U.S. patent application number 15/328984 was filed with the patent office on 2017-08-03 for modular turbine blade with separate platform support system.
The applicant listed for this patent is Siemens Energy, Inc.. Invention is credited to Christian Xavier Campbell, Darryl Eng, Samuel R. Miller, JR..
Application Number | 20170218782 15/328984 |
Document ID | / |
Family ID | 51541299 |
Filed Date | 2017-08-03 |
United States Patent
Application |
20170218782 |
Kind Code |
A1 |
Miller, JR.; Samuel R. ; et
al. |
August 3, 2017 |
MODULAR TURBINE BLADE WITH SEPARATE PLATFORM SUPPORT SYSTEM
Abstract
A modular turbine blade assembly (10) usable in a gas turbine
engine (12) and formed from an airfoil (28) and an independent,
modular platform (16) supported by one or more clevis arm supports
(14) extending radially inward from the modular platform (16) to a
disk is disclosed. The clevis arm support may support the modular
platform while a separate dovetail attachment supports the
generally hollow airfoil. The clevis arm support (14) may be formed
from at least two arms (20, 22) designed to reduce stress from a
pin receiving orifice (24) at a distal end (26) of the two arms
(20, 22) to the platform (16). The independent arms (20, 22)
minimize stress concentrations caused by centrifugal loading in the
support. The arms (20, 22) may be modified independently of each
other, such as thickness and support angle. The clevis arm support
(14) enables use of a modular platform system for the modular
turbine blade (10).
Inventors: |
Miller, JR.; Samuel R.;
(Port St. Lucie, FL) ; Eng; Darryl; (Stuart,
FL) ; Campbell; Christian Xavier; (Charlotte,
NC) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Siemens Energy, Inc. |
Orlando |
FL |
US |
|
|
Family ID: |
51541299 |
Appl. No.: |
15/328984 |
Filed: |
August 22, 2014 |
PCT Filed: |
August 22, 2014 |
PCT NO: |
PCT/US2014/052249 |
371 Date: |
January 25, 2017 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F01D 5/3053 20130101;
F01D 11/008 20130101; F01D 5/18 20130101; F01D 5/3007 20130101 |
International
Class: |
F01D 5/30 20060101
F01D005/30; F01D 5/18 20060101 F01D005/18 |
Goverment Interests
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0001] Development of this invention was supported in part by the
United States Department of Energy, Advanced Turbine Development
Program, Contract No. DE-FC26-05NT42644. Accordingly, the United
States Government may have certain rights in this invention.
Claims
1. A modular turbine blade (10) of a gas turbine engine comprising:
a generally elongated hollow airfoil formed from an outer wall, and
having a leading edge, a trailing edge, a pressure side, a suction
side, and a tip at a first end of the airfoil; and a modular
platform attached to a disc via at least one clevis arm support
extending radially inward from the modular platform, wherein the at
least one clevis arm support is formed from a first arm and a
second arm extending from the modular platform into contact with
each other radially inward of the modular platform, wherein a cross
member extends between the first and second arms forming an
attachment device radially inward of the cross member and between
the first and second arms and forming a void between the cross
member, the first arm, the second arm and the modular platform.
2. The modular turbine blade of claim 1, wherein the attachment
device is a pin receiving orifice.
3. The modular turbine blade of claim 1, wherein at least one
intersection of two or more sides forming the cross member, the
first arm, and the second arm is rounded.
4. The modular turbine blade of claim 1, wherein inner surfaces of
the first arm, the second arm and the cross member are planar inner
surfaces.
5. The modular turbine blade of claim 1, wherein a thickness of the
first arm differs from a thickness of the second arm.
6. The modular turbine blade of claim 1, wherein the first arm has
a cross-sectional area with a width that is greater than a length,
and the second arm has a cross-sectional area with a width that is
greater than a length.
7. The modular turbine blade of claim 1, wherein the first and
second arms are nonorthogonal and nonparallel to each other.
8. The modular turbine blade of claim 7, wherein the first arm is
positioned at a different angle relative to a longitudinal axis of
the at least one clevis arm support than the second arm.
9. The modular turbine blade of claim 1, wherein first ends of the
first and second arms closest to the generally elongated hollow
airfoil are further apart than second ends of the first and second
arms at the cross member.
10. The modular turbine blade of claim 1, wherein a distal end of
the cross member is curved from a first side aligned with the first
arm to a second side aligned with the second arm.
11. The modular turbine blade of claim 1, further wherein a center
link extending radially inward from the modular platform and
positioned between the first and second arms.
12. The modular turbine blade of claim 11, wherein the center link
is coupled to the modular platform via a pivot connection.
Description
FIELD OF THE INVENTION
[0002] This invention is directed generally to turbine airfoils,
and more particularly to support systems in turbine airfoils in gas
turbine engines.
BACKGROUND
[0003] 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 2,240 degrees Fahrenheit. Typical turbine combustor
configurations expose turbine blade assemblies to these high
temperatures. As a result, turbine blades must be made of materials
capable of withstanding such high temperatures. In addition,
turbine blades often contain cooling systems for prolonging the
life of the blades and reducing the likelihood of failure as a
result of excessive temperatures.
[0004] Typically, turbine blades are formed from a root portion
having a platform at one end and an elongated portion forming a
blade that extends outwardly from the platform coupled to the root
portion. The blade is ordinarily composed of a tip opposite the
root section, a leading edge, and a trailing edge. The inner
aspects of most turbine blades typically contain an intricate maze
of cooling channels forming a cooling system. Turbine airfoils are
often supported via a root having multiple dovetail projections
extending therefrom for attachment to a rotor. Alternative
configurations of a support and connection system have been
employed.
SUMMARY OF THE INVENTION
[0005] A modular turbine blade assembly usable in a gas turbine
engine and formed from an airfoil and an independent, modular
platform supported by one or more clevis arm supports extending
radially inward from the modular platform to a disk is disclosed.
The clevis arm support may support the modular platform while a
separate dovetail attachment supports the generally hollow airfoil.
The clevis arm support may be formed from one or more arms, such
as, but not limited to, two arms, a first and second arm, that may
be independently modified to reduce stress at an attachment device
at a distal end of the two arms. In at least one embodiment, the
attachment device may be a pin receiving orifice. The independent
arms may be contoured for assembly between blades and designed to
minimize stresses along clevis arm features. At attachment
locations, one or more pin receiving orifices may be included at
distal ends of the two arms.
[0006] The modular turbine blade for a gas turbine engine may be
formed from a generally elongated hollow airfoil formed from an
outer wall, and having a leading edge, a trailing edge, a pressure
side, a suction side, and a tip at a first end of the airfoil. The
clevis arm support may support the modular platform while a
separate dovetail attachment supports the generally hollow airfoil.
The modular turbine blade may also include one or more modular
platforms attached to a disc via clevis arm supports extending
radially inward from the modular platform. The clevis arm support
may be formed from a first arm and a second arm extending from the
modular platform into contact with each other radially inward of
the modular platform. A cross member may extend between the first
and second arms forming an attachment device, such as, but not
limited to, a pin receiving orifice radially inward of the cross
member and between the first and second arms and forming a void
between the cross member, the first arm, the second arm and the
modular platform. In at least one embodiment, inner surfaces of the
first arm, the second arm and the cross member may be planar inner
surfaces.
[0007] The first and second arms may reduce stress at the pin
receiving orifice at a distal end of the two arms. The clevis arm
support may reduce stress in a number of ways. In particular, the
first and second arms may be nonorthogonal and nonparallel to each
other. The first arm may be positioned at a different angle
relative to a longitudinal axis of the at least one clevis arm
support than the second arm. One or more intersections of two or
more sides forming the cross member, the first arm, and the second
arm may be rounded. In another embodiment, each of the
intersections of two or more sides forming the cross member, the
first arm, and the second arm may be rounded. A thickness of the
first arm may differ from a thickness of the second arm. The first
arm may have a cross-sectional area with a width that is greater
than a length, and the second arm may have a cross-sectional area
with a width that is greater than a length. The first ends of the
first and second arms closest to the generally elongated hollow
airfoil may be further apart than second ends of the first and
second arms at the cross member. A distal end of the cross member
may be curved from a first side aligned with the first arm to a
second side aligned with the second arm.
[0008] During assembly, the center link may be pinned at the
platform and may be rotated around and between the airfoil into the
disk, which helps facilitate the installation and alignment with
the pin, pin receiving orifices and disk holes. During operation,
the first and second clevis arms and pin inherently provide the
ability to rotate along the pin axis through the pin receiving
orifices to load the modular platform against the pressure side of
the generally elongated hollow airfoil for sealing and vibratory
dampening. For servicing or assembly, or both, the modular turbine
blade assembly provides a configuration that makes the option of
removing or replacing the platform, or both, while the blade
remains attached in place in turbine engine possible. This feature
is very beneficial in that the modular turbine blade assembly
provides a lower cost replacement in contrast to repairing and
replacing a full blade during service intervals.
[0009] An advantage of the modular platform is the ability to
improve the castability of the airfoil by minimizing overhang
features, which is primarily for single crystal airfoils. The
platform can utilize a less challenging casting method such as
directional/non directional solidification or single crystal if
warranted.
[0010] Another advantage of the modular turbine blade assembly is
that the pin and clevis hole arrangement provides the ability to be
sized to achieve sufficient pin and clevis arm bearing area while
minimizing stress within the hole. The features of the modular
turbine blade assembly can be easily controlled during the
manufacturing process to create close tolerances between the pin
and holes in the clevis arms.
[0011] Yet another advantage of this the clevis arm support is that
the clevis arm support may be formed from at least two arms, a
first and second arm, that may be independently modified to reduce
stress at a pin receiving orifice at a distal end of the two
arms.
[0012] Another advantage of the clevis arm support is that the
independent arms minimize stress concentrations caused by
centrifugal loading through the support.
[0013] Still another advantage of the clevis arm support is that
the support enables mass reduction to be achieved through use of
the first and second arms of the clevis arm support relative to
conventional attachments.
[0014] These and other embodiments are described in more detail
below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] 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.
[0016] FIG. 1 is a perspective view of a modular turbine blade
having features according to the instant invention.
[0017] FIG. 2 is a perspective view of the clevis arm support of
the modular turbine blade.
[0018] FIG. 3 is a perspective view of the clevis arm support of
the modular turbine blade.
DETAILED DESCRIPTION OF THE INVENTION
[0019] As shown in FIGS. 1-3, a modular turbine blade assembly 10
usable in a gas turbine engine 12 and formed from an airfoil 28 and
an independent, modular platform 16 supported by one or more clevis
arm supports 14 extending radially inward from the modular platform
16 to a disk is disclosed. The clevis arm support 14 may support
the modular platform 16 while a separate dovetail attachment
supports the generally hollow airfoil 28. The clevis arm support 14
may be formed from one or more arms, such as, but not limited to,
two arms, a first arm 20 and second arm 22, that may be
independently modified to reduce stress at an attachment device 24
at a distal end 26 of the two arms 20, 22. The independent arms 20,
22 may be contoured for assembly between blades 28 and designed to
minimize stresses along clevis arm 20, 22 features. The independent
arms 20, 22 minimize stress concentrations caused by centrifugal
loading through the support 14. The arms 20, 22 may be modified
independently of each other, by modifying elements such as
thickness and support angle. With the airfoil 28 being attached to
a disc separately from the modular platform 16, the modular
platform 16 may be removed and replaced without removing the
airfoil 28.
[0020] In at least one embodiment, as shown in FIG. 1, the modular
turbine blade 10 may be formed from a generally elongated hollow
airfoil 28 formed from an outer wall 30, and having a leading edge
32, a trailing edge 34, a pressure side 36, a suction side 38 and a
tip 40 at a first end 42 of the airfoil 28. The clevis arm support
14 may support the modular platform 16 while a separate dovetail
attachment supports the generally hollow airfoil 28. A modular
platform 16 may be positioned at a second end 46 opposite to the
first end 42 and may be supported by one or more clevis arm
supports 14, as shown in FIGS. 1-3, extending radially inward from
the modular platform 16. In at least one embodiment, as shown in
FIG. 2, each clevis arm support 14 may include a first arm 20 sized
to support the attachment device 24, which, in at least one
embodiment, may be a pin receiving orifice 24. The first arm 20 may
be formed from any appropriate configuration such as, but not
limited to, an "I" beam profile. The pin receiving orifice 24 may
have any appropriate size and configuration, such as, but not
limited to, tubular.
[0021] In at least one embodiment, as shown in FIG. 3, the modular
turbine blade 10 may include two clevis arm supports 14 per modular
platform 16. The clevis arm support 14 may be formed from a first
arm 20 and a second arm 22 extending from the modular platform 16
into contact with each other radially inward of the modular
platform 16. The clevis arm support 14 may be formed from any
appropriate material capable of adequately supporting the modular
platform 16 and withstanding the high temperatures, vibrations and
other elements. A cross member 48 may extend between the first and
second arms 20, 22 forming a pin receiving orifice 24 radially
inward of the cross member 48 and between the first and second arms
20, 22 forming a void 52 between the cross member 48, the first arm
20, the second arm 22 and the modular platform 16. The inner
surfaces 58 of the first arm 20, the second arm 22 and the cross
member 48 may be planar inner surfaces 58. In at least one
embodiment, the first ends 76 of the first and second arms 20, 22
closest to the generally elongated hollow airfoil 28 may be further
apart than second ends 78 of the first and second arms 20, 22 at
the cross member 48. A distal end 80 of the cross member 48 may be
curved from a first side 80 aligned with the first arm 20 to a
second side 82 aligned with the second arm 22.
[0022] The first and second arm 20, 22, may reduce stress at the
pin receiving orifice 24 at a distal end 26 of the two arms 20, 22.
The clevis arm support 14 may reduce stress in a number of ways. In
at least one embodiment, one or more intersections 54 of two or
more sides 56 forming the cross member 48, the first arm 20, and
the second arm 22 is rounded. In another embodiment, each of the
intersections 54 of two or more sides 56 forming the cross member
48, the first arm 20, and the second arm 22 is rounded.
[0023] The first and second arm 20, 22, may also reduce stress at
the pin receiving orifice 24 at a distal end 26 of the two arms 20,
22 in other ways. In particular, a thickness 60 of the first arm 20
may differ from a thickness 62 of the second arm 22. The length of
the first and second arms 20 and 22 may be varied as well to reduce
stress and to enable proper positioning of the pin receiving
orifice 24. The first arm 20 may have a cross-sectional area with a
width 64 that is greater than a length 66, and the second arm 22
may have a cross-sectional area with a width 68 that is greater
than a length 70. The first and second arms 20, 22 may be
nonorthogonal and nonparallel to each other. In particular, the
first arm 20 may be positioned at a different angle 72 relative to
a longitudinal axis 74 of the clevis arm support 14 than an angle
84 of the second arm 22 relative to the longitudinal axis 74.
[0024] The modular platform 16 may also include a center link 90
extending radially inward. The center link 90 may include one or
more pin receiving orifices 24, one of which may be positioned near
a distal end 26. The center link 90 may be positioned between the
first and second arms 20, 22. The center link 90 may be coupled to
the modular platform 16 via a pivot connection. The center link 90
may be attached to the modular platform 16 via a pivot connection
formed from a pin 92 extending through a hole in the center link 90
and attached to arms 94, 96 via holes 98, 100 therein. The pin 92
enables the center link 90 to pivot around the blade 28 during
installation and removal and enable minor platform circumferential
differences. The center link 90 may be used for assembly and
support of the center of the modular platform 16 from centrifugal
loading. The center link 90 may assist in minimizing platform
deflections between the first and second clevis arms 20, 22 to
enable the center link 90 to fit around the airfoil contour because
the center of the modular platform 16 is near the blade midchord,
which limits clevis access.
[0025] During assembly, the center link 90 may be pinned at the
platform and may be rotated around and between the airfoil 28 into
the disk, which helps facilitate the installation and alignment
with the pin, pin receiving orifices 24 and disk holes. During
operation, the first and second clevis arms 20, 22 and pin
inherently provide the ability to rotate along the pin axis through
the pin receiving orifices 24 to load the modular platform 16
against the pressure side 36 of the generally elongated hollow
airfoil 28 for sealing and vibratory dampening. For servicing or
assembly, or both, the modular turbine blade assembly 10 provides a
configuration that makes the option of removing or replacing the
platform, or both, while the blade remains attached in place in
turbine engine possible. This feature is very beneficial in that
the modular turbine blade assembly 10 provides a lower cost
replacement in contrast to repairing and replacing a full blade
during service intervals.
[0026] 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.
* * * * *