Consumable Support Structures for Additive Manufactured Combustor Shells

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Additive manufacturing of combustor components in gas turbine engines results in support structures that add mass and disrupt flow patterns, reducing engine efficiency and performance due to their complex geometries and overhanging portions.

Innovation Solution

The use of consumable support structures with specific angular orientations and thin thicknesses, designed to vaporize at high temperatures, which are integrated into the injector ports of the combustor shell, allowing for efficient removal during operation and minimizing mass impact on the engine.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If support structures are used to enable additive manufacturing of complex geometries, then manufacturing capability is improved, but mass and flow disruption increase reducing engine efficiency

Engineering Contradiction:
Improvemanufacturing capabilityVSAvoidengine efficiency
Core Design Contradiction:
Ease of manufactureVSLoss of energy

Solution Approach 1:

The support structures are designed as consumable temporary features that are intentionally left in the additive manufacturing process to enable complex geometries, then deliberately removed through controlled erosion during engine operation. They serve their manufacturing purpose and are discarded when no longer needed, eliminating the need for permanent support structures that would continuously degrade performance.

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

Solution Approach 2:

The support structures are designed with specific material properties and geometric parameters (thickness, orientation, composition) that cause them to erode at controlled rates under combustion conditions. By adjusting these parameters, the support structures transition from providing structural support during manufacturing to being easily removable during operation, resolving the contradiction between manufacturing capability and operational efficiency.

Inventive Principle:
Principle #35Parameter changes

2Shape

If support structures are used to create overhanging portions, then geometric complexity is improved, but flow patterns are disrupted

Engineering Contradiction:
Improvegeometric complexityVSAvoidflow disruption
Core Design Contradiction:
ShapeVSObject-generated harmful factors

Solution Approach 1:

The support structures are pre-positioned and pre-shaped during additive manufacturing to provide the necessary geometric complexity and overhanging portions. Their temporary presence enables the creation of complex fuel injector port geometries that would be impossible to manufacture otherwise, while their designed erosion characteristics ensure they do not persist to cause ongoing flow disruption.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The potential harm of support structures causing flow disruption is converted into a benefit by designing them to erode controllably. The erosion process itself becomes useful by clearing the flow paths automatically during engine operation, transforming the harmful presence of support structures into a self-cleaning mechanism that improves flow patterns over time.

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

3Weight of moving object

If support structures are made thinner to reduce mass, then engine performance is improved, but structural integrity during manufacturing may be compromised

Engineering Contradiction:
Improvesupport structure massVSAvoidstructural integrity
Core Design Contradiction:
Weight of moving objectVSStrength

Solution Approach 1:

The support structures exhibit local quality variations with different thicknesses, material compositions, and densities at different locations. Thinner sections are placed where minimal support is needed and faster erosion is desirable, while thicker or more robust sections are positioned where structural integrity is critical during manufacturing. This spatial variation in properties allows thin overall mass while maintaining local strength where required.

Inventive Principle:
Principle #3Local quality

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 enhances engine efficiency and performance by reducing the mass of support structures within the combustion chamber, allowing for more complex geometries and improved flow patterns without the need for additional manufacturing steps, while maintaining structural integrity.

Implementation Method 1

The support structure is configured to vaporize at a temperature of 1093° Celsius (2000 ° Fahtrenheit)

Methodology Applied
Scientific EffectVaporization: Evaporation

Data Source

PatentEP3633268B1Additively manufactured combustor shell with consumable support structures
Publication Date: 2021.05.05 RTX CORP
  • EP3633268B1 patent drawingFigure 1
  • EP3633268B1 patent drawingFigure 2
  • EP3633268B1 patent drawingFigure 3A~3B

AI summary

An additively manufactured combustor shell (104, 106) may comprise a radially outward surface (108), a radially inward surface (110) opposite the radially outward surface (108), and an injector port (120) defining a fuel injection channel (122). The injector port (120) may comprise an inlet structure (124) extending from the radially outward surface (108), and an outlet structure (126) may extending from the radially inward surface (110). A support structure (130) may extend between the outlet structure (126) and the radially inward surface (110). The support structure (130) may be configured to vaporize upon ignition of a fuel within the combustion chamber.