U.S. patent application number 11/807390 was filed with the patent office on 2008-12-04 for turbine vane with divided turbine vane platform.
This patent application is currently assigned to Siemens Power Generation, Inc.. Invention is credited to Bonnie D. Marini.
Application Number | 20080298973 11/807390 |
Document ID | / |
Family ID | 40088440 |
Filed Date | 2008-12-04 |
United States Patent
Application |
20080298973 |
Kind Code |
A1 |
Marini; Bonnie D. |
December 4, 2008 |
Turbine vane with divided turbine vane platform
Abstract
A turbine vane with endwalls, wherein at least one endwall is
formed from two or more sections configured such that the sections
form releasable joints with a generally elongated airfoil of the
turbine vane. The sections may be configured to both support the
generally elongated airfoil and to establish cooling fluid
flowpaths between the sections and the generally elongated airfoil
to cool the aspects of the turbine vane proximate to the
intersection of the endwalls and the generally elongated airfoil.
In addition, the joints between the generally elongated airfoil and
the sections may be formed from a connection system that enables
forces to be transmitted from the generally elongated airfoil to
the endwalls without creating stresses found in conventional
turbine vane fillets at the intersection between the generally
elongated airfoil and the endwalls.
Inventors: |
Marini; Bonnie D.; (Oviedo,
FL) |
Correspondence
Address: |
Siemens Corporation;Intellectual Property Department
170 Wood Avenue South
Iselin
NJ
08830
US
|
Assignee: |
Siemens Power Generation,
Inc.
|
Family ID: |
40088440 |
Appl. No.: |
11/807390 |
Filed: |
May 29, 2007 |
Current U.S.
Class: |
416/223R |
Current CPC
Class: |
F05D 2260/36 20130101;
F05D 2240/80 20130101; F01D 5/147 20130101; F01D 9/02 20130101 |
Class at
Publication: |
416/223.R |
International
Class: |
F01D 5/14 20060101
F01D005/14 |
Claims
1. A turbine vane, comprising: a generally elongated airfoil formed
from an outer wall, and having a leading edge, a trailing edge, a
pressure side, and a suction side, a first endwall at a first end,
a second endwall at a second end opposite the first end; wherein
the first endwall is formed from at least first and second sections
positioned adjacent to each other and to the airfoil such that each
section forms a releasable joint with the generally elongated
airfoil; wherein the first section includes a hot gas path surface
generally orthogonal to the generally elongated airfoil, a cold
side surface opposite to the hot gas path surface, an upstream
edge, a downstream edge opposite to the upstream edge, and first
and second side edges opposite to each other, wherein the first
side edge of the first section is positioned in close proximity
with the generally elongated airfoil; wherein the first section
includes a first section attachment system on the first side edge
of the first section, the first section attachment system being
formed from at least one loading bearing surface for transferring
loads from the generally elongated airfoil to the first section so
that the first section supports and positions the turbine vane
within a turbine engine and including at least one cooling fluid
channel on the first side edge that is defined by the first side
edge of the first section and the outer surface of the generally
elongated airfoil to cool a region of the airfoil at an
intersection between the generally elongated airfoil and the first
section, wherein the at least one cooling fluid channel creates a
cooling fluid pathway for cooling fluids to flow between the first
section and the generally elongated airfoil.
2. The turbine vane of claim 1, wherein the second section includes
a hot gas path surface generally orthogonal to the generally
elongated airfoil, a cold side surface opposite to the hot gas path
surface, an upstream edge, a downstream edge opposite to the
upstream edge, and first and second side edges opposite to each
other, wherein the first side edge of the second section is
positioned in close proximity with the generally elongated airfoil.
wherein the second section includes a second section attachment
system on the first side edge of the second section, the second
section attachment system being formed from at least one loading
bearing surface for transferring loads from the generally elongated
airfoil to the second section so that the second section supports
and positions the turbine vane within a turbine engine and
including at least one cooling fluid channel on the first side edge
that is defined by the first side edge of the second section and
the outer surface of the generally elongated airfoil to cool a
region of the airfoil at an intersection between the generally
elongated airfoil and the second section, wherein the at least one
cooling fluid channel creates a cooling fluid pathway for cooling
fluids to flow between the second section and the generally
elongated airfoil.
3. The turbine vane of claim 2, wherein the at least one load
bearing surface of the first section attachment system is
positioned on a projection extending from the first side edge of
the first section that is received within a groove in the generally
elongated airfoil.
4. The turbine vane of claim 3, wherein the projection extends
along the first side edge of the first section a length generally
equal to a distance between the leading and trailing edges of the
generally elongated airfoil.
5. The turbine vane of claim 3, wherein the projection extends
along the first side edge of the first section a length generally
equal to a distance between the upstream edge to the downstream
edge of the first section and wherein the projection is received
within the groove in the generally elongated airfoil and within
grooves in the first side edge of the second section.
6. The turbine vane of claim 1, wherein the second side edge of the
first section is shaped with a cutaway section that fits around an
outer surface of the generally elongated airfoil.
7. The turbine vane of claim 1, wherein the second endwall is
formed from at least first and second sections positioned adjacent
to each other such that each section forms a releasable joint with
the generally elongated airfoil.
8. The turbine vane of claim 7, wherein the first section of the
second endwall includes a hot gas path surface generally orthogonal
to the generally elongated airfoil, a cold side surface opposite to
the hot gas path surface, an upstream edge, a downstream edge
opposite to the upstream edge, and first and second side edges
opposite to each other, wherein the first side edge of the first
section of the second endwall is positioned in close proximity with
the generally elongated airfoil; wherein the first section of the
second endwall includes a third section attachment system on the
first side edge of the first section, the third section attachment
system being formed from at least one loading bearing surface for
transferring loads from the generally elongated airfoil to the
first section so that the first section supports and positions the
turbine vane within a turbine engine and including at least one
cooling fluid channel on the first side edge that is defined by the
first side edge of the first section of the second endwall and the
outer surface of the generally elongated airfoil to cool a region
of the airfoil at an intersection between the generally elongated
airfoil and the first section, wherein the at least one cooling
fluid channel creates a cooling fluid pathway for cooling fluids to
flow between the first section of the second endwall and the
generally elongated airfoil.
9. The turbine vane of claim 8, wherein the second section of the
second endwall includes a hot gas path surface generally orthogonal
to the generally elongated airfoil, a cold side surface opposite to
the hot gas path surface, an upstream edge, a downstream edge
opposite to the upstream edge, and first and second side edges
opposite to each other, wherein the first side edge of the second
section of the second endwall is positioned in close proximity with
the generally elongated airfoil; wherein the second section of the
second endwall includes a fourth section attachment system on the
first side edge of the second section, the fourth section
attachment system being formed from at least one loading bearing
surface for transferring loads from the generally elongated airfoil
to the second section of the second endwall so that the second
section of the second endwall supports and positions the turbine
vane within a turbine engine and including at least one cooling
fluid channel on the first side edge that is defined by the first
side edge of the second section of the second endwall and the outer
surface of the generally elongated airfoil to cool a region of the
airfoil at an intersection between the generally elongated airfoil
and the second section, wherein the at least one cooling fluid
channel creates a cooling fluid pathway for cooling fluids to flow
between the second section of the second endwall and the generally
elongated airfoil.
10. The turbine vane of claim 9, wherein the at least one load
bearing surface of the third section attachment system is
positioned on a projection extending from the first side edge of
the first section that is received within a groove in the generally
elongated airfoil.
11. The turbine vane of claim 9, wherein the projection extends
along the first side edge of the first section of the second
endwall a length generally equal to a distance between the leading
and trailing edges of the generally elongated airfoil.
12. The turbine vane of claim 9, wherein the projection extends
along the first side edge of the first section of the second
endwall a length generally equal to a distance between the upstream
edge to the downstream edge of the first section and wherein the
projection is received within the groove in the generally elongated
airfoil and within grooves in the first side edge of the second
section of the second endwall.
13. The turbine vane of claim 8, wherein the second side edge of
the first section of the second endwall is shaped with a cutaway
section that fits around an outer surface of the generally
elongated airfoil.
14. A turbine vane, comprising: a generally elongated airfoil
formed from an outer wall, and having a leading edge, a trailing
edge, a pressure side, and a suction side, a first endwall at a
first end, a second endwall at a second end opposite the first end;
wherein the first endwall is formed from at least first and second
sections positioned adjacent to each other such that each section
forms a releasable joint with the generally elongated airfoil, and
wherein the second endwall is formed from at least first and second
sections positioned adjacent to each other such that each section
forms a releasable joint with the generally elongated airfoil;
wherein the first and second sections of the first and second
endwalls each include a hot gas path surface generally orthogonal
to the generally elongated airfoil, a cold side surface opposite to
the hot gas path surface, an upstream edge, a downstream edge
opposite to the upstream edge, and first and second side edges
opposite to each other, wherein the first side edge is positioned
in close proximity with the generally elongated airfoil; wherein
the first section of the first endwall includes a first section
attachment system on the first side edge of the first section of
the first endwall, the first section attachment system being formed
from at least one loading bearing surface for transferring loads
from the generally elongated airfoil to the first section of the
first endwall so that the first section supports and positions the
turbine vane within a turbine engine and including at least one
cooling fluid channel on the first side edge that is defined by the
first side edge of the first section of the first endwall and the
outer surface of the generally elongated airfoil to cool a region
of the airfoil at an intersection between the generally elongated
airfoil and the first section, wherein the at least one cooling
fluid channel creates a cooling fluid pathway for cooling fluids to
flow between the first section and the generally elongated airfoil;
wherein the second section of the first endwall includes a second
section attachment system on the first side edge of the second
section of the first endwall, the second section attachment system
being formed from at least one loading bearing surface for
transferring loads from the generally elongated airfoil to the
second section of the first endwall so that the first section
supports and positions the turbine vane within a turbine engine and
including at least one cooling fluid channel on the first side edge
that is defined by the first side edge of the second section of the
first endwall and the outer surface of the generally elongated
airfoil to cool a region of the airfoil at an intersection between
the generally elongated airfoil and the second section, wherein the
at least one cooling fluid channel creates a cooling fluid, pathway
for cooling fluids to flow between the second section of the first
endwall and the generally elongated airfoil; wherein the first
section of the second endwall includes a third section attachment
system on the first side edge of the first section of the second
endwall, the third section attachment system being formed from at
least one loading bearing surface for transferring loads from the
generally elongated airfoil to the first section of the second
endwall so that the first section supports and positions the
turbine vane within a turbine engine and including at least one
cooling fluid channel on the first side edge that is defined by the
first side edge of the first section of the second endwall and the
outer surface of the generally elongated airfoil to cool a region
of the airfoil at an intersection between the generally elongated
airfoil and the first section, wherein the at least one cooling
fluid channel creates a cooling fluid pathway for cooling fluids to
flow between the first section and the generally elongated airfoil;
wherein the second section of the second endwall includes a fourth
section attachment system on the first side edge of the second
section of the second endwall, the fourth section attachment system
being formed from at least one loading bearing surface for
transferring loads from the generally elongated airfoil to the
second section of the second endwall so that the first section
supports and positions the turbine vane within a turbine engine and
including at least one cooling fluid channel on the first side edge
that is defined by the first side edge of the second section of the
second endwall and the outer surface of the generally elongated
airfoil to cool a region of the airfoil at an intersection between
the generally elongated airfoil and the second section, wherein the
at least one cooling fluid channel creates a cooling fluid pathway
for cooling fluids to flow between the second section of the second
endwall and the generally elongated airfoil.
Description
FIELD OF THE INVENTION
[0001] This invention is directed generally to stationary turbine
vanes, and more particularly to platforms of turbine vanes.
BACKGROUND
[0002] Typically, gas turbine engines include a compressor for
compressing air, a combustor for mixing the compressed air with
fuel and igniting the mixture, and a turbine blade assembly for
producing power. Combustors often operate at high temperatures that
may exceed 2,500 degrees Fahrenheit. Typical turbine combustor
configurations expose turbine vane and blade assemblies to high
temperatures. As a result, turbine vanes and blades must be made of
materials capable of withstanding such high temperatures, or must
include cooling features to enable the component to survive in an
environment which exceeds the capability of the material. Turbine
engines typically include a plurality of rows of stationary turbine
vanes extending radially inward from a shell and include a
plurality of rows of rotatable turbine blades attached to a rotor
assembly for turning the rotor.
[0003] Typically, the turbine vanes 4 are formed from inner and
outer endwalls attached to an airfoil extending therebetween. The
endwalls extend generally orthogonally outward from a longitudinal
axis of the turbine vanes. Typically, advanced turbine vanes are
made by investment casting which are then put through a series of
machining processes and assembly processes to incorporate the
cooling circuit. Fillets are formed at the intersection between the
airfoil and the endwalls. Turbine vanes may be cantilevered and
supported at the ID and OD ends of the turbine vanes which is
typical of stages beyond the first stage vane, or may be simply
supported, which is typical of a first stage vane. Such support
schemes for turbine vanes provide fail-safe support structures
operable under extreme structural and thermal loading. The endwalls
of the turbine vanes are typically butted together at joints that
are remote from the airfoils of the turbine vanes, as shown in FIG.
1. Typically, cooling fluids leak through these joints. The cooling
fluid leakage does not ordinarily provide significant benefit to
the turbine engine in which the turbine vane is positioned. Rather,
the cooling fluid leakage negatively effects the efficiency of the
turbine engine. During use, high temperatures and high stresses are
typically found at the fillets at the intersection of the airfoil
and the endwalls. Traditionally, cooling the fillet has proven to
be very difficult. The high temperature and high stresses in this
region often cause cracking of the vane shroud thereby causing
reduced part life and increased expense. Thus, a need exists for a
turbine vane with a cooling scheme for cooling the region at the
intersection between the turbine airfoil and the endwalls.
SUMMARY OF THE INVENTION
[0004] This invention relates to a turbine vane with endwalls
formed from two or more sections having joints along the airfoils.
The sections may be configured such that the sections form
releasable joints with a generally elongated airfoil of the turbine
vane. The airfoil may incorporate a serpentine cooling circuit and
internal impringement cooling of any variety of cooling circuits
used to cool turbine airfoils. The sections may be configured to
support the generally elongated airfoil and to establish cooling
fluid flowpaths between the sections and the generally elongated
airfoil to cool the aspects of the turbine vane proximate to the
intersection of the endwalls and the generally elongated airfoil.
In addition, the joints between the generally elongated airfoil and
the sections may be formed from a connection system that enables
forces to be transmitted from the generally elongated airfoil to
the endwalls without creating thermal stresses found in
conventional turbine vane fillets at the intersection between the
generally elongated airfoil and the endwalls.
[0005] The turbine vane may be formed from a generally elongated
airfoil formed from an outer wall, and having a leading edge, a
trailing edge, a pressure side, and a suction side, a first endwall
at a first end, and a second endwall at a second end opposite the
first end. The first and second endwalls may be formed from at
least first and second sections positioned adjacent to each other
such that each section forms a releasable joint with the generally
elongated airfoil. The first and second sections of the first and
second endwalls may each include a hot gas path surface that is
generally orthogonal to the generally elongated airfoil, a cold
side surface opposite to the hot gas path surface, an upstream
edge, a downstream edge opposite to the upstream edge, and first
and second side edges opposite to each other. The first side edge
of the first section and the second side edge of the second section
may be positioned in close proximity with the generally elongated
airfoil.
[0006] The first section may include a first section attachment
system on the first side edge of the first section. The first
section attachment system may be formed from at least one loading
bearing surface for transferring loads from the generally elongated
airfoil to the first section so that the first section supports and
positions the turbine vane within a turbine engine. The first
section attachment system may include at least one cooling fluid
channel on the first side edge that is defined by the first side
edge of the first section and the outer surface of the generally
elongated airfoil to cool a region of the airfoil at an
intersection between the generally elongated airfoil and the first
section. Alternately, the airfoil may be the load bearing member
and the first section may be attached to the airfoil transferring
load from the section, to the airfoil. The at least one cooling
fluid channel may create a cooling fluid pathway for cooling fluids
to flow between the first section and the generally elongated
airfoil. The first section attachment system does not include
cooling fluid channels between the upstream edge and the leading
edge of the airfoil and between the trailing edge of the airfoil
and the downstream edge of the section. Alternatively, the design
may be created such that a seal is placed in the region of the
joint to minimize leakage in the region between the upstream edge
and the leading edge of the airfoil and between the trailing edge
of the airfoil and the downstream edge of the section.
[0007] At least one load bearing surface of the first section
attachment system may be positioned on a projection extending from
the first side edge of the first section that is received within a
groove in the generally elongated airfoil. The projection may
extend along the first side edge of the first section a length
generally equal to a distance between the leading and trailing
edges of the generally elongated airfoil. In another embodiment,
the projection may extend along the first side edge of the first
section a length generally equal to a distance between the upstream
edge to the downstream edge of the first section. The projection
may be received within the groove in the generally elongated
airfoil and within grooves in the second side edge of the second
section. The second side edge of the first section may be shaped
with a cutaway section that fits around an outer surface of the
generally elongated airfoil. In an alternate embodiment, the at
least one load bearing surface may be attached to the airfoil with
bolts, clamps or other mechanical means which employ a protrusion
from the lower part of the section which is mechanically attached
to the airfoil through bolts, hooks, clamps, or other mechanical
means.
[0008] The second section of the first endwall may include a second
section attachment system configured similarly to the first section
attachment system. In addition, the first and second section
attachment systems may be configured to attach together in regions
upstream from the leading edge of the turbine airfoil and
downstream from the trailing edge of the turbine airfoil where the
adjacent sections contact each other. Similarly, the first and
second sections of the second endwall may include third and fourth
section attachment systems, thereby forming a single component with
a plurality of airfoils.
[0009] An advantage of this invention is that the joint between
adjacent endwalls for turbine vanes is positioned at the
intersections of a turbine airfoil and the endwalls. Such a
configuration enables the cooling fluids to be exhausted at the
intersection of the turbine airfoil of the turbine vane and the
endwalls, thereby cooling a region that has been traditionally
difficult to cool.
[0010] Another advantage of this invention is that the attachment
system for attaching the endwalls to the turbine airfoil includes
one or more cooling channels for providing cooling fluid pathways
through the load bearing surfaces at the joints to provide cooling
fluids to form film cooling while enabling loads to be transferred
from the endwalls airfoil and vice versa. The cooling channels may
be individually sized and configured to optimize cooling of the
adjacent region of the airfoil.
[0011] Yet another advantage of this invention is that by forming
an endwall from a plurality of sections that are releasably joined
together, components of the turbine vane, such as the sections and
airfoil, may be easily replaced in a cost effective manner.
[0012] Another advantage of this invention is that the turbine vane
uses cooling fluids that were previously wasted in conventional
systems by being exhausted through joints positioned in a
non-optimized region between adjacent turbine vanes.
[0013] Still another advantage of this invention is that the
turbine vane eliminates stresses because a rigid connection such as
that which exists in a single piece casting as the welded
intersection is not required between the airfoil and endwall of
conventional systems.
[0014] Another advantage of this invention is that the
configuration of the turbine vane may be easily changed. For
instance, the angle of position of the turbine vane may be easily
changed by removing the sections of the turbine vane and replacing
them with alternate sections that cause the vane to be oriented in
a different angle in the gas path. Because the turbine airfoil of
the turbine vane may be so easily replaced, the turbine vane may be
easily customized to a particular load application for increased
efficiency.
[0015] These and other embodiments are described in more detail
below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The accompanying drawings, which are incorporated in and
form a part of the specification, illustrate embodiments of the
presently disclosed invention and, together with the description,
disclose the principles of the invention.
[0017] FIG. 1 is an end view of conventional turbine vanes
positioned adjacent one another in a turbine engine with joints of
adjacent endwalls between,the airfoils.
[0018] FIG. 2 is an end view of turbine vanes of the instant
invention.
[0019] FIG. 3 is a perspective view of a turbine vane of this
invention with first and second endwalls.
[0020] FIG. 4 is a perspective view of a partial turbine vane of
this invention with only a first sidewall.
[0021] FIG. 5 is a perspective view of a partial turbine vane of
this invention with a first section forming a portion of the first
endwall.
[0022] FIG. 6 is a detailed cross-section of an attachment system
taken at detail line 6-6 in FIG. 3 usable to attach the endwalls to
the generally elongated airfoil of the turbine vane.
[0023] FIG. 7 is a partial detail view of an attachment system
formed from a protrusion with cooling fluid channels.
[0024] FIG. 8 is a partial detail view of another embodiment of the
attachment system formed from a protrusion with cooling fluid
channels.
[0025] FIG. 9 is a detailed cross-section of another embodiment of
the attachment system shown in FIG. 6.
[0026] FIG. 10 is a front view of a side edge of a section with a
protrusion having load bearing surfaces and cooling channels taken
at line 10-10 in FIG. 7.
[0027] FIG. 11 is a front view of a side edge of a section with a
protrusion having an alternative configuration of load bearing
surfaces and cooling channels taken at line 11-11 in FIG. 8.
DETAILED DESCRIPTION OF THE INVENTION
[0028] As shown in FIGS. 2-11, this invention is directed to a
turbine vane 10 with endwalls 12 formed from two or more sections
14. The sections 14 may be configured such that the sections 14
form releasable joints 18 with a generally elongated airfoil 16 of
the turbine vane 10 at the airfoil 16. The sections 14 may be
configured 14 to both support the generally elongated airfoil 16
and to establish cooling fluid flowpaths between the sections 14
and the generally elongated airfoil 16 to cool the aspects of the
turbine vane 10 proximate to the intersection of the endwalls 12
and the generally elongated airfoil 16. In addition, the joints 18
between the generally elongated airfoil 16 and the sections 14 may
be formed from a connection system that enables forces to be
transmitted from the generally elongated airfoil 16 to the endwalls
12 without creating stresses found in conventional turbine vane
fillets at the intersection between the generally elongated airfoil
16 and the endwalls 12.
[0029] As shown in FIGS. 4 and 5, the turbine vane 10 may be formed
from a generally elongated airfoil 16 formed from an outer wall 20,
and having a leading edge 22, a trailing edge 24, a pressure side
26, and a suction side 28, a first endwall 30 at a first end 32,
and a second endwall 34 at a second end 36 opposite the first end
32. The generally elongated airfoil 16 may have any appropriate
profile configured for use in a turbine engine.
[0030] The endwalls 12 of the turbine vane 10 support and position
the generally elongated airfoil 16 within a turbine engine. The
endwalls 12 are thus configured to transfer loads (forces) from the
generally elongated airfoil 16 to the endwalls 12. In particular,
one or both of the endwalls 12 may be formed from two or more
sections 14. As shown in FIG. 2-4, an endwall 12, such as the first
endwall 30, may be formed from a first section 38 and a second
section 40. The sections 38, 40 may each include a hot gas path
surface 42, 44 positioned generally orthogonal to the generally
elongated airfoil 16, a cold side surface 46, 48 opposite to the
hot gas path surface 42, 44, an upstream edge 50, 52, a downstream
edge 54, 56 opposite to the upstream edge 50, 52, and a first side
edge 58, 60 and a second side edge 62, 64 opposite to each other,
respectively. The first and second sections 38, 40 may be
configured such that the upstream edges 50, 52 are positioned
upstream from the leading edge 22, and the downstream edges 54, 56
are positioned downstream from the trailing edge 24. As such, the
first and second sections 38, 40 may contact each other upstream
from the leading edge 22 and downstream of the trailing edge 24 of
the generally elongated airfoil 16. The first and second sections
38, 40 may include cutaway airfoil sections 66, 68 that correspond
to the pressure and suction sides 26, 28 of the generally elongated
airfoil 16, respectively. The cutaway airfoil sections 66, 68
enable the generally elongated airfoil 16 to fit within the cutaway
airfoil sections 66, 68 and for the first and second sections 38,
40 to form joints 18 with each other upstream and downstream from
the generally elongated airfoil 16. The joints 18 upstream and
downstream from the generally elongated airfoil 16 may be aligned
with a midline of the turbine vane 10, as shown in FIG. 2.
[0031] The first side edge 58 of the first section 38 may be
positioned in close proximity with pressure side 26 of the
generally elongated airfoil 16 and the second side edge 64 of the
second section 40 may be positioned in close proximity with the
suction side 28 of the generally elongated airfoil 16. The first
side edges 58, 60 and the second side edges 62, 64 of the first and
second sections 38, 40 may be configured to form joints 18 with the
generally elongated airfoil 16, as described in more detail
below.
[0032] The turbine vane 10 may also include a first section
attachment system 70 on the first side edge 58 of the first section
38, the first section attachment system 70 may be formed from at
least one load bearing surface 72 for transferring loads from the
generally elongated airfoil 16 to the first section 38 so that the
first section 38 supports and positions the turbine vane 10 within
a turbine engine. The load bearing surface 72 may be formed from
one or more load bearing surfaces 72 positioned at the cutaway
section 66. The first section attachment system 70 may include at
least one cooling fluid channel 74 on the first side edge 58 that
is defined by the first side edge 58 of the first section 38 and
the outer surface 20 of the generally elongated airfoil 16 to cool
a region of the airfoil 16 at an intersection between the generally
elongated airfoil 16 and the first section 38. The cooling fluid
channel 74 may create a cooling fluid pathway for cooling fluids to
flow between the first section 38 and the generally elongated
airfoil 16.
[0033] The cooling fluid channel 74 may be formed from various
appropriate configurations. For instance, the cooling fluid channel
74 may have a semicircular cross-sectional shape, as shown in FIG.
7 and 10, a slight depression in the first side edge 58, as shown
in FIG. 8 and 11, or have another appropriate shape enabling
cooling fluids to move from an internal cooling system to the hot
gas path. The size of the cooling fluid channel 74 may be used to
control the flow of cooling fluids through the cooling fluid
channel 74. The load bearing surface 72 may extend across the
entire cutaway airfoil section 66 with cooling fluid channels 74
interspersed along the length of the cutaway airfoil section 66 to
enable cooling fluids to flow between the first side edge 58 and
the generally elongated airfoil 16.
[0034] In one embodiment, as shown in FIG. 6, the first section
attachment system 70 may be formed from a projection 76 extending
from the first side edge 58 and a groove 78 in the generally
elongated airfoil 16 for receiving the projection 76. The load
bearing surface 72 may be positioned on the projection 76 where the
projection 76 contacts the generally elongated airfoil 16 in the
groove 78. The cooling fluid channels 74 may be positioned on the
lower surface 80 of the projection 76 to create a cooling fluid
pathway enabling cooling fluids to pass from a cooling fluid supply
source into the hot gas path. In one embodiment, as shown in FIG.
4, the projection 76 may extend along the first side edge 58 of the
first section 38 a length generally equal to a distance between the
upstream edge 50 to the downstream edge 54 of the first section 38.
The projection 76 may be received within the groove 78 in the
generally elongated airfoil 16 and within grooves 78 in the second
side edge 64 of the second section 40 upstream and downstream from
the cutaway airfoil section 68.
[0035] The second section 40 may include a second section
attachment system 82 for attaching the second section 40 to the
generally elongated airfoil 16. The second section attachment
system 82 may configured similarly to the first attachment system
82. In particular, the second section attachment system 82 may
include a projection 76 on the second side edge 64 of the second
section 40. The projection 76 may be received within a groove 78 in
the generally elongated airfoil 16. The projection 76 may extend
only within the cutaway airfoil section 68. Sections of the second
side edge 64 between the cutaway airfoil section 68 and the
upstream edge 52 and between the cutaway airfoil section 68 and the
downstream edge 56 may include grooves 78 to receive the projection
76 extending from the first side edge 58 of the first section 38.
In another embodiment, the configuration of the first and second
sections 38, 40 may be reversed such that the projection 76 extends
entirely down the second section 40 and only down a portion of the
first side edge 58 of the first section 38.
[0036] The second endwall 34 may be formed in a configuration
similar to the first endwall 30. In particular, the second endwall
34, may be formed from a first section 90 and a second section 92.
The sections 90, 92 may each include a hot gas path surface 94, 96
positioned generally orthogonal to the generally elongated airfoil
16, a cold side surface 98, 100 opposite to the hot gas path
surface 94, 96, an upstream edge 102, 104, a downstream edge 106,
108 opposite to the upstream edge 102, 104, and a first side edge
110, 112 and a second side edge 114, 116 opposite to each other,
respectively. The first and second sections 90, 92 may be
configured such that the upstream edges 102, 104 are positioned
upstream from the leading edge 22, and the downstream edges 106,
108 are positioned downstream from the trailing edge 24. As such,
the first and second sections 90, 92 may contact each other
upstream from the leading edge 22 and downstream of the trailing
edge 24 of the generally elongated airfoil 16. The first and second
sections 90, 92 may include cutaway airfoil sections 118, 120 that
correspond to the pressure and suction sides 26, 28 of the
generally elongated airfoil 16, respectively. The cutaway airfoil
sections 118, 120 enable the generally elongated airfoil 16 to fit
within the cutaway airfoil sections 118, 120 and for the first and
second sections 90, 92 to form joints 18 with each other upstream
and downstream from the generally elongated airfoil 16. The joints
18 upstream and downstream from the generally elongated airfoil 16
may be aligned with a midline of the turbine vane 10, as shown in
FIG. 2.
[0037] The first side edge 110 of the first section 90 may be
positioned in close proximity with pressure side 26 of the
generally elongated airfoil 16 and the second side edge 116 of the
second section 92 may be positioned in close proximity with the
suction side 28 of the generally elongated airfoil 16. The first
side edges 110, 112 and the second side edges 114, 116 of the first
and second sections 90, 92 may be configured to form joints 18 with
the generally elongated airfoil 16, as described in more detail
below.
[0038] The turbine vane 10 may also include a third section
attachment system 122 on the first side edge 110 of the first
section 90, the third section attachment system 122 may be formed
from at least one load bearing surface 124 for transferring loads
from the generally elongated airfoil 16 to the first section 90 so
that the first section 90 supports and positions the turbine vane
10 within a turbine engine. The load bearing surface 124 may be
formed from one or more load bearing surfaces 124 positioned at the
cutaway section 118. The third section attachment system 122 may
include at least one cooling fluid channel 126 on the first side
edge 110 that is defined by the first side edge 110 of the first
section 90 and the outer surface 20 of the generally elongated
airfoil 16 to cool a region of the airfoil 16 at an intersection
between the generally elongated airfoil 16 and the first section
90. The cooling fluid channel 126 may create a cooling fluid
pathway for cooling fluids to flow between the first section 90 and
the generally elongated airfoil 16.
[0039] The cooling fluid channel 126 may be formed from various
appropriate configurations. For instance, the cooling fluid channel
126 may have a semicircular cross-sectional shape, as shown in
FIGS. 7 and 10, a slight depression in the first side edge 110, as
shown in FIGS. 8 and 11, or have another appropriate shape enabling
cooling fluids to move from an internal cooling system to the hot
gas path. The size of the cooling fluid channel 126 may be used to
control the flow of cooling fluids through the cooling fluid
channel 126. The load bearing surface 124 may extend across the
entire cutaway airfoil section 118 with cooling fluid channels 126
interspersed along the length of the cutaway airfoil section 118 to
enable cooling fluids to flow between the first side edge 110 and
the generally elongated airfoil 16.
[0040] In one embodiment, as shown in FIG. 6, the third section
attachment system 122 may be formed from a projection 128 extending
from the first side edge 110 and a groove 130 in the generally
elongated airfoil 16 for receiving the projection 128. The load
bearing surface 124 may be positioned on the projection 128 where
the projection 128 contacts the generally elongated airfoil 16 in
the groove 130. The cooling fluid channels 126 may be positioned on
the upper surface 80 of the projection 128 to create a cooling
fluid pathway enabling cooling fluids to pass from a cooling fluid
supply source into the hot gas path. In one embodiment, as shown in
FIG. 4, the projection 128 may extend along the first side edge 110
of the first section 90 a length generally equal to a distance
between the upstream edge 102 to the downstream edge 106 of the
first section 90. The projection 128 may be received within the
groove 130 in the generally elongated airfoil 16 and within grooves
130 in the second side edge 116 of the second section 92 upstream
and downstream from the cutaway airfoil section 120.
[0041] The second section 92 may include a fourth section
attachment system 132 for attaching the second section 92 to the
generally elongated airfoil 16. The fourth section attachment
system 132 may configured similarly to the third attachment system
122. In particular, the fourth section attachment system 132 may
include a projection 128 on the second side edge 116 of the second
section 92. The projection 128 may be received within a groove 130
in the generally elongated airfoil 16. The projection 128 may
extend only within the cutaway airfoil section 120. Sections of the
second side edge 116 between the cutaway airfoil section 120 and
the upstream edge 104 and between the cutaway airfoil section 120
and the downstream edge 108 may include grooves 130 to receive the
projection 128 extending from the first side edge 110 of the first
section 90. In another embodiment, the configuration of the first
and second sections 90, 92 may be reversed such that the projection
128 extends entirely down the second section 92 and only down a
portion of the first side edge 110 of the first section 90.
[0042] During use, the turbine vane 10 and corresponding first and
second sections 38, 40, 90, 92 forming the first and second
endwalls 30, 34, respectively, form an efficient cooling system
that eliminates stress related problems that are created at fillets
in conventional turbine vanes at the intersection between endwalls
and the airfoil. During use, the generally elongated airfoil 16 is
held stationary in the turbine engine. The outboard endwall 34
supports the airfoil 16, which in turn supports the inboard endwall
30 and inner support ring (not shown). During use, cooling fluids
are passed through internal aspects of the airfoil 16 to cool the
airfoil and to supply cooling fluids to the rotor assembly. Cooling
fluids may be leaked through the cooling fluid channels 74, 126 in
the inner and outer endwalls 30, 34. The cooling fluids may be
released at the intersection between the airfoil 16 and the
endwalls 30, 34, thereby providing film cooling in a region that
traditionally has been very difficult to cool. The efficiency of
the turbine engine for a particular load application may be
optomized by testing the engine with turbine vanes having different
angles of alignment relative to the flow path of hot combustion
gases. Such testing may be accomplished relatively
inexpensively.
[0043] The foregoing is provided for purposes of illustrating,
explaining, and describing embodiments of this invention.
Modifications and adaptations to these embodiments will be apparent
to those skilled in the art and may be made without departing from
the scope or spirit of this invention.
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