MICROCHANNEL EXHAUST FOR COOLING AND/OR PURGING GAS TURBINE SEGMENT GAPS

• US 20150118033A1
• Filed: 10/28/2013
• Published: 04/30/2015
• Est. Priority Date: 10/28/2013
• Status: Active Grant

• Current Assignee: GE Infrastructure Technology, LLC (General Electric Company)
• Original Assignee: General Electric Company
• Inventors: WEBER, David Wayne, SMITH, Aaron Ezekiel
• Granted Patent: US 9,518,478 B2
• Time in Patent Office: Days
• US Class Current: 415/175
• CPC Class Codes: F01D 11/003 by packing rings; Mechanical seals
• CPC Class Codes: F01D 11/005 Sealing means between non relatively rotating elements
• CPC Class Codes: F01D 11/008 by spacer elements between the blades, e.g. independent interblade platforms
• CPC Class Codes: F01D 25/12 Cooling
• CPC Class Codes: F01D 9/04 forming ring or sector
• CPC Class Codes: F05D 2240/11 Shroud seal segments
• CPC Class Codes: F05D 2240/57 Leaf seals

Abstract

A gas turbine stator component includes a composite, segmented ring made up of an annular array of arcuate segments, each having end faces formed with respective seal slots, with radial gaps formed between opposed end faces of adjacent arcuate segments. A seal is located between each pair of opposed seal slots to thereby seal the gaps, and a channel is provided in each of said arcuate segments adapted to be supplied with cooling air, the channel connecting to a passage extending between the channel and a respective one of the seal slots or radial gaps, on a lower-pressure side of the seal.

Claims

1. A segment for a ring-shaped, rotary machine stator component comprising:

a segment body having an end face formed with a circumferentially-facing seal slot adapted to receive a seal extending between said segment body and a corresponding seal slot in an adjacent segment body;

a channel provided in said segment body in proximity to said seal slot, supplied with cooling air; and

a passage extending from said channel into said seal slot.

2. The segment of claim 1 wherein said channel communicates with a cooling air inlet duct adapted to supply cooling air from a cooling air source.

3. The segment of claim 1 wherein said passage opens on a radially inner surface of said seal slot.

4. The segment of claim 1 wherein said channel comprises a microchannel having width and/or depth dimensions of between about 50 microns and about 4 mm.

5. The segment of claim 4 wherein said microchannel has a cross-sectional shape selected from round, semi-circular, square, rectangular, triangular or rhomboidal.

6. The segment of claim 5 wherein said passage opens on a radially inner surface of said seal slot.

7. The segment of claim 1 wherein said segment body has an arcuate shape.

8. The segment of claim 4 wherein a hot-gas-facing side of said microchannel is closed by a coating.

9. The segment of claim 8 wherein said coating comprises a thermal barrier coating.

11. The annular turbine component of claim 6 wherein said plural arcuate segments combine to form an annular turbine stator nozzle shroud.

12. The annular turbine component of claim 6 wherein said plural arcuate segments combine to form an annular turbine stator bucket shroud.

19. The gas turbine component of claim 12 wherein said first annular shroud comprises a stator nozzle shroud.

10. An annular turbine component comprising:

plural arcuate segments arranged to form a complete annular ring, each segment having end faces provided with seal slots;

a seal extending between seal slots of adjacent segments sealing radially oriented gaps between the segments;

a channel provided in each segment in proximity to at least one of said seal slots, and adapted to be supplied with cooling air; and

a passage extending from said channel and opening into said at least one seal slot or a respective, radially-oriented gap on a radially-inner, low-pressure side of the seal.

13. The segment of claim 10 wherein said channel comprises a microchannel having width and/or depth dimensions of between about 50 microns and about 4 mm.

14. The segment of claim 13 wherein said microchannel has a cross-sectional shape selected from round, semi-circular, square, rectangular, triangular or romboidal.

15. The segment of claim 10 wherein a radially-inner side of said microchannel is closed by a coating.

17. The gas turbine stator component of claim 15 wherein said passage opens on one of said end faces at a location closer to the seal than to the hot gas path.

18. The gas turbine stator of claim 15 wherein a hot-gas-facing side of said channel is closed by a coating.

20. The gas turbine component of claim 15 wherein said second annular shroud comprises a stator bucket shroud.

16. A gas turbine stator comprising:

first and second axially adjacent, annular shrouds having opposed end faces provided with respective seal slots;

wherein a circumferential, axially-extending gap is formed between said opposed end faces;

a circumferential seal seated in said respective seal slots to thereby seal said axially-extending gap, said seal, in use, separating relatively higher and lower pressure areas on radially-outer and radially-inner sides thereof, said radially-inner side exposed to a hot gas path; and

one or more cooling channels provided within each of said first and second axially-adjacent, annular shrouds adapted to be supplied with cooling air, said one or more cooling channels arranged to introduce cooling air into a respective one of said seal slots or axially-extending gaps in the relatively lower pressure area on said radially-inner side of said seal.