U.S. patent application number 13/768213 was filed with the patent office on 2014-08-21 for systems and methods for facilitating onboarding of bucket cooling flows.
This patent application is currently assigned to GENERAL ELECTRIC COMPANY. The applicant listed for this patent is GENERAL ELECTRIC COMPANY. Invention is credited to Sushilkumar Babu Mane, Vishal Rajpurohit, Karthik Srinivasan.
Application Number | 20140234070 13/768213 |
Document ID | / |
Family ID | 51351302 |
Filed Date | 2014-08-21 |
United States Patent
Application |
20140234070 |
Kind Code |
A1 |
Srinivasan; Karthik ; et
al. |
August 21, 2014 |
Systems and Methods for Facilitating Onboarding of Bucket Cooling
Flows
Abstract
Systems and methods Embodiments for facilitating onboarding of a
cooling fluid are disclosed herein. According to one embodiment, a
system may include a rotor assembly, a wheel space cavity adjacent
to the rotor assembly, and a bucket shank cavity in fluid
communication with the wheel space cavity. The system may also
include at least one protrusion disposed on the rotor assembly in
the wheel space cavity. The at least one protrusion may be
configured to direct the cooling fluid radially from the wheel
space cavity to the bucket shank cavity to minimize pressure loss
in the cooling fluid.
Inventors: |
Srinivasan; Karthik;
(Bangalore, IN) ; Rajpurohit; Vishal; (Jodhpur,
IN) ; Mane; Sushilkumar Babu; (District Solapur,
IN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
GENERAL ELECTRIC COMPANY |
Schenectady |
NY |
US |
|
|
Assignee: |
GENERAL ELECTRIC COMPANY
Schenectady
NY
|
Family ID: |
51351302 |
Appl. No.: |
13/768213 |
Filed: |
February 15, 2013 |
Current U.S.
Class: |
415/1 ;
415/116 |
Current CPC
Class: |
F01D 5/081 20130101;
F01D 5/187 20130101 |
Class at
Publication: |
415/1 ;
415/116 |
International
Class: |
F01D 25/12 20060101
F01D025/12 |
Claims
1. A turbine system for facilitating onboarding of a cooling fluid,
comprising: a rotor assembly; a wheel space cavity adjacent to the
rotor assembly; a bucket shank cavity in fluid communication with
the wheel space cavity; and at least one protrusion disposed on the
rotor assembly in the wheel space cavity, wherein the at least one
protrusion is configured to direct the cooling fluid from the wheel
space cavity to the bucket shank cavity to minimize pressure loss
in the cooling fluid.
2. The system of claim 1, wherein the at least one protrusion is
positioned on the rotor assembly about an interface between the
wheel space cavity and the bucket shank cavity.
3. The system of claim 2, wherein the at least one protrusion
comprises a plurality of protrusions.
4. The system of claim 3, wherein the plurality of protrusions are
spaced apart adjacent to one another circumferentially on the rotor
assembly about the interface between the wheel space cavity and the
bucket shank cavity.
5. The system of claim 1, wherein the at least one protrusion
comprises a fin.
6. The system of claim 1, further comprising at least one cooling
passage in communication with the bucket shank cavity, wherein the
at least one cooling passage is configured to discharge at least a
portion of the cooling fluid into a hot gas path.
7. The system of claim 6, wherein the cooling fluid comprises a
pressure greater than the hot gas path.
8. The system of claim 1, wherein the cooling fluid comprises
compressor extraction air.
9. The system of claim 1, wherein the bucket shank cavity is
associated with a stage one turbine bucket.
10. A turbine system for facilitating onboarding of a cooling
fluid, comprising: a rotor assembly; a plurality of buckets
attached to the rotor assembly, wherein each of the plurality of
buckets comprises a bucket shank cavity therein; a wheel space
cavity adjacent to the rotor assembly, wherein the bucket shank
cavities are in fluid communication with the wheel space cavity;
and a plurality of protrusions disposed on the rotor assembly in
the wheel space cavity, wherein the plurality of protrusions are
configured to direct the cooling fluid from the wheel space cavity
to the bucket shank cavities to minimize pressure loss in the
cooling fluid.
11. The system of claim 10, wherein the plurality of protrusions
are positioned on the rotor assembly about an interface between the
wheel space cavity and the bucket shank cavities.
12. The system of claim 11, wherein the plurality of protrusions
are spaced apart adjacent to one another circumferentially on the
rotor assembly about the interface between the wheel space cavity
and the bucket shank cavity.
13. The system of claim 10, wherein the plurality of protrusions
comprise fins.
14. The system of claim 10, wherein each of the plurality of
buckets comprises at least one cooling passage in communication
with the bucket shank cavity, wherein the at least one cooling
passage is configured to discharge at least a portion of the
cooling fluid into a hot gas path.
15. The system of claim 14, wherein the cooling fluid in the at
least one cooling passage comprises a pressure greater than the hot
gas path.
16. The system of claim 10, wherein the cooling fluid comprises
compressor extraction air.
17. A method for facilitating onboarding of a cooling fluid to a
bucket, comprising: positioning a bucket shank cavity in fluid
communication with a wheel space cavity; positioning a plurality of
protrusions on a rotor assembly in the wheel space cavity; and
directing the cooling fluid from the wheel space cavity to the
bucket shank cavity with the plurality of protrusions to minimize
pressure loss in the cooling fluid.
18. The method of claim 17, further comprising positioning the
plurality of protrusions at an interface between the wheel space
cavity and the bucket shank cavity.
19. The method of claim 18, further comprising spacing the
plurality of protrusions apart circumferentially on the rotor
assembly about the interface between the wheel space cavity and the
bucket shank cavity.
20. The method of claim 17, further comprising discharging the
cooling fluid into a hot gas path through at least one cooling
passage in fluid communication with the bucket shank cavity.
Description
FIELD OF THE DISCLOSURE
[0001] Embodiments of the disclosure relate generally to gas
turbine engines and more particularly to systems and methods for
facilitating onboarding of bucket purging and cooling flows.
BACKGROUND OF THE DISCLOSURE
[0002] Gas turbines are widely used in industrial and commercial
operations. A typical gas turbine includes a compressor at the
front, one or more combustors around the middle, and a turbine at
the rear. The compressor imparts kinetic energy to the working
fluid (e.g., air) to produce a compressed working fluid at a highly
energized state. The compressed working fluid exits the compressor
and flows to the combustors where it mixes with fuel and ignites to
generate combustion gases having a high temperature and pressure.
The hot combustion gases flow to the turbine where they expand to
produce work. Consequently, the turbine is exposed to very high
temperatures due to the hot combustion gases. As a result, the
various turbine components, such as the turbine buckets, typically
need to be cooled. In some instances, a portion of the compressed
air may be diverted from the compressor to one or more components
of the gas turbine engine for cooling purposes. The diverted air
may be divided into any number of cooling flows or circuits. As the
cooling flows pass through the gas turbine engine, they may
experience pressure drops, which may decrease efficiency.
Accordingly, there is a need to provide improved cooling systems
and methods that eliminate or reduce pressure losses in the cooling
flows.
BRIEF DESCRIPTION OF THE DISCLOSURE
[0003] Some or all of the above needs and/or problems may be
addressed by certain embodiments of the disclosure. According to
one embodiment, there is disclosed a turbine system for
facilitating onboarding of a cooling fluid. The system may include
a rotor assembly, a wheel space cavity adjacent to the rotor
assembly, and a bucket shank cavity in fluid communication with the
wheel space cavity. The system may also include at least one
protrusion disposed on the rotor assembly in the wheel space
cavity. The at least one protrusion may be configured to direct the
cooling fluid radially from the wheel space cavity to the bucket
shank cavity to minimize pressure loss in the cooling fluid.
[0004] According to another embodiment, there is disclosed a
turbine system for facilitating smooth onboarding of a cooling
fluid. The system may include a rotor assembly and a number of
buckets attached to the rotor assembly. Each of the buckets may
include a bucket shank cavity therein. The system may also include
a wheel space cavity adjacent to the rotor assembly. The bucket
shank cavity may be in fluid communication with the wheel space
cavity. The system may also include a number of protrusions
disposed on the rotor assembly in the wheel space cavity. The
protrusions may be configured to direct the cooling fluid radially
from the wheel space cavity to the bucket shank cavities.
[0005] Further, according to another embodiment, there is disclosed
a method for facilitating onboarding of a cooling fluid. The method
may include positioning a bucket shank cavity in fluid
communication with a wheel space cavity. The method may also
include positioning a number of protrusions on a rotor assembly in
the wheel space cavity. Moreover, the method may include directing
the cooling fluid radially from the wheel space cavity to the
bucket shank cavity with the protrusions.
[0006] Other embodiments, aspects, and features of the invention
will become apparent to those skilled in the art from the following
detailed description, the accompanying drawings, and the appended
claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] Reference will now be made to the accompanying drawings,
which are not necessarily drawn to scale.
[0008] FIG. 1 is an example schematic view of a gas turbine engine,
according to an embodiment of the disclosure.
[0009] FIG. 2 is an example schematic cross-sectional view of a gas
turbine assembly, according to an embodiment of the disclosure.
[0010] FIG. 3 is an example schematic perspective view of a portion
of a gas turbine rotor assembly, according to an embodiment of the
disclosure.
[0011] FIG. 4 is an example schematic perspective view of a portion
of a gas turbine rotor assembly, according to an embodiment of the
disclosure.
DETAILED DESCRIPTION OF THE DISCLOSURE
[0012] Illustrative embodiments will now be described more fully
hereinafter with reference to the accompanying drawings, in which
some, but not all embodiments are shown. The disclosure may be
embodied in many different forms and should not be construed as
limited to the embodiments set forth herein. Like numbers refer to
like elements throughout.
[0013] Illustrative embodiments are directed to, among other
things, systems and methods for facilitating smooth onboarding of a
cooling fluid to one or more turbine buckets. For example, in
certain embodiments, a turbine system may include a rotor assembly.
A number of buckets may be circumferentially attached to the rotor
assembly so as to from a turbine stage, such as, but not limited
to, a first turbine stage. In some instances, each of the buckets
may include a bucket shank cavity therein. The turbine assembly may
also include a wheel space cavity positioned adjacent to the rotor
assembly. The wheel space cavity may be in fluid communication with
the bucket shank cavities. In this manner, a cooling fluid (such as
extracted compressor discharge air) may flow from the wheel space
cavity to the bucket shank cavities.
[0014] In certain embodiments, a number of protrusions may be
disposed on the rotor assembly in the wheel space cavity. For
example, the protrusions may be positioned on the rotor assembly
adjacent to one another at an interface between the wheel space
cavity and the bucket shank cavities. That is, the protrusions may
be spaced apart from one another circumferentially on the rotor
assembly at the interface between the wheel space cavity and the
bucket shank cavity. In one example, the protrusions may include
fins, blocks, pegs, or the like. The protrusions may be any
geometric profile. The protrusions may be configured to direct the
cooling fluid radially from the wheel space cavity to the bucket
shank cavities.
[0015] The protrusions increase the swirl on the flow of cooling
fluid by adding tangential velocity and bringing the cooling fluid
closer to rotor tangential velocity. When there is no differential
movement between the buckets and the nearby cooling fluid, the
cooling fluid smoothly onboards the buckets with limited pressure
loss. That is, the protrusions facilitate lower pressure loss and
enable smooth onboarding of the flow of cooling fluid into the
bucket shank cavities, which increases back flow margin within the
buckets.
[0016] In certain embodiments, each of the buckets may include at
least one cooling passage in communication with the bucket shank
cavity. The cooling passage may be configured to discharge at least
a portion of the cooling fluid into a hot gas path. For example,
the cooling passage may extend through an airfoil portion of the
bucket, which may be disposed within the hot gas path. The airfoil
portion of the bucket may include one or more exit ports or holes
in communication with the cooling passage so that at least a
portion of the cooling fluid may exit the exit ports into the hot
gas path. In order to avoid backflow of the combustion gas in the
hot gas path into the cooling passage, the cooling fluid in the
cooling passage may have a pressure greater than the combustion gas
in the hot gas path.
[0017] Turning now to the drawings, FIG. 1 depicts an example
schematic view of a gas turbine assembly 100 as may be used herein.
The gas turbine assembly 100 may include a gas turbine having a
compressor 102. The compressor 102 may compress an incoming flow of
air 104. The compressor 102 may deliver the compressed flow of air
104 to a combustor 106. The combustor 106 may mix the compressed
flow of air 104 with a pressurized flow of fuel 108 and ignite the
mixture to create a flow of combustion gases 110. Although only a
single combustor 106 is shown, the gas turbine engine may include
any number of combustors 106. The flow of combustion gases 110 may
be delivered to a turbine 112. The flow of combustion gases 110 may
drive the turbine 112 so as to produce mechanical work. The
mechanical work produced in the turbine 112 may drive the
compressor 102 via a shaft 114 and an external load 116, such as an
electrical generator or the like.
[0018] The gas turbine engine may use natural gas, various types of
syngas, and/or other types of fuels. The gas turbine engine may be
any one of a number of different gas turbine engines offered by
General Electric Company of Schenectady, N.Y., including, but not
limited to, those such as a 7 or a 9 series heavy duty gas turbine
engine and the like. The gas turbine engine may have different
configurations and may use other types of components. The gas
turbine engine may be an aeroderivative gas turbine, an industrial
gas turbine, or a reciprocating engine. Other types of gas turbine
engines also may be used herein. Multiple gas turbine engines,
other types of turbines, and other types of power generation
equipment also may be used herein together.
[0019] In certain embodiments, as schematically depicted in FIG. 2,
the turbine 112 of FIG. 1 may include a rotor assembly 202. A
number of buckets 204 may be circumferentially attached to the
rotor assembly 202 so as to from a first turbine stage 206,
although the systems and method described herein may be associated
with any turbine stage. In some instances, each of the buckets 204
may include a bucket shank cavity 208 therein. A wheel space cavity
210 may be formed within or adjacent to the rotor assembly 202. The
wheel space cavity 210 may be in fluid communication with the
bucket shank cavities 208. In this manner, a cooling fluid 212
(such as extracted compressor discharge air from the compressor 102
of FIG. 1) may flow from the wheel space cavity 210 to the bucket
shank cavities 208.
[0020] Still referring to FIG. 2, each of the buckets 204 may
include at least one cooling passage 214 therein. The cooling
passage 214 may be in communication with the bucket shank cavity
208. The cooling passage 214 may be configured to discharge at
least a portion of the cooling fluid 212 into a hot gas path 216.
For example, the cooling passage 214 may extend through an airfoil
portion 218 of the bucket 204. The airfoil portion 218 may at least
partially extend into the hot gas path 216. The airfoil portion 218
may include one or more exit ports or holes 220 in communication
with the cooling passage 214. In this manner, the cooling fluid 212
may flow from the wheel space cavity 210 to the bucket shank
cavities 208, into the cooling passage 214, and out of the exit
ports or holes 220 into the hot gas path 216. In order to avoid
backflow of the combustion gas in the hot gas path 216 into the
cooling passage 214, the cooling fluid 212 in the cooling passage
214 may have a pressure greater than the combustion gas in the hot
gas path 216.
[0021] Due to the rotation of the rotor assembly 202, a large
pressure drop in the cooling fluid 212 may occur at the interface
222 (or junction) between the wheel space cavity 210 and the bucket
shank cavities 208. The pressure drop may decrease the back flow
margin and/or the overall efficiency of the gas turbine engine. In
order to eliminate or minimize the pressure drop in the cooling
fluid 212 between the wheel space cavity 210 and the bucket shank
cavities 208, a number of protrusions 224 may be disposed on the
rotor assembly 202 in the wheel space cavity 210. For example, the
protrusions 224 may be positioned on the rotor assembly 210 at the
interface 222 between the wheel space cavity 210 and the bucket
shank cavities 208. The protrusions 224 may be configured to direct
the cooling fluid 212 radially from the wheel space cavity 210 to
the bucket shank cavities 208. Directing the cooling fluid 212
radially from the wheel space cavity 210 to the bucket shank
cavities 208 may eliminate or reduce the pressure drop of the
cooling fluid 212.
[0022] As schematically depicted in FIGS. 3 and 4, the protrusions
224 may be spaced apart from one another circumferentially on the
rotor assembly 202 at the interface 222 between the wheel space
cavity 210 and the bucket shank cavity 208. In certain embodiments,
the protrusions 224 may include fins, blocks, pegs, or the like.
The protrusions may be any geometric profile that directs the
cooling fluid radially from the wheel space cavity 210 to the
bucket shank cavities 208.
[0023] Although embodiments have been described in language
specific to structural features and/or methodological acts, it is
to be understood that the disclosure is not necessarily limited to
the specific features or acts described. Rather, the specific
features and acts are disclosed as illustrative forms of
implementing the embodiments.
* * * * *