Pressure regulated piston seal for a gas turbine combustor liner

Patent metadata

Field	Value
Publication number	US-11221140-B2
Application number	US-202016907013-A
Country	US
Kind code	B2
Filing date	Jun 19, 2020
Priority date	Apr 21, 2017
Publication date	Jan 11, 2022
Grant date	Jan 11, 2022

Abstract

A seal assembly to seal a gas turbine hot gas path flow at an interface of a combustor liner and a downstream component, such as a stage one turbine nozzle, in a gas turbine. The seal assembly including a piston ring seal housing, defining a cavity, and a piston ring disposed within the cavity. The piston ring disposed circumferentially about the combustor liner. The piston ring is responsive to a regulated pressure to secure sealing engagement of the piston ring and outer surface of the combustor liner. The seal assembly includes at least one of one or more sectional through-slots, bumps or channel features to provide for a flow therethrough of a high-pressure (P high ) bypass airflow exiting a compressor to the cavity. The high-pressure (P high ) bypass airflow exerting a radial force on the piston ring.

First claim

What is claimed is:

1. A seal assembly to seal a gas turbine hot gas path flow at an interface of a combustor liner and a downstream component in a gas turbine, the seal assembly comprising:
a piston ring seal housing having defined therein a cavity; and
a piston ring disposed within the cavity of the piston ring seal housing and circumferentially about the combustor liner, the piston ring responsive to a regulated pressure to secure sealing engagement of the piston ring and an outer surface of the combustor liner, the piston ring including at least one arcuate seal ring segment,
wherein at least one of the piston ring and the piston ring seal housing comprises one or more features, one of extending into or protruding from, at least one of an upstream surface of the piston ring and a front wall surface of the piston ring seal housing, to define a gap between the upstream surface of the piston ring and the front wall surface of the piston ring seal housing to guide a flow therethrough of a high-pressure (P high ) bypass airflow exiting an upstream component and exert a radial force on an outermost radial surface of the piston ring in a direction perpendicular to a main gas flow, wherein the gap is configured to extend without interruption from radially outward of the upstream surface of the piston ring into and open at an end of the piston ring seal housing to enable airflow to pass therethrough regardless of an angular position of the piston ring.

2. The seal assembly as claimed in claim 1 , wherein the downstream component is a stage one turbine nozzle.

3. The seal assembly as claimed in claim 1 , wherein one of the piston ring seal housing or the piston ring is rotated relative to an other of the piston ring seal housing or the piston ring.

4. The seal assembly as claimed in claim 1 , wherein the gap comprises one or more channels extending into a front wall to define a conduit to guide the flow therethrough of the high-pressure (P high ) bypass airflow exiting the upstream component.

5. A gas turbine comprising:
a combustor liner;
a stage one nozzle disposed downstream of the combustor liner;
a piston seal assembly defined at an interface of the combustor liner and the stage one nozzle to seal a gas turbine hot gas path flow, the piston seal assembly comprising:
a piston ring seal housing having defined therein a cavity; and
a piston ring disposed within the cavity of the piston ring seal housing and circumferentially about the combustor liner, the piston ring responsive to a regulated pressure to secure sealing engagement of the piston ring and an outer surface of the combustor liner, the piston ring including at least one arcuate seal ring segment,
wherein at least one of the piston ring and the piston ring seal housing comprises one or more features, one of extending into or protruding from, at least one of an upstream surface of the piston ring and a front wall surface of the piston ring seal housing, to define a gap between the upstream surface of the piston ring and the front wall surface of the piston ring seal housing to guide a flow therethrough of a high-pressure (P high ) bypass airflow exiting an upstream component and exert a radial force on an outermost radial surface of the piston ring in a direction perpendicular to a main gas flow, wherein the gap is configured to extend without interruption from radially outward of the upstream surface of the piston ring into and open at an end of the piston ring seal housing to enable airflow to pass therethrough regardless of an angular position of the piston ring.

6. The gas turbine as claimed in claim 5 , wherein one of the piston ring seal housing or the piston ring is rotated relative to an other of the piston ring seal housing or the piston ring during a takeoff condition.

7. A gas turbine as claimed in claim 5 , wherein the gap comprises one or more channels extending into a front wall to channel the flow therethrough of the high-pressure (P high ) bypass airflow exiting the upstream component to the cavity and wherein the high-pressure (P high ) bypass airflow exerts the radial force on the piston ring.

8. A gas turbine system comprising:
a compressor section;
a combustor section coupled to the compressor section, the combustor section comprising an annular combustor liner defining an annular combustion chamber coaxial with a longitudinal axis;
a turbine section coupled to the combustor section, the turbine section comprising a stage one turbine nozzle positioned at a downstream end of the annular combustor liner;
a piston seal assembly defined at an interface of the annular combustor liner and the stage one turbine nozzle to seal a gas turbine hot gas path flow, the piston seal assembly comprising:
a piston ring seal housing having defined therein a cavity; and
a piston ring disposed within the cavity of the piston ring seal housing and circumferentially about the annular combustor liner, the piston ring responsive to a regulated pressure to secure sealing engagement of the piston ring and an outer surface of the annular combustor liner, the piston ring including at least one arcuate seal ring segment,
wherein at least one of the piston ring and the piston ring seal housing comprise one or more features, one of extending into or protruding from, at least one of an upstream surface of the piston ring and a front wall surface of the piston ring seal housing, to define a gap between the upstream surface of the piston ring and the front wall surface of the piston ring seal housing to guide a flow therethrough of a high-pressure (P high ) bypass airflow exiting an upstream component and exert a radial force on an outermost radial surface of the piston ring in a direction perpendicular to a main gas flow, wherein the gap is configured to extend without interruption from radially outward of the upstream surface of the piston ring into and open at an end of the piston ring seal housing to enable airflow to pass therethrough regardless of an angular position of the piston ring.

9. The gas turbine system as claimed in claim 8 , wherein one of the piston ring seal housing or the piston ring is rotated relative to an other of the piston ring seal housing or the piston ring during a takeoff condition.

10. The gas turbine system as claimed in claim 8 , wherein the gap comprises one or more channels extending into at least one of the upstream surface of the piston ring and the front wall of the piston ring seal housing to channel the flow therethrough of the high-pressure (P high ) bypass airflow exiting the compressor section to the cavity and wherein the high-pressure (P high ) bypass airflow exerts the radial force on the piston ring.

Assignees

• Gen Electric

Inventors

• Shi Jinjie
• Schadewald Stephen Gerard
• Hoppa Jason Paul
• Gallier Kirk Douglas
• Wolfe Christopher Edward
• Proctor Robert

Classifications

• F23R3/60

  Support structures; Attaching or mounting means · CPC title

• F01D9/023

  Transition ducts between combustor cans and first stage of the turbine in gas-turbine engines; their cooling or sealings · CPC title

• F23R3/002 Primary

  Wall structures (F23R3/02 and F23R3/007 take precedence) · CPC title

• F23R2900/00012

  Details of sealing devices · CPC title

• F05D2300/6033

  Ceramic matrix composites [CMC] · CPC title