Translating gaspath bleed valve

Patent metadata

Field	Value
Publication number	US-2016348685-A1
Application number	US-201514721015-A
Country	US
Kind code	A1
Filing date	May 26, 2015
Priority date	May 26, 2015
Publication date	Dec 1, 2016
Grant date	—

Abstract

A bleed of valve comprises a ring axially translatable between a retracted position in which the ring is configured to close an annular bleed off opening defined in a converging portion of a radially outer annular wall of a gas turbine engine gaspath and a deployed position in which the ring protrudes into the gaspath to mechanically scoop out incoming air and water/hail particles.

First claim

1 . A bleed off valve (BOV) for a gas turbine engine having a gaspath bounded by a radially outer annular wall extending about an axis of the gas turbine engine, the radially outer annular wall having a converging portion; the BOV comprising:
a ring axially translatable between a retracted position in which the ring is configured to close an annular bleed off opening defined in the converging portion of the radially outer annular wall and a deployed position in which the ring is configured to protrude into the gaspath; and an actuator operatively connected to the ring to axially translate the ring between the retracted and deployed positions.

2 . The BOV as defined in claim 1 , wherein the ring has a gaspath facing surface and a bleed off opening facing surface, the bleed off opening facing surface configured to direct a radially inwardly converging flow stream in the converging portion of the radially outer annular wall of the gaspath towards the bleed off opening.

3 . The BOV as defined in claim 2 , wherein bleed off opening facing surface defines a ramp extending from a leading edge in a radially inwardly converging direction, the ramp gradually curving away from the radially inwardly converging direction.

4 . The BOV as defined in claim 3 , wherein the ramp curves from the radially inwardly converging direction to a generally radially outward direction.

5 . The BOV as defined in claim 1 , wherein the bleed off opening facing surface extends in a radially inwardly converging direction from a leading edge.

6 . The BOV as defined in claim 1 , wherein in the retracted position, the ring mates with a corresponding annular seal adapted to be mounted to the radially outer annular wall.

7 . The BOV as defined in claim 6 , wherein the ring has a radial sealing surface in sliding engagement with the corresponding annular seal.

8 . The BOV as defined in claim 6 , wherein the annular seal is an axial compression seal.

9 . A gas turbine engine comprising: a compressor having a gaspath bounded by a radially outer annular wall extending about an axis of the engine, the radially outer annular wall having a converging portion; a bleed off valve (BOV) having a ring axially translatable between a retracted position in which the ring closes an annular bleed off opening defined in the converging portion of the radially outer annular wall and a deployed position in which the ring protrudes forwardly into the gaspath; and an actuator operable to axially translate the ring between the retracted and the deployed positions.

10 . The gas turbine engine as defined in claim 9 , wherein in said retracted position, the ring cooperates with the radially outer wall to form a continuous flow boundary surface of the gaspath.

11 . The gas turbine engine as defined in claim 9 , wherein the BOV is disposed in a compressor section downstream of a compressor rotor.

12 . The gas turbine engine as defined in claim 9 , wherein the ring has a gaspath facing surface and bleed off opening facing surface, the bleed off facing surface being configured to redirect an incoming flow through the annular bleed off opening.

13 . The gas turbine engine as defined in claim 12 , wherein bleed off opening facing surface extends in a radially inwardly converging direction from a leading edge of the ring.

14 . The gas turbine engine as defined in claim 13 , wherein the bleed off opening facing surface extends from the radially inwardly converging direction to a generally radially outward direction.

15 . A method of extracting water/hail particles and/or air from a core gaspath of a compressor of a gas turbine engine, the method comprising: displacing a ring from a retracted position in which the ring closes a corresponding annular bleed off opening defined in a converging portion of a radially outer annular wall of the core gaspath to a deployed position in which the ring protrudes axially forwardly into the core gaspath to scoop water/hail particles and/or air out of the core gaspath via the annular bleed off opening.

16 . The method as defined in claim 15 , wherein displacing the ring from the retracted position to the deployed position comprises axially translating the ring in a forward direction away from the radially outer annular wall.

17 . The method as defined in claim 15 , wherein the ring has a gaspath facing surface and a bleed off opening facing surface, and wherein scooping comprises using the bleed off opening facing surface of the ring to deflect an incoming flow out of the core gaspath of the compressor.

18 . The method as defined in claim 17 , wherein deflecting comprises guiding the incoming flow along the bleed off opening facing surface of the ring from a generally radially inward direction to a generally radially outward direction.

19 . The method as defined in claim 15 , further comprising centrifuging incoming water and hail particles upstream of the ring.

20 . The method as defined in claim 19 , wherein centrifuging comprises passing the incoming water and hail particles through a low pressure compressor stage.

Assignees

• Pratt & Whitney Canada

Inventors

• Urac Tibor
• Anand Karan

Classifications

• F04D27/0215 Primary

  Arrangements therefor, e.g. bleed or by-pass valves · CPC title

• F04D27/009

  by bleeding, by passing or recycling fluid · CPC title

• F05D2240/55

  Seals · CPC title

• F02C6/08

  the gas being bled from the gas-turbine compressor · CPC title

• F05D2260/57

  using servos, independent actuators, etc. · CPC title