Hydrogen Fuel Nozzle Vanes for Flashback-Resistant Mixing

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Solution Overview

Problem

Turbine engines using hydrocarbon fuels produce environmentally unwanted byproducts such as NOx, CO, UHC, and oxides of sulfur, and the use of hydrogen fuel poses challenges like flashback and flameholding due to its faster burning velocity and wider flammable range.

Innovation Solution

A fuel nozzle assembly with vanes angled to control flame spread, including inward and outer radial sections with varying axial and tangential velocity components, and a conical intermediate wall to accelerate flow and improve mixing, allowing for hydrogen fuel use without diluents.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If hydrogen fuel is used in the combustor, then flame temperature increases and burning velocity increases, but flashback and flameholding risk increases

Engineering Contradiction:
Improveflame temperatureVSAvoidflashback and flameholding risk
Core Design Contradiction:
TemperatureVSReliability

Solution Approach 1:

The patent employs dynamically adjustable fuel nozzle assemblies with movable vanes that can change their angular position to control fuel spray patterns and mixing characteristics. This dynamic adjustment allows the system to adapt to varying operating conditions, optimizing combustion stability while preventing flashback and flameholding even at high flame temperatures characteristic of hydrogen combustion.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The invention changes key combustion parameters by controlling fuel-air mixing ratios, spray angles, and flow velocities through adjustable nozzle components. By varying these parameters in real-time, the system maintains reliable combustion of hydrogen fuel without allowing flashback or excessive flameholding, thus resolving the contradiction between high flame temperature and combustion safety.

Inventive Principle:
Principle #35Parameter changes

2Adaptability or versatility

If hydrogen fuel is used in the combustor, then wider flammable range is achieved, but flashback and flameholding occur more easily

Engineering Contradiction:
Improveflammable rangeVSAvoidflashback and flameholding susceptibility
Core Design Contradiction:
Adaptability or versatilityVSReliability

Solution Approach 1:

The adjustable vane mechanism enables dynamic control of fuel spray trajectories and mixing zone characteristics, allowing the combustor to adapt to the wider flammable range of hydrogen while maintaining combustion stability boundaries that prevent flashback and flameholding across varying operating conditions.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

By changing mixing parameters, spray angles, and flow distribution through the adjustable nozzle assembly, the system exploits hydrogen's wide flammable range for improved adaptability while simultaneously controlling combustion parameters to prevent flashback and flameholding, thus resolving the contradiction between versatility and reliability.

Inventive Principle:
Principle #35Parameter changes

3Ease of operation

If traditional hydrocarbon fuels are used in the combustor, then easier combustion is achieved, but environmentally unwanted byproducts are produced

Engineering Contradiction:
Improvecombustion easeVSAvoidNOx, CO, UHC, and sulfur oxide emissions
Core Design Contradiction:
Ease of operationVSObject-generated harmful factors

Solution Approach 1:

The patent changes the fundamental combustion parameter from hydrocarbon fuel to hydrogen fuel, which eliminates carbon-containing emissions such as CO, UHC, and sulfur oxides. The adjustable fuel nozzle assembly compensates for hydrogen's different combustion characteristics, maintaining ease of combustion operation while achieving clean emission profiles free of traditional hydrocarbon pollutants.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The invention converts hydrogen's typically problematic fast burning velocity and wide flammable range (which cause flashback and flameholding) into benefits through precise control mechanisms. By using adjustable vanes to control mixing and spray patterns, the system harnesses hydrogen's high flame temperature and reactivity for efficient combustion while preventing harmful flashback and flameholding, thus turning potential harms into benefits.

Inventive Principle:
Principle #22Blessing in disguise (Convert harm into benefit)

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

Reduces NOx emissions and minimizes flashback and flameholding, enabling efficient combustion of hydrogen fuel with improved mixing and control of flame spread.

Implementation Method 1

a conical intermediate wall to accelerate flow and improve mixing

Methodology Applied
Scientific EffectFlow acceleration through conical geometry: Venturi Effect

Implementation Method 2

vanes angled to control flame spread, including inward and outer radial sections with varying axial and tangential velocity components

Methodology Applied
Scientific EffectTurbulent mixing: Turbulence

Implementation Method 3

Hydrogen or hydrogen mixed with another element has a higher flame temperature than traditional hydrocarbon fuels

Methodology Applied
Scientific EffectCombustion: Combustion

Data Source

PatentEP4667825A1Gas turbine engine and fuel nozzle assembly therefor
Publication Date: 2025.12.24 GENERAL ELECTRIC CO
  • EP4667825A1 patent drawingFigure 1
  • EP4667825A1 patent drawingFigure 2
  • EP4667825A1 patent drawingFigure 3

AI summary

A gas turbine engine (10), comprising: a compressor section (12), a combustion section (14), and a turbine section (16) in serial flow arrangement, with the combustion section (14) comprising: a combustor (30) liner that at least partially defines a combustion chamber (50); and a gaseous fuel nozzle assembly (48) fluidly coupled with the combustion chamber (50), the gaseous fuel nozzle assembly (48) comprising a fuel-air mixer (100, 200), a gaseous fuel passage (110, 210) fluidly coupled with the fuel-air mixer (100, 200), and an air passage (112, 212) fluidly coupled with the fuel-air mixer (100, 200); wherein the fuel-air mixer (100, 200) includes a plurality of vanes (130, 230, 231); wherein at least one vane of the plurality of vanes (130, 230, 231) is disposed at least partially at an angle (160) relative to an axial direction; and wherein the angle (160) varies in a radial direction.