Aspirating seal assembly and method of assembling

Patent metadata

Field	Value
Publication number	US-9976420-B2
Application number	US-201514807376-A
Country	US
Kind code	B2
Filing date	Jul 23, 2015
Priority date	Jul 23, 2015
Publication date	May 22, 2018
Grant date	May 22, 2018

Abstract

An aspirating seal assembly for use in a turbine engine is provided. The aspirating seal assembly includes a face seal and a rotary component. The face seal includes a first annular seal surface, and the rotary component includes a second annular seal surface positioned adjacent the first annular seal surface and defining a seal interface therebetween. The face seal is configured to discharge a flow of air towards the seal interface. The seal assembly also includes a first seal member extending between the first and second annular seal surfaces such that the flow of air induces a back pressure across the seal interface, and a second seal member positioned radially inward from the first seal member and extending between the first and second annular seal surfaces. A length of the second seal member is selected to increase the back pressure induced across the seal interface.

First claim

What is claimed is:

1. An aspirating seal assembly for use in a turbine engine including a stator assembly and a rotor assembly, said aspirating seal assembly comprising:
a face seal of the stator assembly, said face seal comprising a first annular seal surface and an axially extending bearing face;
a rotary component of the rotor assembly, said rotary component comprising a second annular seal surface positioned adjacent said first annular seal surface and defining a seal interface therebetween, wherein said face seal is configured to discharge a flow of air towards said seal interface, and wherein said face seal further comprises a third annular seal surface defined on opposing sides of the axially extending bearing face;
a fluid return channel extending radially inward from a radially outer most portion of the axially extending bearing face therethrough the face seal;
first seal member extending between said first and second annular seal surfaces such that the flow of air induces a pressure drop across said seal interface; and
a second seal member positioned radially inward from said first seal member and extending between said first and second annular seal surfaces such that the flow of air induces a back pressure across the seal interface, wherein a length of said second seal member is selected to increase the back pressure induced across said seal interface.

2. The assembly in accordance with claim 1 , wherein the length of said second seal member is selected such that a non-uniform pressure distribution is formed across said seal interface.

3. The assembly in accordance with claim 1 , wherein said first and second seal members are oriented relative to said face seal such that the back pressure induced across said seal interface is greater at a radially inner portion of said seal interface than at a radially outer portion of said seal interface.

4. The assembly in accordance with claim 1 further comprising a plurality of apertures defined in said face seal such that a first leakage flow path is defined between said plurality of apertures and said first seal member, and such that a second leakage flow path is defined between said plurality of apertures and said second seal member.

5. The assembly in accordance with claim 4 , wherein said first seal member is positioned radially outward from said plurality of apertures, and said second seal member is positioned radially inward from said plurality of apertures.

6. The assembly in accordance with claim 1 , wherein said first and second seal members are coupled to said rotary component and extend towards said first annular seal surface of said face seal.

7. The assembly in accordance with claim 1 , wherein said first and second seal members comprise at least one of a labyrinth seal or a brush seal.

8. A gas turbine engine comprising:
a stator assembly comprising a face seal that comprises a first annular seal surface and an axially extending bearing face;
a rotor assembly comprising a rotary component that comprises a second annular seal surface positioned adjacent said first annular seal surface and defining a seal interface therebetween, wherein said face seal is configured to discharge a flow of air towards said seal interface, and wherein said face seal further comprises a third annular seal surface defined on opposing sides of the axially extending bearing face;
a fluid return channel extending radially inward from a radially outer most portion of the an axially extending bearing face therethrough the face seal; and
a plurality of seal members positioned between said stator assembly and said rotor assembly, wherein said plurality of seal members comprises:
a first seal member extending between said first and second annular seal surfaces such that the flow of air induces a pressure drop across said seal interface; and
a second seal member positioned radially inward from said first seal member and extending between said first and second annular seal surfaces such that the flow of air induces a back pressure across the seal interface, wherein a length of at least one of said second seal member and said axially extending bearing face is selected to increase the back pressure induced across said seal interface.

9. The gas turbine engine in accordance with claim 8 , wherein the length of said second seal member is selected such that a non-uniform pressure distribution is formed across said seal interface.

10. The gas turbine engine in accordance with claim 8 , wherein said first and second seal members are oriented relative to said face seal such that the back pressure induced across said seal interface is greater at a radially inner portion of said seal interface than at a radially outer portion of said seal interface.

11. The gas turbine engine in accordance with claim 8 further comprising a plurality of apertures defined in said face seal such that a first leakage flow path is defined between said plurality of apertures and said first seal member, and such that a second leakage flow path is defined between said plurality of apertures and said second seal member.

12. The gas turbine engine in accordance with claim 11 , wherein said first seal member is positioned radially outward from said plurality of apertures, and said second seal member is positioned radially inward from said plurality of apertures.

13. The gas turbine engine in accordance with claim 8 , wherein said first and second seal members are coupled to said rotary component and extend towards said first annular seal surface of said face seal.

14. The gas turbine engine in accordance with claim 8 , wherein a portion of the rotary component extends axially along a centerline defining a circumferential seal surface and wherein the second seal member and an additional seal member are coupled to the face seal and extend radially towards the circumferential seal surface.

15. A method of assembling an aspirating seal assembly for use in a turbine engine, said method comprising:
positioning a first annular seal surface of a face seal adjacent to a second annular seal surface of a rotary component such that a seal interface is defined therebetween, wherein the face seal is configured to discharge a flow of air towards the seal interface, the face seal further including an axially extending bearing face;
extending a first seal member between the first and second annular seal surfaces such that the flow of air induces a pressure drop across the seal interface;
positioning a second seal member radially inward from the first seal member; and
extending the second seal member between the first and second annular seal surfaces such that the flow of air induces a back pressure across the seal interface, wherein a length of one of the axially extending bearing face or the second seal member is selected to increase the back pressure induced across the seal interface.

16. The method in accordance with claim 15 , wherein extending the second seal member comprises determining the length of the second seal member such that a non-uniform pressure distribution is formed across the seal interface.

17. The method in accordance with claim 15 further comprising orienting the first and second seal members relative to the face seal such that the back pressure induced across the seal interface is greater at a radially inner portion of the seal interface than at a radially outer portion of the seal interface.

18. The method in accordance with claim 15 further comprising defining a plurality apertures in the face seal such that a first leakage flow path is defined bet

Assignees

• Gen Electric

Inventors

• Tran Quang Tue Nguyen
• Erdmenger Rodrigo Rodriguez
• Potokar Christopher Jon

Classifications

• Y02T50/673

  Cross-Sectional Technologies · mapped topic

• Y02E20/14

  Combined heat and power generation [CHP] · CPC title

• F01D11/025

  Seal clearance control; Floating assembly; Adaptation means to differential thermal dilatations · CPC title

• F01D5/046 Primary

  Heating, heat insulation or cooling means · CPC title

• F01D5/048

  Form or construction · CPC title