Combustor Liner with Movable Dilution Gap

Solution Overview

Problem

Gas turbine engines face challenges in producing high-energy combustion gases while limiting emissions and preventing structural deterioration, often requiring compromises that result in unpredictable effects on emissions, pressure oscillations, and liner damage.

Innovation Solution

A combustor assembly with a first and second liner defining a combustion chamber, where the liners are separated by a longitudinal gap extended circumferentially, allowing for dilution fluid to enter and reduce temperatures, and featuring a moveable interface to regulate the gap and accommodate thermal expansion, thereby reducing NOx emissions and improving durability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If cooling air is introduced to limit damage to combustion section structures, then structural durability is improved, but emissions increase and combustion energy is reduced

Engineering Contradiction:

Improvestructural durabilityVSAvoidemissions

Core Design Contradiction:

ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The combustor liner is divided into multiple segments (first liner segment, second liner segment, third liner segment) with gaps between them, allowing controlled introduction of cooling air at specific locations without compromising overall structural integrity. This segmentation enables localized cooling where needed while maintaining combustion efficiency in other regions.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different portions of the combustor liner receive different amounts of cooling air based on local thermal requirements. The gaps between liner segments allow cooling air to be introduced at specific locations (such as the forward end of the second liner segment) where thermal loads are highest, while other regions maintain better combustion conditions.

Inventive Principle:

Principle #3Local quality

2Reliability

If cooling air is introduced to limit deterioration of combustion section structures, then structural durability is improved, but combustion energy is reduced

Engineering Contradiction:

Improvestructural durabilityVSAvoidcombustion energy

Core Design Contradiction:

ReliabilityVSUse of energy by moving object

Solution Approach 1:

The combustor liner is divided into multiple segments (first liner segment, second liner segment, third liner segment) with gaps between them, allowing controlled introduction of cooling air at specific locations without compromising overall structural integrity. This segmentation enables localized cooling where needed while maintaining combustion efficiency in other regions.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different portions of the combustor liner receive different amounts of cooling air based on local thermal requirements. The gaps between liner segments allow cooling air to be introduced at specific locations (such as the forward end of the second liner segment) where thermal loads are highest, while other regions maintain better combustion conditions.

Inventive Principle:

Principle #3Local quality

3Object-generated harmful factors

If geometries at combustion section are changed to limit emissions, then emissions are reduced, but effects on pressure oscillations and liner damage become unpredictable

Engineering Contradiction:

ImproveemissionsVSAvoidpressure oscillation stability

Core Design Contradiction:

Object-generated harmful factorsVSReliability

Solution Approach 1:

The combustor liner segments are designed with movable interfaces that allow dynamic adjustment of gap sizes between segments. This enables the geometry to adapt to different operating conditions, maintaining effective emissions control while allowing the structure to respond to pressure oscillations and thermal expansion without causing unpredictable effects.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The movable interface between liner segments provides feedback mechanisms where the gap size automatically adjusts based on thermal expansion, pressure differentials, and operational conditions. This feedback allows the system to self-regulate and maintain stable pressure oscillations while controlling emissions.

Inventive Principle:

Principle #23Feedback

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 solution effectively reduces NOx emissions, minimizes temperature gradients, and enhances the durability of the combustor and turbine sections by allowing controlled dilution and thermal management, while also improving vibration response.

Implementation Method 1

allowing for dilution fluid to enter and reduce temperatures

Methodology Applied

Scientific EffectDilution:

Implementation Method 2

featuring a moveable interface to regulate the gap and accommodate thermal expansion

Methodology Applied

Scientific EffectThermal expansion: Thermal Expansion

Data Source

PatentUS11725817B2Combustor assembly with moveable interface dilution opening

Publication Date: 2023.08.15 GENERAL ELECTRIC CO

AI summary

A gas turbine engine and combustor assembly are provided, the combustor assembly including a first liner and a second liner together defining at least in part a combustion chamber, wherein the first liner and the second liner are separated by a gap along the longitudinal direction, and wherein the first liner is forward of the second liner relative to a flow of fluid through the combustion chamber along the longitudinal direction, and wherein the gap is extended along the circumferential direction.