Fuel control system with shutoff feature

Patent metadata

Field	Value
Publication number	US-2016305338-A1
Application number	US-201514685971-A
Country	US
Kind code	A1
Filing date	Apr 14, 2015
Priority date	Apr 14, 2015
Publication date	Oct 20, 2016
Grant date	—

Abstract

A fuel control system according to an exemplary aspect of the present disclosure includes, among other things, a fuel delivery valve selectively moveable to a closed position to shut off a flow of fuel to a downstream location. The system further includes a windmill bypass valve, and a shutoff pressure line between the windmill bypass valve and the fuel delivery valve. The windmill bypass valve is selectively operable to direct fuel to the shutoff pressure line to assist the movement of the fuel delivery valve to the closed position. A method is also disclosed.

First claim

1 . A fuel control system, comprising:
a fuel delivery valve selectively moveable to a closed position to shut off a flow of fuel to a downstream location; a windmill bypass valve; and a shutoff pressure line between the windmill bypass valve and the fuel delivery valve, the windmill bypass valve selectively operable to direct fuel to the shutoff pressure line to assist the movement of the fuel delivery valve to the closed position.

2 . The system as recited in claim 1 , wherein:
the fuel delivery valve is a minimum pressure shutoff valve (MPSOV); the windmill bypass valve is selectively operable to direct fuel to a low pressure line; and a first outlet of the windmill bypass valve fluidly coupled to the shutoff pressure line is vertically spaced-apart from a second outlet of the windmill bypass valve fluidly coupled to the low pressure line.

3 . The system as recited in claim 1 , further comprising a valve and a control unit configured to selectively provide instructions to the valve to open and close the windmill bypass valve.

4 . The system as recited in claim 1 , wherein, when the windmill bypass valve is in the open position, the shutoff pressure line is fluidly coupled to a spring chamber of the fuel delivery valve only when the fuel delivery valve is in an open position.

5 . The system as recited in claim 4 , wherein:
the fuel delivery valve includes an annulus in an outer housing thereof; a piston within the fuel delivery valve includes an orifice; and when the fuel delivery valve is in the open position, the annulus and the orifice align such that fuel from the shutoff pressure line is allowed to enter the spring chamber.

6 . The system as recited in claim 5 , wherein, when the fuel delivery valve is in the closed position, the annulus and the orifice are not aligned such that fuel from the shutoff pressure line is prevented from entering the spring chamber.

7 . The system as recited in claim 5 , wherein the shutoff pressure line is fluidly coupled to an annulus surrounding the outer housing, and wherein fuel is communicated into the spring chamber through the annulus.

8 . The system as recited in claim 1 , further comprising:
a metering valve; a shutdown line fluidly coupled to a spring chamber of the windmill bypass valve; and an electromechanical valve operable to adjust a pressure in the shutdown line to move the windmill bypass valve between the open position and the closed position.

9 . The system as recited in claim 1 , wherein the downstream location is a combustor section of a gas turbine engine.

10 . A method, comprising:
directing a flow of fuel along a main fuel line from an upstream location toward a downstream location; and shutting off the flow of fuel within the main fuel line to the downstream location by directing a portion of the flow of fuel from a windmill bypass valve to a fuel delivery valve to assist movement of the fuel delivery valve to a closed position.

11 . The method as recited in claim 10 , wherein the portion of the flow of fuel enters a spring chamber of the fuel delivery valve only when the fuel delivery valve is in an open position.

12 . The method as recited in claim 11 , wherein:
the fuel delivery valve includes an annulus in an outer housing thereof; a piston within the fuel delivery valve includes an orifice; and when the fuel delivery valve is in the open position, the annulus and the orifice align such that fuel is allowed to enter the spring chamber.

13 . The method as recited in claim 12 , wherein, when the fuel delivery valve is in the closed position, the annulus and the orifice are not aligned such that fuel is prevented from entering the spring chamber.

14 . The method as recited in claim 10 , further comprising:
selectively opening and closing the windmill bypass valve by adjusting a pressure in a shutdown line fluidly coupled to a spring chamber of the windmill bypass valve.

15 . The method as recited in claim 10 , wherein:
the fuel delivery valve is a minimum pressure shutoff valve (MPSOV); the windmill bypass valve is selectively operable to direct fuel to a low pressure line; and a first outlet of the windmill bypass valve fluidly coupled to the shutoff pressure line is vertically spaced-apart from a second outlet of the windmill bypass valve fluidly coupled to the low pressure line.

Assignees

• Hamilton Sundstrand Corp

Inventors

• Chapski David L

Classifications

• F02C7/262

  Restarting after flame-out · CPC title

• F05D2270/64

  Hydraulic actuators · CPC title

• F02C9/46

  Emergency fuel control · CPC title

• F05D2270/092

  in particular blow-out and relight · CPC title

• F05D2260/606

  Bypassing the fluid · CPC title