Rotor seal segment

• US 8,246,299 B2
• Filed: 02/04/2008
• Issued: 08/21/2012
• Est. Priority Date: 02/28/2007
• Status: Active Grant

• Current Assignee: Rolls-Royce PLC (Rolls-Royce Holdings Plc)
• Original Assignee: Rolls-Royce PLC (Rolls-Royce Holdings Plc)
• Inventors: Razzell, Anthony G., Hillier, Steven M.
• Primary Examiner(s): Nguyen, Ninh H
• Application Number:
  US12/068,181
• Publication Number:
  US 20080206046A1
• Time in Patent Office: 1,660 Days
• Field of Search: 415/173.1, 415/116, 415/213.1
• US Class Current: 415/173.1
• CPC Class Codes: F01D 11/005 Sealing means between non relatively rotating elements
• CPC Class Codes: F01D 11/08 for sealing space between rotor blade tips and stator specially-shaped blade tips therefor F01D5/20
• CPC Class Codes: F01D 11/24 by selectively cooling-heating stator or rotor components
• CPC Class Codes: F01D 25/14 Casings modified therefor double casings F01D25/26
• CPC Class Codes: F01D 9/04 forming ring or sector
• CPC Class Codes: F05D 2240/11 Shroud seal segments
• CPC Class Codes: F05D 2260/201 by impingement of a fluid
• CPC Class Codes: F05D 2260/205 Cooling fluid recirculation, i.e. after cooling one or more components is the cooling fluid recovered and used elsewhere for other purposes
• CPC Class Codes: F05D 2300/21 Oxide ceramics
• CPC Class Codes: F05D 2300/6033 Ceramic matrix composites [CMC]

Abstract

A ceramic seal segment for a shroud ring of a rotor of a gas turbine engine, the ceramic seal segment positioned radially adjacent the rotor and characterized by being a hollow section that defines an inlet and an outlet for the passage of coolant therethrough.

Claims

1. A ceramic seal segment for a shroud ring of a rotor of a gas turbine engine, the ceramic seal segment positioned radially adjacent the rotor, the ceramic seal segment being a box section with a hollow interior that defines an inlet and an outlet for passage of coolant therethrough.

2. A ceramic seal segment as claimed in claim 1 wherein an impingement plate is provided within the hollow section seal segment, the impingement plate defining an array of holes through which the coolant passes and thereby creates a plurality of coolant jets that impinge on a radially inner surface or a radially inner wall of the seal segment.

3. A ceramic seal segment as claimed in claim 2 wherein the impingement plate or device comprises a ceramic material.

4. A ceramic seal segment as claimed in claim 2 wherein the impingement plate or device is metallic.

5. An array of ceramic seal segments as claimed in claim 1 wherein the outlet is an axial gap between segments.

6. An array of ceramic seal segments as claimed in claim 1 wherein the seal segments are held in position via a mounting sleeve and the mounting sleeve is hollow and allows cooling fluid to flow between adjacent ceramic seal segments.

7. A ceramic seal segment for a shroud ring of a rotor of a gas turbine engine, the ceramic seal segment positioned radially adjacent the rotor and characterised by being a hollow section that defines an inlet and an outlet for the passage of coolant therethrough,

wherein a cascade impingement device is provided within the hollow section seal segment, the cascade impingement device defining a plurality of chambers in flow sequence, each chamber having an array of holes through which the coolant passes and thereby creates a plurality of coolant jets that impinge on a radially inner surface or a radially inner wall of the seal segment.

8. A ceramic seal segment as claimed in claim 7 wherein the coolant flows through the chambers generally in a downstream direction with respect to a general flow of gas products through the engine.

9. A ceramic seal segment as claimed in claim 7 wherein an impingement plate is provided within the hollow section seal segment, the impingement plate defining an array of holes through which the coolant passes and thereby creates a plurality of coolant jets that impinge on a radially inner surface or a radially inner wall of the seal segment.

10. A ceramic seal segment as claimed in claim 9 wherein the impingement plate or device comprises a ceramic material.

11. A ceramic seal segment as claimed in claim 9 wherein the impingement plate or device is metallic.

12. A ceramic seal segment for a shroud ring of a rotor of a gas turbine engine, the ceramic seal segment positioned radially adjacent the rotor and characterised by being a hollow section that defines an inlet and an outlet for the passage of coolant therethrough,

wherein the seal segment is held in position via a mounting sleeve, which is mounted to a cassette via fasteners.

13. A ceramic seal segment as claimed in claim 12 wherein the mounting sleeve comprises a ceramic matrix composite material.

14. A ceramic seal segment as claimed in claim 12 wherein the cassette is a metallic material.

15. A ceramic seal segment as claimed in claim 12 wherein an impingement plate is provided within the hollow section seal segment, the impingement plate defining an array of holes through which the coolant passes and thereby creates a plurality of coolant jets that impinge on a radially inner surface or a radially inner wall of the seal segment.

16. A ceramic seal segment as claimed in claim 15 wherein the impingement plate or device comprises a ceramic material.

17. A ceramic seal segment as claimed in claim 15 wherein the impingement plate or device is metallic.

18. An array of ceramic seal segments as claimed in claim 12 wherein the mounting sleeve has a radially inward surface and grooves are defined in the surface.

19. An array of ceramic seal segments as claimed in claim 18 wherein the mounting sleeve is a ceramic matrix composite material.

20. An array of ceramic seal segments as claimed in claim 18 wherein the outlet is an axial gap between segments and air is ejected through the axial gap via the grooves.