Partial Direct Injectors for Hydrogen Combustion Flashback Prevention
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional gas turbine combustors struggle to efficiently burn high levels of hydrogen or pure hydrogen without causing flashback or flame holding conditions, which can damage the fuel injectors.
Innovation Solution
A fuel injection assembly is designed for gas turbine combustors, featuring a fuel injector coupled to an outer sleeve, a boss coupled to a combustion liner, and an insert with a mixing channel and partial direct injectors. This assembly allows for the delivery of hydrogen and air to a secondary combustion zone without causing flashback or flame holding issues.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-generated harmful factors
If traditional combustion systems burn high levels of hydrogen or pure hydrogen, then CO2 emissions are significantly reduced or eliminated, but flashback or flame holding conditions occur that can cause severe damage to the injector
Solution Approach 1:
The fuel injection system is divided into multiple injectors with different functions: a primary fuel injector for natural gas and a secondary AFS fuel injector for hydrogen. This segmentation allows each injector to be optimized for its specific fuel type, preventing flashback damage while enabling hydrogen combustion.
Solution Approach 2:
A cross-flow of air is introduced as an intermediary between the primary and secondary combustion zones. This cross-flow acts as a barrier that prevents the hydrogen flame from propagating back into the hydrogen supply, eliminating flashback conditions while allowing efficient hydrogen burning.
2Adaptability or versatility
If traditional AFS fuel injectors are used with high hydrogen content fuels, then hydrogen combustion is achieved, but flame holding conditions occur that migrate the combustion flame towards the fuel supply
Solution Approach 1:
The secondary AFS fuel injector is designed with specific local characteristics including a particular geometry and positioning that creates a localized combustion environment suitable for hydrogen. The injector delivers fuel and air in a cross-flow pattern that maintains stable combustion without flame holding, adapting the local flow conditions to match hydrogen's combustion properties.
3Object-generated harmful factors
If a fuel injection assembly delivers hydrogen and air to a secondary combustion zone, then CO2 emissions are reduced, but the system complexity increases with additional injectors and control mechanisms
Solution Approach 1:
The fuel injection assembly is designed with multi-functionality to handle both natural gas and hydrogen combustion requirements. The primary fuel injector can operate with natural gas while the secondary AFS fuel injector handles hydrogen supplementation, allowing the system to adapt to different fuel scenarios without requiring entirely separate systems.
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
The fuel injection assembly effectively delivers hydrogen and air to the secondary combustion zone, preventing flashback and flame holding, thus ensuring the safe and efficient operation of gas turbine combustors when burning high hydrogen content fuels.
Implementation Method 1
The fuel injection assembly effectively delivers hydrogen and air to the secondary combustion zone, preventing flashback and flame holding
Data Source
AI summary
A fuel injection assembly for a combustor of a gas turbine includes a fuel injector configured to couple to an outer sleeve of the combustor. A boss is configured to couple to a combustion liner of the combustor at a position axially and circumferentially aligned with the fuel injector. An insert is removably coupled to the boss. The insert includes a flange portion and an annular wall portion extending from the flange portion and defining a mixing channel. The insert defines a plurality of partial direct injectors spaced apart from one another and disposed about the mixing channel. A combustor including such a fuel injection assembly is also provided.