Systems and Methods for Reducing or Limiting One or More Flows Between a Hot Gas Path and a Wheel Space of a Turbine

Abstract

A turbine assembly is disclosed herein. The turbine assembly may include a rotor with at least one bucket extending radially therefrom. The turbine assembly also may include a stator assembly positioned adjacent to the at least one bucket. Moreover, the turbine assembly may include a seal assembly. The seal assembly may include a first flange extending in a substantially axial direction from the at least one bucket. The seal assembly also may include a second flange extending from the stator assembly in the substantially axial direction opposite the first flange. The second flange may include at least one protuberance projecting towards the first flange.

Description

FIELD

Embodiments of the disclosure relate generally to gas turbine engines and more particularly relate to systems and methods for reducing or limiting one or more flows between a hot gas path and a wheel space of a turbine.

BACKGROUND

A gas turbine engine typically includes a compressor, a combustor, and a turbine. The efficiency of the turbine depends in part on the amount of cooling air flow from the compressor that is used to cool components in the hot gas path in the turbine section. The cooling air flow may be introduced into the wheel space of the turbine to limit high-temperature gases from entering into the wheel space. Excess ingestion flow of the hot gasses into the wheel space may increase the wheel space temperature beyond material capabilities, resulting in materials potentially exceeding temperature limits, which may contribute to rotor creep and/or rupture. On the other hand, excess cooling air and/or purge flow to the wheel space to prevent hot gas ingestion may decrease turbine efficiency since the cooling air flow may not be available to the entire turbine for work production.

BRIEF DESCRIPTION

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 assembly. The turbine assembly may include a rotor with at least one bucket extending radially therefrom. The turbine assembly also may include a stator assembly having at least one stationary nozzle vane positioned adjacent to the at least one bucket. Moreover, the turbine assembly may include a seal assembly. The seal assembly may include a first flange extending from the at least one bucket in a substantially axial direction. The seal assembly also may include a second flange extending from the stator assembly in a substantially axial direction opposite the first flange. The second flange may include at least one protuberance projecting towards the first flange.

According to another embodiment, there is disclosed a turbine system. The system may include a compressor. The system also may include a combustion system in communication with the compressor. Moreover, the system may include a turbine in communication with the combustion system. The turbine may include a rotor having at least one bucket extending radially therefrom. The turbine also may include a stator assembly having at least one stationary nozzle vane positioned adjacent to the at least one bucket. Further, the turbine may include a seal assembly. The seal assembly may include a first flange extending from the at least one bucket in a substantially axial direction. The seal assembly also may include a second flange extending from the stator assembly in a substantially axial direction opposite the first flange. The second flange may include at least one protuberance projecting towards the first flange.

Further, according to another embodiment, there is disclosed a method to reduce or limit a flow to a wheel space and a hot gas path of a turbine. The method may include positioning a first flange about at least one bucket extending radially from a rotor. Moreover, the method may include positioning a second flange about a stator assembly positioned adjacent to the at least one bucket. The first flange and the second flange may be radially spaced apart to at least partially form a seal assembly. Further, the method may include reducing the flow to the wheel space and the hot gas path of the turbine with at least one protuberance projecting from the second flange towards the first flange.

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

Reference will now be made to the accompanying drawings, which are not necessarily drawn to scale.

FIG. 1 schematically depicts an example view of a gas turbine engine assembly, according to an embodiment of the disclosure.

FIG. 2 schematically depicts an example view of a portion of a turbine assembly, according to an embodiment of the disclosure.

FIG. 3 schematically depicts an example view of a seal assembly within a turbine assembly, according to an embodiment of the disclosure.

FIG. 4 schematically depicts an example view of a seal assembly within a turbine assembly, according to an embodiment of the disclosure.

FIG. 5 schematically depicts an example view of a seal assembly within a turbine assembly, according to an embodiment of the disclosure.

DETAILED DESCRIPTION

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.

FIG. 1 shows a schematic view of gas turbine engine 10 as may be used herein. The gas turbine engine 10 may include a compressor 15. The compressor 15 compresses an incoming flow of air 20. The compressor delivers the compressed flow of air 20 to a combustor 25. The combustor 25 mixes the compressed flow of air 20 with a compressed flow of fuel 30 and ignites the mixture to create a flow of combustion gases 35. Although only a single combustor 25 is shown, the gas turbine engine 10 may include any number of combustors 25. The flow of combustion gases 35 is in turn delivered to a downstream turbine 40. The flow of combustion gases 35 drives the turbine 40 to produce mechanical work. The mechanical work produced in the turbine 40 drives the compressor 15 via a shaft 45 and an external load 50, such as an electrical generator or the like.

The gas turbine engine 10 may use natural gas, various types of syngas, and/or other types of fuels. The gas turbine engine 10 may be anyone of a number of different gas turbine engines such as those offered by General Electric Company of Schenectady, N.Y. and the like. The gas turbine engine 10 may have different configurations and may use other types of components. 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.

FIG. 2 schematically depicts one example embodiment of a portion of the turbine 40. The turbine 40 may include a rotor 52 positioned about a longitudinal axis. A number of buckets 54 may be mounted to the rotor 52. For example, the buckets 54 may be circumferentially spaced apart from one another and extend radially outward from the rotor 52. The buckets 54 may form one or more stages in the turbine 40. The buckets 54 may include a shank portion 56 and an airfoil portion 58.

A stationary outer casing 60 may be disposed about the buckets 54 to define a hot gas passage through the turbine 40 for the flow of combustion gases 35. In addition, a number of stator assemblies 62 may be positioned adjacent to the buckets 54. For example, the stator assemblies 62 may be positioned upstream and/or downstream of each bucket 54. Each of the stator assemblies 62 may include a stationary nozzle vane 64. A wheel space 66 may be formed between each stator assembly 62 and bucket 54.

A seal assembly 68 may be positioned between each stator assembly 62 and bucket 54. The seal assembly 68 may prevent, reduced, and/or limit the flow of combustion gases 35 from entering the wheel space 66. Further, the seal assembly 68 may reduce the amount of purge air and/or cooling air needed to limit hot gases from entering the wheel space 66.

The seal assembly 68 may include a first flange 70 extending from the bucket 54 in a substantially axial direction. In some instances, the first flange 70 may be an angel wing seal. The first flange 70 may extend axially from the upstream and/or downstream surfaces of the shank portion 56 of the bucket 54. In some instances, the first flange 70 may terminate at a radially outwardly extending tip 72, which may include teeth or fins. In other instances, the radially outwardly extending tip 72 may be omitted.

The seal assembly also may include a second flange 74 extending from the stator assembly 62 in a substantially axial direction opposite the first flange 70. In some instances, the second flange 74 may be a discourager seal. Any number of discourager seals may be used herein. The second flange 74 may extend axially from the upstream and/or downstream surfaces of the stator assembly 62. In some instances, the second flange 74 may be positioned radially outward of the first flange 70. For example, the second flange 74 may be radially spaced apart from the first flange 70 so as to form a gap therebetween. Other components and other configurations may be used herein.

FIG. 3 depicts an example embodiment of a seal assembly 100 as may be used herein. The seal assembly 100 may include a first flange 102 extending from the shank portion 56 of the bucket 54. In some instances, the first flange 102 may be an angel wing seal. For example, the first flange 102 may terminate at a radially outwardly extending tip 104. In other instances, the radially outwardly extending tip 104 may be omitted. The seal assembly 100 also may include a second flange 106 extending from the stator assembly 62. In some instances, the second flange 106 may be a discourager seal. The second flange 106 may include at least one protuberance 108 projecting towards the first flange 102. In some instances, the at least one protuberance 108 may be disposed about a distal end 110 of the second flange 106. The at least one protuberance 108 may include a number of protuberances projecting towards the first flange 102. The at least one protuberance 108 may be a tooth, wing, nub, fin, or combination thereof. Other components and other configurations may be used herein. The at least one protuberance 108 and the first flange 102 may cooperate to define a more tortuous path for cooling flow to go through and limit hot gas ingest into the wheel space. In some instances, the second flange 106 may be inserted into the stator assembly 62. In other instances, the second flange 106 can be caulked in, welded on, or form an integral part of the stator assembly 62.

FIG. 4 depicts an example embodiment of a seal assembly 112 as may be used herein. The seal assembly 112 may include a first flange 114 extending from the shank portion 56 of the bucket 54. In some instances, the first flange 114 may be an angel wing seal. For example, the first flange 114 may terminate at a radially outwardly extending tip 116. In other instances, the radially outwardly extending tip 116 may be omitted. The seal assembly 112 also may include a second flange 118 extending from the stator assembly 62. In some instances, the second flange 118 may be a discourager seal. The second flange 118 may include at least one protuberance 120 projecting towards the first flange 114. The at least one protuberance 120 may include a number of protuberances projecting towards the first flange 114. In some instances, the at least one protuberance 120 may be disposed between a distal end 122 of the second flange 118 and the stator assembly 62. The at least one protuberance 120 may be a tooth, wing, nub, fin, or combination thereof. Other components and other configurations may be used herein. The at least one protuberance 120 and the first flange 114 may cooperate to define a more tortuous path for cooling flow to go through and limit hot gas ingest into the wheel space. In some instances, the second flange 118 may be inserted into the stator assembly 62. In other instances, the second flange 118 can be caulked in, welded on, or form an integral part of the stator assembly 62.

FIG. 5 depicts an example embodiment of a seal assembly 124 as may be used herein. The seal assembly 124 may include a first flange 126 extending from the shank portion 56 of the bucket 54. In some instances, the first flange 126 may be an angel wing seal. For example, the first flange 126 may terminate at a radially outwardly extending tip 128. In other instances, the radially outwardly extending tip 128 may be omitted. The seal assembly 124 also may include a second flange 130 extending from the stator assembly 62. In some instances, the second flange 130 may be a discourager seal. The second flange 130 may include at least one protuberance 132 projecting from a distal end 134 of the second flange 130. In some instances, the at least one protuberance 132 may include two protuberances extending in opposite directions. For example, in an embodiment, the second flange 130 and the at least one protuberance 132 may collectively form a T-shaped member. In other instances, the at least one protuberance 132 may extend in an axial direction opposite the first flange 126. The at least one protuberance 132 may include a number of protuberances. The at least one protuberance 132 may be a tooth, wing, nub, fin, or combination thereof Other components and other configurations may be used herein. The at least one protuberance 132 and the first flange 126 may cooperate to define a more tortuous path for cooling flow to go through and limit hot gas ingest into the wheel space. In some instances, the second flange 130 may be inserted into the stator assembly 62. In other instances, the second flange 130 can be caulked in, welded on, or form an integral part of the stator assembly 62

The protuberances extending from the second flange may prevent, reduced, and/or limit the flow of combustion gases 35 from entering the wheel space 66. Further, the protuberances extending from the second flange may prevent, reduced, and/or limit purge air and/or cooling air from entering the hot gas passage. The second flange may include multiple protuberances projecting in various directions. For example, the second flange may include one or more protuberances disposed about the distal end of the second flange, one or more protuberances disposed between the distal end of the second flange and the stator assembly, one or more protuberances projecting from the distal end of the second flange in the axial direction opposite the first flange, and/or a combination thereof.

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. For example, the various embodiments described in FIGS. 1-5 may be combined. That is, the second flange may include multiple protuberances projecting in various directions.

Claims

1. A turbine assembly, comprising:

a rotor;

at least one bucket extending radially from the rotor;

a stator assembly positioned adjacent to the at least one bucket; and

a seal assembly, comprising: a first flange extending from the at least one bucket in a substantially axial direction; and a second flange extending from the stator assembly in a substantially axial direction opposite the first flange, wherein the second flange comprises at least one protuberance projecting towards the first flange.

2. The turbine assembly of claim 1, wherein the at least one protuberance is disposed about a distal end of the second flange.

3. The turbine assembly of claim 1, wherein the at least one protuberance is disposed between a distal end of the second flange and the stator assembly.

4. The turbine assembly of claim 1, further comprising a second at least one protuberance projecting from the distal end of the second flange in the substantially axial direction opposite the first flange.

5. The turbine assembly of claim 1, wherein the second flange comprises a discourager seal.

6. The turbine assembly of claim 1, wherein the first flange comprises an angle wing seal.

7. The turbine assembly of claim 1, wherein the first flange and the second flange define a gap therebetween.

8. The turbine assembly of claim 1, wherein the at least one protuberance comprises one or more teeth, wings, nubs, or fins.

9. A turbine system, comprising:

a compressor;

a combustion system in communication with the compressor;

a turbine in communication with the combustion system, wherein the turbine comprises: a rotor; at least one bucket extending radially from the rotor; a stator assembly positioned adjacent to the at least one bucket; and a seal assembly, comprising: a first flange extending from the at least one bucket in a substantially axial direction; and a second flange extending from the stator assembly in a substantially axial direction opposite the first flange, wherein the second flange comprises at least one protuberance projecting towards the first flange.

10. The system of claim 9, wherein the at least one protuberance is disposed about a distal end of the second flange.

11. The system of claim 9, wherein the at least one protuberance is disposed between a distal end of the second flange and the stator assembly.

12. The system of claim 9, further comprising a second at least one protuberance projecting from the distal end of the second flange in the substantially axial direction opposite the first flange.

13. The system of claim 9, wherein the second flange comprises a discourager seal.

14. The system of claim 9, wherein the first flange comprises an angle wing seal.

15. The system of claim 9, wherein the first flange and the second flange define a gap therebetween.

16. The system of claim 9, wherein the at least one protuberance comprises one or more teeth, wings, nubs, or fins.

17. A method to reduce or limit a flow to a wheel space and a hot gas path of a turbine, the method comprising:

positioning a first flange about at least one bucket extending radially from a rotor;

positioning a second flange about a stator assembly positioned adjacent to the at least one bucket, wherein the first flange and the second flange are radially spaced apart to at least partially form a seal assembly; and

reducing the flow to the wheel space and the hot gas path of the turbine with at least one protuberance projecting from the second flange towards the first flange.

18. The method of claim 17, further comprising disposing the at least one protuberance about a distal end of the second flange.

19. The method of claim 17, further comprising disposing the at least one protuberance between a distal end of the second flange and the stator assembly.

20. The method of claim 17, further comprising reducing the flow to the wheel space and the hot gas path of the turbine with a second at least one protuberance projecting from the distal end of the second flange in the substantially axial direction opposite the first flange.