Integrated Metering Valve Spool Shutoff Mechanism
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing fuel supply systems for gas turbine engines require multiple components, including a metering valve, pressure regulating valve, and shutoff valve, which increase complexity and potential for leakage, while the shutoff valve is necessary to prevent fuel flow when not needed.
Innovation Solution
A fuel supply system integrates a metering valve with a movable spool and extension/retraction chambers, communicating with a servo valve to control fuel flow, eliminating the need for a separate shutoff valve by sealing the forward face of the spool against the housing to block flow when not required, thus directly controlling fuel delivery to the combustor.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a separate shutoff valve is included in the fuel supply system, then fuel flow can be completely blocked when not needed, but the system complexity and potential for leakage increase
Solution Approach 1:
The patent combines the shutoff function and metering function into a single integrated valve assembly. The metering valve spool has a forward face that can seal against a seal in the housing to block fuel flow, eliminating the need for a separate shutoff valve. This merging reduces the number of components, potential leakage points, and system complexity while maintaining reliable fuel flow control.
Solution Approach 2:
The metering valve spool is designed to perform multiple functions: it controls fuel metering through its position and simultaneously provides shutoff capability through the sealing action of its forward face against the seal. This multi-functionality allows a single component to replace what would traditionally require multiple separate valves, reducing system complexity while maintaining operational reliability.
2Measurement precision
If multiple valves (metering valve, pressure regulating valve, shutoff valve) are used, then precise fuel control is achieved, but the number of leakage points and system complexity increase
Solution Approach 1:
By integrating the shutoff and metering functions into one valve assembly, the patent reduces the total number of valves from three to two (eliminating the separate shutoff valve). This reduction directly decreases the number of potential leakage points while preserving precise fuel volume control through the metering valve spool's positioning and sealing capabilities.
3Device complexity
If a separate shutoff valve is eliminated, then system complexity is reduced, but the ability to block fuel flow must be maintained through the metering valve
Solution Approach 1:
The metering valve spool is designed with dual functionality: it meters fuel flow through its position control and provides complete shutoff capability through the sealing action of its forward face against the seal in the housing. This multi-functionality allows the single metering valve to replace the traditional three-valve configuration, reducing complexity while maintaining reliable fuel flow blocking capability.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This integrated system simplifies the fuel supply by eliminating the need for a separate shutoff valve, reducing leakage and complexity, while ensuring accurate fuel delivery and pressure regulation to the combustor, enhancing operational efficiency and reliability.
Implementation Method 1
The extension and retraction chambers communicate with a servo valve to communicate a pressure fluid and a dump connection to one of the extension and retraction chambers to extend or retract the metering valve spool
Implementation Method 2
Downstream of the metering valve the fuel passes through an in-line pressure regulating valve which maintains a desired fuel pressure drop across the metering valve window
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A metering valve spool (112) controls a volume of fuel passing through a metering valve (104). The spool (112) has a forward face. A line from a pump has a connection into a chamber. The face of the metering valve spool (112) may contact a seal (116) to block flow into the chamber. The metering valve (104) is connected to a pressure regulating valve. The pressure regulating valve is to be connected to a combustor. A control selectively moves the metering valve spool (112) to control a volume of fuel delivered from the chamber to the pressure regulating valve. The control is also programmed to move the metering valve spool (112) to a position where a forward face of the metering valve spool (112) seals on the seal (116) to block flow from the pump from reaching the pressure regulating valve, and also from reaching the tap. A gas turbine engine is also disclosed.