Gas Turbine Engine Systems Involving Hydrostatic Face Seals with Anti-Fouling Provisioning

• US 20090047124A1
• Filed: 08/17/2007
• Published: 02/19/2009
• Est. Priority Date: 08/17/2007
• Status: Active Grant

• Current Assignee: Rtx Corporation
• Original Assignee: United Technologies Corporation (Raytheon Technologies Corporation d/b/a RTX)
• Inventors: Glahn, Jorn A., Munsell, Peter M.
• Granted Patent: US 8,109,716 B2
• Time in Patent Office: Days
• US Class Current: 415/174.500
• CPC Class Codes: F01D 11/025 Seal clearance control; Floating assembly; Adaptation means to differential thermal dilatations
• CPC Class Codes: F01D 11/04 using sealing fluid, e.g. steam
• CPC Class Codes: F05D 2300/224 Carbon, e.g. graphite
• CPC Class Codes: F16J 15/342 with means for feeding fluid directly to the face

Abstract

Gas turbine engine systems involving hydrostatic face seals with anti-fouling provisioning are provided. In this regard, a representative turbine assembly for a gas turbine engine comprises: a turbine having a hydrostatic seal; the hydrostatic seal having a seal face, a seal runner, a carrier, and a biasing member; the seal face and the seal runner defining a high-pressure side and a lower-pressure side of the seal; the carrier being operative to position the seal face relative to the seal runner; and the biasing member being located on the lower-pressure side of the seal and being operative to bias the carrier such that interaction of the biasing member and gas pressure across the seal causes the carrier to position the seal face relative to the seal runner.

Claims

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

a face seal having a seal face;

a seal runner; and

means for reducing a potential for debris to foul the hydrostatic seal formed by the seal face and the seal runner.

2. The seal of claim 1, wherein:

the seal face and the seal runner define a high-pressure side and a lower-pressure side of the seal;

the seal further comprises a biasing member operative to bias the seal face toward the seal runner; and

the means for reducing a potential for debris to foul the hydrostatic seal comprises the biasing member being located on the lower-pressure side of the seal.

3. The seal of claim 2, wherein the biasing member comprises a spring.

4. The seal of claim 1, wherein:

the seal comprises a stator assembly; and

the seal face is mounted to the stator assembly.

5. The seal of claim 1, wherein:

the seal comprises a rotor assembly; and

the seal runner is mounted to the rotor assembly.

6. The seal of claim 1, wherein:

the seal face and the seal runner define a high-pressure side and a lower-pressure side of the seal;

the face seal has an air bearing supply channel extending from the high-pressure side to a side on which the seal face is located.

7. The seal of claim 6, wherein the means for reducing a potential for debris to foul the hydrostatic seal comprises the air bearing supply channel exhibiting a straight configuration.

8. The seal of claim 7, wherein the air bearing supply channel exhibits a non-uniform diameter along a length thereof.

9. The seal of claim 6, wherein:

the seal further comprises a carrier, the face seal being mounted to the carrier such that the carrier positions the seal face with respect to the seal runner; and

the means for reducing a potential for debris to foul the hydrostatic seal comprises a shield operative to form a physical barrier that discourages debris travelling on a radially inward trajectory from entering the air bearing supply channel.

10. The seal of claim 9, wherein:

the carrier has an orifice aligned with the air bearing supply channel; and

the shield is attached to the carrier adjacent the orifice.

11. A turbine assembly for a gas turbine engine comprising:

a turbine having a hydrostatic seal;

the hydrostatic seal having a seal face, a seal runner, a carrier, and a biasing member;

the seal face and the seal runner defining a high-pressure side and a lower-pressure side of the seal;

the carrier being operative to position the seal face relative to the seal runner; and

the biasing member being located on the lower-pressure side of the seal and being operative to bias the carrier such that interaction of the biasing member and gas pressure across the seal causes the carrier to position the seal face relative to the seal runner.

12. The assembly of claim 11, wherein:

the seal face is a surface of a face seal, the face seal having an air bearing supply channel extending from the high-pressure side to a side on which the seal face is located; and

the seal further comprises a shield extending outwardly from the carrier on the high-pressure side of the seal, the shield being operative to discourage debris from entering the air bearing supply channel.

13. The assembly of claim 12, wherein the air bearing supply channel exhibits a straight configuration.

14. The assembly of claim 11, wherein the turbine is a low-pressure turbine.

15. The assembly of claim 11, wherein the hydrostatic seal is provided by a stator assembly and a rotor assembly, at least one of which is removably mountable within the turbine.

16. The assembly of claim 11, wherein the hydrostatic seal is a lift-off seal, with the seal face being biased to a contact position in which the seal face contacts the seal runner.

17. A gas turbine engine comprising:

a compressor;

a shaft interconnected with the compressor; and

a turbine operative to drive the shaft, the turbine having a hydrostatic seal;

the hydrostatic seal having a seal face, a seal runner and a biasing member;

the seal face and the seal runner defining a high-pressure side and a lower-pressure side of the seal;

the biasing member being located on the lower-pressure side of the seal and being operative to bias positioning of the seal face relative to the seal runner.

18. The engine of claim 17, wherein at least a portion of the seal face configured to contact the seal runner is formed of a material comprising carbon.

19. The engine of claim 17, wherein the engine is a turbofan.

20. The engine of claim 17, wherein the turbine is a low-pressure turbine.