Bleed valve

Patent metadata

Field	Value
Publication number	US-10036273-B2
Application number	US-201514881775-A
Country	US
Kind code	B2
Filing date	Oct 13, 2015
Priority date	Nov 6, 2014
Publication date	Jul 31, 2018
Grant date	Jul 31, 2018

Abstract

A bleed valve for a gas turbine engine, the bleed valve comprising: an inlet coupled to an air source; and an outlet coupled to an air sink. The bleed valve also comprises a first stage of flow area modulation between the inlet and the outlet. Also a second stage of flow area modulation between the first stage and the outlet. The pressure can be equalized between the first and second stages. There is also an arrangement comprising a plurality of bleed valves and a controller to control the flow areas of at least one of the first and second stages of each bleed valve.

First claim

The invention claimed is:

1. A bleed valve for a gas turbine engine, the bleed valve comprising:
an inlet coupled to an air source;
an outlet coupled to an air sink;
a first stage of flow area modulation between the inlet and the outlet;
a second stage of flow area modulation between the first stage and the outlet; and
a controller to control the modulation of the flow area of at least one of the first stage and second stage, wherein the controller is configured to equalise the pressure drop across the first stage and the second stage.

2. A bleed valve as claimed in claim 1 wherein the first stage comprises any of the group comprising: a bi-stable valve that is open or closed; a discretely variable valve that has a plurality of open states; a continuously variable valve; a butterfly valve; a flap valve; a ball valve; a shaped port; one or more louvers.

3. A bleed valve as claimed in claim 1 wherein the second stage comprises any of the group comprising: a bi-stable valve that is open or closed; a discretely variable valve that has a plurality of open states; a continuously variable valve; a shaped port; one or more louvers; a sliding cover; a variable iris; a temperature controlled shape memory alloy variable area structure; a pressure controlled elastically deformable variable area structure.

4. A bleed valve as claimed in claim 1 wherein the controller is configured to control the first stage and the second stage.

5. A bleed valve as claimed in claim 1 wherein the controller is an active controller.

6. A bleed valve as claimed in claim 1 wherein the controller is a passive controller.

7. A bleed valve as claimed in claim 1 wherein the controller is mechanical; electrical; electronic; implemented in software.

8. A bleed valve as claimed in claim 1 wherein the controller is located remotely from the bleed valve.

9. A bleed valve as claimed in claim 1 further comprising a perforate plate between the first stage and the second stage.

10. An arrangement comprising:
a plurality of bleed valves, each as claimed in claim 1 ; and
a controller to control the flow area of at least one of the first and second stages of each bleed valve.

11. An arrangement as claimed in claim 10 wherein the controller is configured to control the flow area of the first and second stages of each bleed valve.

12. An arrangement as claimed in claim 10 wherein the controller is configured to control any number of the plurality of bleed valves to be closed, partially open or fully open.

13. A gas turbine engine comprising an arrangement as claimed in claim 10 .

14. A gas turbine engine comprising a bleed valve as claimed in claim 1 .

15. A gas turbine engine as claimed in claim 14 wherein the air source comprises a compressor stage or a turbine stage.

16. A gas turbine engine as claimed in claim 14 wherein the air sink comprises a turbine stage; a cooling air reservoir; a bypass duct; overboard of the gas turbine engine.

17. A gas turbine engine comprising an array of bleed valves, each bleed valve as claimed in claim 1 .

18. A gas turbine engine as claimed in claim 14 wherein the array is an annular array; an axial array; or an array that is annular and axial.

Assignees

• Rolls Royce Plc

Inventors

• Kozuch Michael Georg
• Hussain Zahid Muhammad
• Britchford Kevin Mark

Classifications

• F01D17/105 Primary

  by passing part of the fluid · CPC title

• F02C9/18

  by bleeding, bypassing or acting on variable working fluid interconnections between turbines or compressors or their stages {(F02C3/113 takes precedence)} · CPC title

• F02K3/075 Primary

  controlling flow ratio between flows · CPC title

• F01D5/02

  Blade-carrying members, e.g. rotors (rotors of non-bladed type F01D1/34; stators F01D9/00 {; selecting particular materials F01D5/28}) · CPC title

• F02C6/08

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