Seal assembly for gas turbine engine

• US 10,689,997 B2
• Filed: 04/17/2018
• Issued: 06/23/2020
• Est. Priority Date: 04/17/2018
• Status: Active Grant

• Current Assignee: Rtx Corporation
• Original Assignee: Raytheon Technologies Corporation d/b/a RTX (Rtx Corporation)
• Inventors: Smiddy, Winston Gregory, Lutjen, Paul M.
• Primary Examiner(s): Hansen, Kenneth J
• Assistant Examiner(s): Gillenwaters, Jackson N
• Application Number:
  US15/955,585
• Publication Number:
  US 20190316480A1
• Time in Patent Office: 798 Days
• 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 25/246 Fastening of diaphragms or stator-rings
• CPC Class Codes: F02C 7/28 Arrangement of seals
• CPC Class Codes: F05D 2220/32 in gas turbines
• CPC Class Codes: F05D 2240/11 Shroud seal segments
• CPC Class Codes: F05D 2260/201 by impingement of a fluid
• CPC Class Codes: F05D 2300/6033 Ceramic matrix composites [CMC]
• CPC Class Codes: Y02T 50/60 Efficient propulsion technologies, e.g. for aircraft

Abstract

A seal assembly for a gas turbine engine according to an example of the present disclosure includes, among other things, a seal that has a seal body having a sealing portion that extends from an engagement portion. The sealing portion has a seal face that extends circumferentially between first and second mate faces. The seal body defines an internal cavity that extends circumferentially between the first and second mate faces, and the engagement portion has an impingement face opposite the seal face that defines a plurality of apertures to the internal cavity. A housing is mounted to the seal such that the impingement face is exposed to define a plenum between the housing and the impingement face. The housing defines a plurality of cooling passages, and each of the plurality of cooling passages define a passage axis that is oriented such that a projection of the passage axis intersects the seal body. A method of sealing is also disclosed.

Claims

1. A seal assembly for a gas turbine engine comprising:

a seal including a seal body having a sealing portion that extends from an engagement portion, the sealing portion including a seal face that extends circumferentially between first and second mate faces, the seal body defining an internal cavity that extends circumferentially between the first and second mate faces, and the engagement portion including an impingement face opposite the seal face that defines a plurality of apertures to the internal cavity, wherein the internal cavity extends from a first opening along the first mate face to a second opening along the second mate face; and

a housing mounted to the seal such that the impingement face is exposed to define a plenum between the housing and the impingement face, the housing defining a plurality of cooling passages, and each of the plurality of cooling passages defining a passage axis that is oriented such that a projection of the passage axis intersects the seal body;

a mounting block including an interface portion extending from a mounting portion, the interface portion abutting the engagement portion along an interface to limit relative movement, and the mounting portion mechanically attached to the housing; and

wherein the projection of the passage axis of at least some of the plurality of cooling passages intersects a respective one of the plurality of aptures that is defined along the interface.

2. The seal assembly as recited in claim 1, wherein the seal is made of a first material including a ceramic material, and the seal has a unitary construction.

3. The seal assembly as recited in claim 1, wherein the projection of the passage axis of at least some of the plurality of cooling passages intersects the impingement face.

4. The seal assembly as recited in claim 3, wherein the projection of the passage axis of other passages of the plurality of cooling passages intersects a respective one of the plurality of apertures at a position circumferentially inward if the interface.

5. The seal assembly as recited in claim 1, wherein the interface portion has a dovetail geometry that extends through the first opening to mate with ramped surfaces of the internal cavity and bound movement of the seal relative to the mounting block.

6. The seal assembly as recited in claim 5, wherein the mounting block is a first mounting block and a second mounting block, and the interface portion of the first mounting block is received in the first opening and the interface portion of the second mounting block received in the second opening to secure the seal to the engine case.

8. The seal assembly as recited in claim 1, wherein the seal is made of a first material including a ceramic material, and the mounting block is made of a second material that is the same as the first material.

9. The seal assembly as recited in claim 1, wherein the seal is a blade outer air seal (BOAS).

14. The seal assembly as recited in claim 4, wherein the seal is made of a first material including a ceramic material, and the seal has a unitary construction.

15. The seal assembly as recited in claim 14, wherein the seal is formed from one or more layers of a ceramic matrix composite layup.

16. The seal assembly as recited in claim 14, wherein a sum of a cross-sectional area of all of the apertures defined in the impingement face, inclusive of the plurality of apertures, is between 10% and 25% of a total surface area of the impingement face.

7. The seal assembly as recited in, wherein the seal is made of a first material including a ceramic material, and the mounting block is made of a second, different material.

10. A gas turbine engine comprising:

an engine case extending along an engine axis;

an array of blades rotatable about the engine axis; and

an array of blade outer air seals distributed about the array of blades to bound a core flow path, wherein each of the seals comprises;

an elongated seal body including a seal face that faces toward the core flow path and an opposed impingement face;

wherein the seal body defines an internal cavity that extends circumferentially between opposed mate faces, and the seal body defines a plurality of apertures to the internal cavity along the impingement face; and

wherein the seal is mounted to the engine case such that the impingement face is exposed;

wherein the engine case defines a plurality of cooling passages spaced apart from the impingement face, and each of the plurality of cooling passages defines a passage axis that is oriented such that a projection of the passage axis intersects the seal body of a respective one of the seals; and

an array of circumferentially spaces apart mounting blocks, wherein the mate faces of adjacent seals of the array of seals are arranged to a plurality of intersegment gaps, each of the mounting blocks is arranged along a respective one of the plurality of intersegment gaps and engages surfaces of the respective internal cavity of the adjacent seals, and each of the mounting blocks is mechanically attached to the engine case to limit movement of the respective adjacent seals relative to the engine case;

wherein the projection of the passage axis of at least some passages of the plurality of cooling passages intersects a respective one of the plurality of apertures; and

wherein the projection of the passage axis of one or more of the plurality of cooling passages intersects a respective one of the plurality of apertures that is defined along an interface between a respective mounting block of the array of mounting blocks and the seal body.

11. The gas turbine engine as recited in claim 10, wherein:

the projection of the passage axis of other passages of the plurality of cooling passages intersects the impingement face.

17. The gas turbine engine as recited in claim 10, wherein the internal cavity extends from a first opening along one of the mate faces to a second opening along another one of the mate faces.

18. The gas turbine engine as recited in claim 17, wherein:

each mounting block of the array of mounting includes an interface portion extending from a mounting portion, the interface portion abutting the seal body of a respective one of the blade outer air seals along the interface to limit relative movement, and the mounting portion is mechanically attached to the engine case; and

the interface portion has a dovetail geometry that extends through one of the first and second openings to mate with ramped surfaces of the internal cavity and bound movement of the respective blade outer air seals relative to the mounting block.

12. A method of sealing of a gas turbine engine, comprising:

securing a mounting block to an engine static structure such that the mounting block is positioned along an intersegment gap between mate faces of adjacent blade outer air seals;

wherein each of the adjacent blade outer air seals comprises;

an elongated seal body including a seal face that faces toward a gas path and an opposed impingement face; and

wherein the seal body defines an internal cavity that extends circumferentially between opposed mate faces and defines a plurality of apertures to the internal cavity along the impingement face;

wherein the engine static structure defines a plurality of cooling passages, and each of the plurality of cooling passages defines a passage axis that is oriented such that a projection of the passage axis intersects the seal body of a respective one of the adjacent seals; and

ejecting cooling flow from the plurality of cooling passages such that the cooling flow impinges on surfaces of the seal body;

wherein the projection of the passage axis of at least some passages of the plurality of cooling passages intersects a respective one of the plurality of apertures; and

wherein the projection of the passage axis of one or more of the plurality of cooling passages intersects a respective one of the plurality of apertures that is defined along an interface between the mounting bock and the seal body.

13. The method as recited in claim 12, wherein the projection of the passage axis of at least some passages of the plurality of cooling passages intersects the impingement face.