown in FIG. 3). In addition, the anti-rotation pin 210 may assert pressure
onto a surface 218 of the heat shield 170. In some examples, the pressure asserted
onto the surface 218 of the heat shield 170 by the anti-rotation pin 210 may inhibit
the heat shield 170 from moving in any direction. Alternatively, in some examples,
the pressure asserted onto the surface 218 of the heat shield 170 may inhibit rotation
of the heat shield 170 in the first rotational direction D2. The heat shield slot
310 is explained in more detail below.
[0029] The heat shield 170 may include a side-view cross section T. The side-view cross
section T may be a surface or shape that is or would be exposed by making a straight
cut through the heat shield 170 in the axial direction D1 when the heat shield 170
is installed in the gas turbine engine 100. Alternatively or in addition, a plane
of the side-view cross section T may be any plane that includes the centerline X when
the heat shield 170 is installed in the gas turbine engine 100. The side-view cross
section T may be S-shaped, L-shaped, or any suitable shape such that the heat shield
170 may be positioned and maintained between the end 186 of the blade track 174 and
the clip 172. Alternatively or in addition, the heat shield 170 may be any suitable
shape such that, as a result of the heat shield 170 operating in the heat shield hot
state and/or the nozzle guide vane 178 operating in the nozzle guide vane hot state,
the edge 176 of the heat shield 170 contacts the nozzle guide vane 178, thus sealing
the gap 180.
[0030] A conduit 222 may be defined by a space between the clip 172 and a portion of the
nozzle guide vane 178. The conduit 222 may connect the cavity 182 and a recess 224.
The conduit 222 may be a straight or curved passage. The recess 224 may be a space
defined by the clip 172, the turbine casing 188, and a portion of the nozzle guide
vane 178.
[0031] A W-seal 220 may be included in the recess 224. The W-seal 220 may be a structure
that inhibits hot fluid from the fluid flow channel 184 from contacting the turbine
casing 188. Hot fluid from the fluid flow channel 184 may unintentionally leak through
the heat shield 170 or the nozzle guide vane 178 or otherwise travel through the heat
shield 170 and nozzle guide vane 178 despite the heat shield 170 operating in the
heat shield hot state, despite the nozzle guide vane 178 operating in the nozzle guide
vane hot state, or despite both. The W-seal 220 may be a greater distance from the
gap 180 than the heat shield's 170 distance from the gap 180. Alternatively or in
addition, hot fluid from the fluid flow channel 184 may enter the recess 224 in response
to the gap 180 being open.
[0032] For example, as a result of the gap 180 being open, fluid from the fluid flow channel
184 may travel from the fluid flow channel 184, radially outward through the gap 180
into the cavity 182. From the cavity 182, the fluid may travel through the conduit
222 into the recess 224. The W-seal 220 may, for example, inhibit fluid that has reached
the recess 224 from contacting the turbine casing 188.
[0033] FIG. 3 shows an example of the heat shield 170. The heat shield 170 shown in FIG.
3 includes the heat shield slot 310. As mentioned above, the heat shield 170 includes
the heat shield slot 310. The heat shield slot 310 is an opening sized to receive
the anti-rotation pin 210. The heat shield 170 is inhibited from rotating in the first
rotational direction D2 as a result of the anti-rotation pin 210 having been received
in the heat shield slot 310. In addition, the heat shield 170 may be inhibited from
rotating in the first rotational direction D2 as a result of the anti-rotation pin
210 applying pressure onto the surface 218 of the heat shield 170. Examples of the
heat shield slot 310 may include an indentation or an opening sized to receive the
anti-rotation pin 210. In the example shown in FIG. 3, the heat shield 170 includes
the single heat shield slot 310. In some examples, the heat shield may include multiple
heat shield slots.
[0034] The heat shield 170 may include an upper lip 330, a middle portion 320, and a lower
lip 340. The upper lip 330 may be a portion of the heat shield 170 that extends at
an angle from the surface 218 of the heat shield 170. The upper lip 330 may contact
the clip 172 as a result of the heat shield 170 positioned between the end 186 of
the blade track 174 and the clip 172.
[0035] The middle portion 320 may include the surface 218. The middle portion may be the
portion of the heat shield 170 that connects the upper lip 330 and the lower lip 340.
The middle portion may be parallel with a plane A. Alternatively, the middle portion
320 may be non-planar.
[0036] The lower lip 340 may be a portion of the heat shield 170 that extends at an angle
from the surface 218 of the heat shield 170. The lower lip may contact the end 186
of the blade track 174 in response to the heat shield positioned between the clip
172 and the end 186 of the blade track 174. Alternatively or in addition, the lower
lip 340 may include the edge 186 of the heat shield 170. As mentioned above, the edge
186 of the heat shield 170 may contact the nozzle guide vane 178 as a result of the
gap 180 being sealed, as a result of the nozzle guide vane 178 operating in the nozzle
guide vane hot state, or as a result of the heat shield 170 operating in the heat
shield hot state.
[0037] The upper lip 330, the middle portion 320, and the lower lip 340 may all be annularly
shaped around the centerline X. Alternatively or in addition, in some examples, the
heat shield 170 may have an annular cross section in a plane perpendicular to the
centerline X. The upper lip 330, the middle portion 320, and the lower lip 340 may
be independently shaped. The upper lip 330, the middle portion 320, and the lower
lip 340 may each be annular, rectangular, or any suitable shape such that the heat
shield 170 may be positioned and maintained between the end 186 of the blade track
174 and the clip 172.
[0038] FIG. 4 shows an example of the heat shield 170. The heat shield 170 shown in FIG.
4 includes a plurality of sections 410 of the heat shield 170 coupled together, for
example by brazing or welding. The sections 410 may be fixedly or removably coupled
together. Alternatively or in addition, the coupling of the sections 410 may occur
at a plurality of interfaces 420. The interfaces 420 may be the portions of sections
410 that contact adjacent sections 410. The sections 410 may include the heat shield
slot 310. The sections 410 may be combined to form the heat shield 170 such that the
heat shield 170 fits between the clip 172 and the end 186 of the blade track 174.
[0039] FIG. 5 shows an example of a portion of the heat shield 170. The portion of the heat
shield 170 shown in FIG. 5 shows the side-view cross section T of the heat shield
170 formed in an S-shape. The side-view cross section T may be the cross section of
the heat shield 170 that is formed by a combination of cross sections of the upper
lip 330, the middle portion 320 and the lower lip 340. The side-view cross section
T of the heat shield 170 may be any suitable shape such that the heat shield 170 may
fit between the clip 172 and the end 186 of the blade track 174.
[0040] FIG. 6 shows an example of a portion of another example of the heat shield 170. The
portion of the heat shield 170 shown in FIG. 6 shows the side-view cross section T
of the heat shield 170 formed in an L-shape. Alternatively, in some examples, the
side-view cross section T may be formed in a J-shape. In some examples, the side view
cross section T of the heat shield 170 includes the combination of cross sections
of the lower lip 340 and the middle portion 320.
[0041] FIG. 7 shows a flowchart for a method of assembling cooling components of the gas
turbine engine 100. The method includes coupling 802 the blade track 174 to the casing
188. In some examples the coupling 802 of the blade track 174 to the casing 188 includes
inserting the anti-rotation pin 210 to assist in coupling the blade track 174 and
the casing 188. The method includes positioning 804 the heat shield 170 on the blade
track 174. In some examples, the heat shield 170 is positioned to encounter the anti-rotation
pin 210 and the anti-rotation pin 210 is inserted into the heat shield slot 310. The
method includes coupling 806 the clip 172 to the blade track 174. Alternatively or
in addition, the clip 172 may be coupled to the casing 188. The clip 172 is positioned
such that the heat shield 170 is between the clip 172 and the blade track 174. The
method includes installing 808 the nozzle guide vane 174 leaving the gap 180. The
gap 180 is defined by the edge 176 of the heat shield 170 and the nozzle guide vane
178. The edge 176 of the heat shield 170 are configured such as to form a seal and
close the gap 180 in response to a thermal expansion of the heat shield 170 and the
thermal expansion of the nozzle guide vane 178. The gap 180 being sealed inhibits
hot fluid from contacting the casing 188. In some examples, the clip 172 may hold
the heat shield 170 in place. The positioning of the heat shield 170 may be such that
the gap 180 is sealed as a result of the heat shield operating in the heat shield
hot state, the nozzle guide vane 178 operating in the nozzle guide vane 178 hot state,
or a combination thereof. Alternatively or in addition, the gap 180 being sealed may
prevent fluid, for example from the fluid flow channel 184 from entering the cavity
182 and contacting the turbine casing 188 or otherwise contacting the turbine casing
188.
[0042] Alternatively or in addition, the method may include welding, brazing, or some combination
thereof, the heat shield 170 to the blade track 174. The welding, brazing or combination
thereof may occur before or after the other steps of assembly of the cooling components,
or even pre-assembled. Alternatively or in addition, the method may include welding,
brazing, some combination thereof, the heat shield 170 to the end 186 of the blade
track 174. The method includes inserting the anti-rotation pin 210 into the heat shield
slot 310. In addition, the method may include applying pressure with the anti-rotation
pin 310 onto the surface 218 of the heat shield 170. Alternatively or in addition,
the method may include coupling the clip 172 to the turbine casing 188 by the hook
290. Alternatively or in addition, the method may include assembling the heat shield
from the plurality of sections 410.
[0043] To clarify the use of and to hereby provide notice to the public, the phrases "at
least one of <A>, <B>, ... and <N>" or "at least one of <A>, <B>, ... <N>, or combinations
thereof" or "<A>, <B>, ... and/or <N>" are defined by the Applicant in the broadest
sense, superseding any other implied definitions hereinbefore or hereinafter unless
expressly asserted by the Applicant to the contrary, to mean one or more elements
selected from the group comprising A, B, ... and N. In other words, the phrases mean
any combination of one or more of the elements A, B, ... or N including any one element
alone or the one element in combination with one or more of the other elements which
may also include, in combination, additional elements not listed.
[0044] While various embodiments have been described, it will be apparent to those of ordinary
skill in the art that many more embodiments and implementations are possible. Accordingly,
the embodiments described herein are examples, not the only possible embodiments and
implementations. The invention is defined only by the appended claims.
1. A system for a gas turbine engine, the system comprising:
a turbine casing (188);
a clip (172);
an anti-rotation pin (210);
a blade track (174) coupled to the turbine casing (188) with the clip (172);
a nozzle guide vane (178) coupled to the turbine casing (188), wherein an end of the
blade track (174), the clip (172), and a portion of the nozzle guide vane (178) form
a cavity (182); and
a heat shield (170) positioned between the clip (172) and the end of the blade track
(174) in the cavity (182), an edge (176) of the heat shield (170) and the portion
of the nozzle guide vane (178) form a gap (180),
characterized in that
the heat shield (170) and the nozzle guide vane (178) are configured to close the
gap (180) in response to a thermal expansion of the heat shield (170) and a thermal
expansion of the nozzle guide vane (178),
wherein the heat shield (170) comprises a slot (310) to receive the anti-rotation
pin (210), wherein the clip (172) is coupled to the anti-rotation pin (210) at a first
end (230) of the clip (172) and at a second end (240) of the clip (172), the first
end (230) of the clip (172) opposite the second end (240) of the clip (172).
2. The system of claim 1, wherein the heat shield (170) is inhibited from rotating in
a first rotational direction by the anti-rotation pin (210), the first rotational
direction being a direction of rotation of a turbine blade assembly housed within
the turbine casing, and the heat shield is inhibited from rotating in a second rotational
direction by the clip, the second rotational direction orthogonal to the first rotational
direction.
3. The system of any of claims 1 to 2, wherein the heat shield (170) comprises a plurality
of segments (410) fixedly coupled together.
4. The system of any of claims 1 to 3, wherein the clip (172) has a C-shape.
5. The system of any of claims 1 to 4, wherein the heat shield (170) has a cross section
defined by an intersection of the heat shield and a plane including the axis of rotation
of a turbine blade assembly, the turbine blade assembly housed in the turbine casing,
and the cross section having an S-shape or an L-shape.
6. The system of any of claims 1 to 5, wherein the heat shield (170) has a cross section,
the cross section defined by a plane perpendicular to the axis of rotation of a turbine
blade assembly, the turbine blade assembly housed in the turbine casing, the cross
section having an annular shape.
7. The system of any of claims 1 to 6, wherein the heat shield (170) is welded or brazed
to the blade track.
8. The system of any of claims 1 to 7, further comprising a W-seal (220), the W-seal
(220) positioned a first distance radially outward from an axis of rotation of a turbine
blade assembly and the heat shield positioned a second distance radially outward from
the axis of rotation of the turbine blade assembly the first distance being greater
than the second distance.
9. The system of claim 4, wherein
the heat shield (170) is in a shape of an "S", the heat shield (170) having a first
edge on one end of the "S" and a second edge on the other end of the "S", the first
edge of the heat shield (170) located between the C-shaped clip (172) and the end
of the blade track (174), the second edge of the heat shield (170) and the nozzle
guide vane (178) form the gap (180), the heat shield (170) and the nozzle guide (178)
vane configured to close the gap (180) in response to a thermal expansion of the heat
shield (170) and a thermal expansion of the nozzle guide vane (178); the system further
comprising:
a pin (210) configured to inhibit the heat shield from rotating in a first rotational
direction, the heat shield comprising a slot configured to receive the pin, the pin
positioned in the slot; and
the C-shaped clip (172) configured to inhibit the S-shaped heat shield from rotating
in a second rotational direction that is orthogonal to the first rotational direction.
10. A method for assembling a system for a gas turbine engine, the method comprising:
coupling a blade track (174) to a turbine casing (188);
positioning a heat shield (170) on the blade track;
coupling a clip (172) and the blade track, the heat shield positioned between the
clip and the blade track;
inserting an anti-rotation pin (210) in a first clip slot (230) and a second clip
slot (240), the first clip slot and the second clip slot located at a first clip end
and a second clip end, respectively, the first end of the clip being opposite the
second end of the clip;
inserting the anti-rotation pin into a slot (310) of the heat shield, the slot configured
to receive the anti-rotation pin; and
installing a nozzle guide vane leaving a gap (180) defined by an edge (176) of the
heat shield and the nozzle guide vane, the edge and the nozzle guide vane being configured
such as to form a seal and close the gap in response to a thermal expansion of the
heat shield and a thermal expansion of the nozzle guide vane, the seal configured
to prevent a fluid flow through the gap to the turbine casing.
11. The method of claim 10 further comprising welding the heat shield to the blade track.
1. System für einen Gasturbinenmotor, wobei das System Folgendes aufweist:
ein Turbinengehäuse (188);
einen Clip (172);
einen Drehschutzstift (210);
eine Schaufelbahn (174), die über den Clip (172) mit dem Turbinengehäuse (188) verbunden
ist;
eine Düsenführungsschaufel (178), die mit dem Turbinengehäuse (188) verbunden ist,
wobei ein Ende der Schaufelbahn (174), der Clip (172) und ein Teil der Düsenführungsschaufel
(178) einen Hohlraum (182) bilden und;
einen Hitzeschild (170), der zwischen dem Clip (172) und dem Ende der Schaufelbahn
(174) in dem Hohlraum (182) positioniert ist, wobei eine Kante (176) des Hitzeschilds
(170) und der Teil der Düsenführungsschaufel (178) einen Spalt (180) bilden,
dadurch gekennzeichnet, dass
der Hitzeschild (170) und die Düsenführungsschaufel (178) ausgebildet sind, den Spalt
(180) in Reaktion auf eine Wärmeausdehnung des Hitzeschilds (170) und eine Wärmeausdehnung
der Düsenführungsschaufel (178) zu schließen,
wobei der Hitzeschild (170) einen Schlitz (310) zum Aufnehmen des Drehschutzstifts
(210) aufweist, wobei der Clip (172) an einem ersten Ende (230) des Clips (172) und
an einem zweiten Ende (240) des Clips (172) mit dem Drehschutzstift (210) verbunden
ist, wobei das erste Ende (230) des Clips (172) dem zweiten Ende (240) des Clips (172)
gegenüberliegt.
2. System nach Anspruch 1, wobei der Hitzeschild (170) durch den Drehschutzstift (210)
an einem Drehen in einer ersten Drehrichtung gehindert wird, wobei die erste Drehrichtung
eine Drehrichtung einer Turbinenschaufelbaugruppe ist, die sich in dem Turbinengehäuse
befindet, und der Hitzeschild durch den Clip an einem Drehen in einer zweiten Drehrichtung
gehindert wird, wobei sich die zweite Drehrichtung orthogonal zur ersten Drehrichtung
befindet.
3. System nach einem der Ansprüche 1 bis 2, wobei der Hitzeschild (170) aus einer Vielzahl
von fest miteinander verbundenen Segmenten (410) besteht.
4. System nach einem der Ansprüche 1 bis 3, wobei der Clip (172) eine C-Form aufweist.
5. System nach einem der Ansprüche 1 bis 4, wobei der Hitzeschild (170) einen Querschnitt
aufweist, der durch einen Schnittpunkt des Hitzeschilds und einer Ebene, die die Drehachse
einer Turbinenschaufelbaugruppe beinhaltet, definiert wird, wobei sich die Turbinenschaufelbaugruppe
in dem Turbinengehäuse befindet und der Querschnitt eine S-Form oder eine L-Form hat.
6. System nach einem der Ansprüche 1 bis 5, wobei der Hitzeschild (170) einen Querschnitt
aufweist, der durch eine Ebene definiert wird, die sich senkrecht zur Drehachse einer
Turbinenschaufelbaugruppe befindet, wobei sich die Turbinenschaufelbaugruppe in dem
Turbinengehäuse befindet und der Querschnitt eine ringförmige Form hat.
7. System nach einem der Ansprüche 1 bis 6, wobei der Hitzeschild (170) an die Schaufelbahn
geschweißt oder gelötet ist.
8. System nach einem der Ansprüche 1 bis 7, das darüber hinaus eine W-Dichtung (220)
aufweist, wobei die W-Dichtung (220) in einem ersten Abstand radial nach außen von
einer Drehachse einer Turbinenschaufelbaugruppe positioniert ist und der Hitzeschild
in einem zweiten Abstand radial nach außen von der Drehachse der Turbinenschaufelbaugruppe
positioniert ist, wobei der erste Abstand größer als der zweite Abstand ist.
9. System nach Anspruch 4, wobei der Hitzeschild (170) die Form eines "S" hat, wobei
der Hitzeschild (170) eine erste Kante an einem Ende des "S" und eine zweite Kante
an dem anderen Ende des "S" hat, wobei sich die erste Kante des Hitzeschilds (170)
zwischen dem C-förmigen Clip (172) und dem Ende der Schaufelbahn (174) befindet, die
zweite Kante des Hitzeschilds (170) und die Düsenführungsschaufel (178) den Spalt
(180) bilden, der Hitzeschild (170) und die Düsenführungsschaufel (178) ausgebildet
sind, den Spalt (180) in Reaktion auf eine Wärmeausdehnung des Hitzeschilds (170)
und eine Wärmeausdehnung der Düsenführungsschaufel (178) zu schließen; wobei das System
darüber hinaus Folgendes aufweist:
einen Stift (210), der ausgebildet ist, um den Hitzeschild an einem Drehen in einer
ersten Drehrichtung zu hindern, wobei der Hitzeschild einen Schlitz aufweist, der
ausgebildet ist zum Aufnehmen des Stifts, wobei der Stift in dem Schlitz positioniert
ist; und
den C-förmigen Clip (172), der ausgebildet ist, um den S-förmigen Hitzeschild an einem
Drehen in einer zweiten Drehrichtung zu hindern, die sich orthogonal zur ersten Drehrichtung
befindet.
10. Verfahren zum Zusammenbauen eines Systems für einen Gasturbinenmotor, wobei das Verfahren
Folgendes aufweist:
Verbinden einer Schaufelbahn (174) mit einem Turbinengehäuse (188);
Positionieren eines Hitzeschilds (170) auf der Schaufelbahn;
Verbinden eines Clips (172) und der Schaufelbahn, wobei der Hitzeschild zwischen dem
Clip und der Schaufelbahn positioniert ist;
Einsetzen eines Drehschutzstifts (210) in einen ersten Clip-Schlitz (230) und einen
zweiten Clip-Schlitz (240), wobei sich der erste Clip-Schlitz und der zweite Clip-Schlitz
an einem ersten Clip-Ende bzw. an einem zweiten Clip-Ende befinden und das erste Ende
des Clips dem zweiten Ende des Clips gegenüberliegt;
Einsetzen des Drehschutzstifts in einen Schlitz (310) des Hitzeschilds, wobei der
Schlitz ausgebildet ist zum Aufnehmen des Drehschutzstifts; und
Installieren einer Düsenführungsschaufel, die einen Spalt (180) belässt, der durch
eine Kante (176) des Hitzeschilds und die Düsenführungsschaufel definiert wird, wobei
die Kante und die Düsenführungsschaufel so ausgebildet sind, dass sie eine Dichtung
bilden und den Spalt in Reaktion auf eine Wärmeausdehnung des Hitzeschilds und eine
Wärmeausdehnung der Düsenführungsschaufel schließen, wobei die Dichtung ausgebildet
ist zum Verhindern, dass ein Fluid durch den Spalt in das Turbinengehäuse strömen
kann.
11. Verfahren nach Anspruch 10, das darüber hinaus das Schweißen des Hitzeschilds auf
die Schaufelbahn aufweist.
1. Système pour turboréacteur, le système comprenant :
un carter de turbine (188) ;
une attache (172) ;
une goupille anti-rotation (210) ;
une piste d'aube (174) accouplée au carter de turbine (188) avec l'attache (172) ;
une aube de distributeur de turbine (178) accouplée au carter de turbine (188), une
extrémité de la piste d'aube (174), l'attache (172) et une partie de l'aube de distributeur
de turbine (178) formant une cavité (182) ; et
un bouclier thermique (170) positionné entre l'attache (172) et l'extrémité de la
piste d'aube (174) dans la cavité (182), un bord (176) du bouclier thermique (170)
et la partie de l'aube de distributeur de turbine (178) formant un espace (180),
caractérisé en ce que
le bouclier thermique (170) et l'aube de distributeur de turbine (178) sont conçus
pour fermer l'espace (180) en réponse à une dilatation thermique du bouclier thermique
(170) et à une dilatation thermique de l'aube de distributeur de turbine (178),
le bouclier thermique (170) comprenant une fente (310) pour recevoir la goupille anti-rotation
(210), l'attache (172) étant accouplée à la goupille anti-rotation (210) au niveau
d'une première extrémité (230) de l'attache (172) et au niveau d'une seconde extrémité
(240) de l'attache (172), la première extrémité (230) de l'attache (172) étant opposée
à la seconde extrémité (240) de l'attache (172).
2. Système selon la revendication 1, le bouclier thermique (170) étant empêché de tourner
dans un premier sens de rotation par la goupille anti-rotation (210), le premier sens
de rotation étant un sens de rotation d'un ensemble d'aubes de turbine logé dans le
carter de turbine, et le bouclier thermique étant empêché de tourner dans un second
sens de rotation par l'attache, le second sens de rotation étant orthogonal au premier
sens de rotation.
3. Système selon l'une quelconque des revendications 1 et 2, le bouclier thermique (170)
comprenant une pluralité de segments (410) accouplés de manière fixe entre eux.
4. Système selon l'une quelconque des revendications 1 à 3, l'attache (172) ayant une
forme en C.
5. Système selon l'une quelconque des revendications 1 à 4, le bouclier thermique (170)
ayant une section transversale définie par une intersection du bouclier thermique
et un plan comprenant l'axe de rotation d'un ensemble d'aubes de turbine, l'ensemble
d'aubes de turbine étant logé dans le carter de turbine, et la section transversale
ayant une forme en S ou en L.
6. Système selon l'une quelconque des revendications 1 à 5, le bouclier thermique (170)
ayant une section transversale, la section transversale étant définie par un plan
perpendiculaire à l'axe de rotation d'un ensemble d'aubes de turbine, l'ensemble d'aubes
de turbine étant logé dans le carter de turbine, la section transversale ayant une
forme annulaire.
7. Système selon l'une quelconque des revendications 1 à 6, le bouclier thermique (170)
étant soudé ou brasé sur la piste d'aube.
8. Système selon l'une quelconque des revendications 1 à 7, comprenant en outre un joint
en W (220), le joint en W (220) étant positionné à une première distance radialement
vers l'extérieur d'un axe de rotation d'un ensemble d'aubes de turbine et le bouclier
thermique étant positionné à une seconde distance radialement vers l'extérieur de
l'axe de rotation de l'ensemble d'aubes de turbine, la première distance étant supérieure
à la seconde distance.
9. Système selon la revendication 4,
le bouclier thermique (170) étant en forme de « S », le bouclier thermique (170) ayant
un premier bord à une extrémité du « S » et un second bord à l'autre extrémité du
« S », le premier bord du bouclier thermique (170) étant situé entre l'attache en
forme de C (172) et l'extrémité de la piste d'aube (174), le second bord du bouclier
thermique (170) et l'aube de distributeur de turbine (178) formant l'espace (180),
le bouclier thermique (170) et l'aube de distributeur de turbine (178) étant conçus
pour fermer l'espace (180) en réponse à une dilatation thermique du bouclier thermique
(170) et à une dilatation thermique de l'aube de distributeur de turbine (178) ; le
système comprenant en outre :
une goupille (210) conçue pour empêcher le bouclier thermique de tourner dans un premier
sens de rotation, le bouclier thermique comprenant une fente conçue pour recevoir
la goupille, la goupille étant positionnée dans la fente ; et
l'attache en forme de C (172) conçue pour empêcher le bouclier thermique en forme
de S de tourner dans un second sens de rotation qui est perpendiculaire au premier
sens de rotation.
10. Procédé d'assemblage d'un système pour turboréacteur, le procédé comprenant les étapes
consistant à :
accoupler une piste d'aube (174) à un carter de turbine (188) ;
positionner un bouclier thermique (170) sur la piste d'aube ;
accoupler une attache (172) et la piste d'aube, le bouclier thermique étant positionné
entre l'attache et la piste d'aube ;
insérer une goupille anti-rotation (210) dans une première fente d'attache (230) et
une seconde fente d'attache (240), la première fente d'attache et la seconde fente
d'attache étant situées respectivement au niveau d'une première extrémité d'attache
et d'une seconde extrémité d'attache, la première extrémité de l'attache étant opposée
à la seconde extrémité de l'attache ;
insérer la goupille anti-rotation dans une fente (310) du bouclier thermique, la fente
étant conçue pour recevoir la goupille anti-rotation ; et
installer une aube de distributeur de turbine laissant un espace (180) défini par
un bord (176) du bouclier thermique et l'aube de distributeur de turbine, le bord
et l'aube de distributeur de turbine étant conçus de sorte à former un joint et à
fermer l'espace en réponse à une dilatation thermique du bouclier thermique et à une
dilatation thermique de l'aube de distributeur de turbine, le joint étant conçu pour
empêcher un écoulement de fluide à travers l'espace vers le carter de turbine.
11. Procédé selon la revendication 10 comprenant en outre l'étape consistant à souder
le bouclier thermique sur la piste d'aube.