Axially Staged Micromixer Cap for Gas Turbine Combustion

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current micromixer configurations in industrial gas turbine engines are inflexible, pose mechanical challenges, and require complex fuel nozzle connections, limiting control over fuel usage and combustion efficiency, while also being costly and inefficient.

Innovation Solution

An axially stacked fuel input configuration with micromixer tubes that receive compressed air from an air plenum, allowing fuel to enter from a radial direction and mix with air before entering the combustion chamber, simplifying the combustion can design and enhancing mixing efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If conventional micromixer configurations are used, then fuel mixing with air is achieved, but the configuration is restricted to conform to rounded combustion can shape and requires complex fuel nozzle connections

Engineering Contradiction:
Improvemicromixer configuration flexibilityVSAvoidfuel nozzle connection complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The micromixer assembly is segmented into multiple axially-staged fuel inputs with separate micromixer tubes for each stage. Each stage can be independently configured and connected to fuel nozzles, allowing modular assembly that reduces overall connection complexity while maintaining configuration flexibility. The segmentation allows each fuel stage to be optimized independently rather than conforming to a single rounded shape constraint.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The invention transitions from a conventional single-plane micromixer configuration to an axially-staged three-dimensional arrangement. Fuel inputs are distributed across multiple axial stages, with micromixer tubes extending vertically through the assembly. This dimensional change allows the micromixer to adapt to various combustion can shapes and reduces the need for complex radial connections by utilizing axial stacking.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Productivity

If conventional micromixer configurations are used, then combustion is achieved, but control over fuel usage and combustion efficiency is limited

Engineering Contradiction:
Improvecombustion efficiencyVSAvoidfuel input configuration complexity
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The fuel input system is divided into multiple axially-staged inputs, each with its own micromixer tubes. This segmentation enables independent control of fuel delivery at different stages, improving combustion efficiency through staged combustion while keeping each individual stage's configuration relatively simple and manageable.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The axially-staged configuration enables dynamic control of fuel distribution across different vertical levels. Each fuel stage can be independently adjusted to optimize combustion at different positions, allowing the system to adapt to varying operational conditions and improve overall combustion efficiency without requiring overly complex static configurations.

Inventive Principle:
Principle #15Dynamics

3Ease of manufacture

If conventional micromixer configurations are used, then fuel and air mixing is achieved, but the configuration is costly and inefficient

Engineering Contradiction:
Improvemanufacturing costVSAvoidfuel-air mixing efficiency
Core Design Contradiction:
Ease of manufactureVSProductivity

Solution Approach 1:

The micromixer assembly uses segmented axially-staged fuel inputs with standardized micromixer tube components. This segmentation allows for modular manufacturing where identical or similar components can be produced in batches, reducing per-unit manufacturing costs while maintaining efficient fuel-air mixing performance across multiple stages.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The axially-staged micromixer configuration uses universal micromixer tube designs that can serve multiple fuel stages. These multi-functional components perform both mixing and structural support functions across different stages, reducing the need for specialized expensive components and simplifying manufacturing while maintaining mixing efficiency.

Inventive Principle:
Principle #6Universality (Multi-functionality)

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 configuration provides a more efficient and flexible mixing of fuel and air, ensuring thorough mixing prior to combustion, reducing mechanical complexity, and allowing for optimized dynamics and emissions while maintaining traditional effusion cooling, potentially lowering costs.

Implementation Method 1

Fuel enters each of the fuel stages from a radial direction of the combustion can, from an inlet on a radially outer periphery of the fuel stages, and the fuel surrounds the micromixer tubes that extends through the fuel stages

Methodology Applied
Scientific EffectTurbulent mixing: Turbulence

Implementation Method 2

maintaining traditional effusion cooling of the micromixer cap to limit durability risks

Methodology Applied
Scientific EffectEffusion cooling: Effusion

Data Source

PatentEP3147568B1Axially staged micromixer cap and method for using the same
Publication Date: 2022.02.23 GENERAL ELECTRIC CO
  • EP3147568B1 patent drawingFigure 1
  • EP3147568B1 patent drawingFigure 2
  • EP3147568B1 patent drawingFigure 3

AI summary

A method of providing fuel to a combustion chamber 101 of a combustion can 10 in a radial direction of the combustion can 10, and a micromixer cap 210 having axially arranged fuel stages that receive fuel from a radial direction, the fuel stages supplies fuel to different radial zones of micromixer tubes 210 arranged in a concentric configuration to provide a mixture of fuel and air for combustion.