Dual Fuel-Injector Combustor Layout for Aircraft Flame-Out Relight
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Gas turbine engines, particularly aero engines, face challenges in resisting flame-out and efficiently relighting, especially with fuels like gaseous hydrogen, due to issues such as fuel starvation, compressor stall, and altitude, with existing lighting and relighting systems being unreliable.
Innovation Solution
An aircraft engine system with an annular array of primary and secondary fuel-injectors, each emitting fuel in specific directions, and a controller that manages fuel supply to these injectors based on engine status and maneuvering signals to enhance lighting, relighting, and flame-out resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a single type of fuel-injector is used in the combustion apparatus, then the device complexity is reduced, but the reliability and ability to prevent flame-out deteriorates
Solution Approach 1:
The combustion apparatus is segmented into multiple zones with different fuel-injector types (primary and secondary) arranged in alternating annular arrays. Each zone can be independently controlled to optimize fuel delivery for specific operational conditions, thereby improving flame-out resistance without requiring a complete system redesign.
Solution Approach 2:
Different regions of the combustion apparatus are assigned different fuel-injector configurations tailored to their specific functional requirements. Primary fuel-injectors are positioned in certain annular regions while secondary fuel-injectors are placed in others, allowing each region to have the optimal fuel delivery characteristics for its location and operational role.
2Reliability
If fuel is supplied only to primary fuel-injectors during normal operation, then the fuel system complexity is reduced, but the ability to rapidly relight after flame-out deteriorates
Solution Approach 1:
Secondary fuel-injectors are pre-positioned and pre-configured in the combustion apparatus, ready to be activated immediately upon detecting a flame-out condition. This preliminary arrangement eliminates the need for complex real-time fuel system reconfiguration, allowing rapid relighting by simply activating the pre-positioned secondary injectors.
Solution Approach 2:
The fuel system incorporates feedback mechanisms that continuously monitor combustion status and automatically switch between primary and secondary fuel-injectors based on real-time conditions. When flame-out is detected, the feedback system triggers secondary fuel-injectors to restore combustion, providing automatic and reliable relighting capability.
3Productivity
If fuel is emitted only in the axial direction from fuel-injectors, then the fuel system structure is simplified, but the fuel transport efficiency between adjacent combustor sections deteriorates
Solution Approach 1:
Fuel emission is extended from a single axial dimension to multiple dimensions by introducing radial and azimuthal components. Fuel-injectors emit fuel not only axially but also radially and azimuthally, creating a three-dimensional fuel distribution pattern that enhances transport efficiency between adjacent combustor sections while maintaining manageable system complexity through structured injectors arrangement.
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
Improves lighting, relighting speed and reliability, and enhances flame-out resistance, particularly with hydrogen fuel, by optimizing fuel distribution and emission directions in the engine system.
Implementation Method 1
insufficient fuel transport between adjacent combustor sections
Implementation Method 2
fuel transport between injectors
Data Source
AI summary
An aircraft includes an engine system which includes a gas turbine engine and a fuel system. The engine has combustion apparatus having an annular array of alternating primary and secondary fuel-injectors. The fuel system includes a fuel store and a controller. The controller is arranged to receive one or more signals indicative of one or more of (i) starting of the gas turbine engine; (ii) flame-out of the combustion apparatus; and (ii) a manoeuvring of the aircraft associated with a risk of flame-out of the combustion apparatus or preparation for such manoeuvring; and in response thereto to control the fuel system to commence supply of fuel from the fuel store to the secondary fuel-injectors of the combustion apparatus. Compared to known aircraft, engine lighting and relighting are achieved for more rapidly and reliably and the aircraft is less susceptible to flame-out, especially where hydrogen fuel is used.