Turbomachine Fuel Injector Polygonal Duct for Additive Manufacturing

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The existing fuel injectors for axial fuel staging (AFS) systems in turbomachines require numerous temporary supports during additive manufacturing, leading to increased production time and costs due to the need for post-machining to remove these supports.

Innovation Solution

The design incorporates a fuel injection assembly with a fuel injector featuring a polygonal segment and cylindrical inlet segment in the fuel duct, allowing for additive manufacturing with minimal temporary supports and reducing the need for post-machining, thereby simplifying the production process.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If complex structural geometries and internal circuits are implemented in AFS fuel injectors using additive manufacturing, then functional performance is improved, but the number of temporary supports required increases

Engineering Contradiction:
Improvefunctional performanceVSAvoidnumber of temporary supports
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The fuel injector body is segmented into distinct functional zones (fuel plenum, mixing section, spray outlets, internal circuits) that can be additively manufactured with minimal supports. The segmentation allows each zone to be optimized independently for manufacturing feasibility while maintaining overall functional performance.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The design incorporates curved and rounded geometries in the fuel injector structure that are more amenable to additive manufacturing processes. These curved features reduce the need for temporary supports compared to sharp angles or complex intersections, while still achieving the required functional performance.

Inventive Principle:
Principle #14Spheroidality (Curvature)

2Strength

If numerous temporary supports are used during additive manufacturing of AFS fuel injectors, then structural integrity during fabrication is maintained, but production time increases

Engineering Contradiction:
Improvestructural integrity during fabricationVSAvoidproduction time
Core Design Contradiction:
StrengthVSProductivity

Solution Approach 1:

The design extracts and eliminates the need for numerous temporary supports by optimizing the fuel injector geometry. Features are designed to be self-supporting during additive manufacturing, removing the requirement for post-machining support removal and reducing production time while maintaining structural integrity.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The fuel injector geometry is preliminarily optimized during the design phase to ensure self-supporting structures during additive manufacturing. This preliminary design consideration prevents the need for temporary supports and subsequent removal operations, directly reducing production time.

Inventive Principle:
Principle #10Preliminary action

3Stability of the object's composition

If numerous temporary supports are used during additive manufacturing, then fabrication stability is maintained, but post-machining requirements increase

Engineering Contradiction:
Improvefabrication stabilityVSAvoidpost-machining requirements
Core Design Contradiction:
Stability of the object's compositionVSEase of manufacture

Solution Approach 1:

The design extracts and eliminates temporary supports from the manufacturing process by optimizing fuel injector geometry for self-supporting additive manufacturing. This removes the need for post-machining support removal operations, simplifying the manufacturing process while maintaining fabrication stability.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The fuel injector structure is designed to be self-supporting during additive manufacturing, serving its own structural needs without external temporary supports. This self-service approach eliminates the need for post-machining removal operations and simplifies the overall manufacturing process.

Inventive Principle:
Principle #25Self-service

Data Source

PatentEP3974725B1Fuel injection assembly for a turbomachine
Publication Date: 2023.12.27 GENERAL ELECTRIC TECH GMBH
  • EP3974725B1 patent drawingFigure 1~2
  • EP3974725B1 patent drawingFigure 3~4
  • EP3974725B1 patent drawingFigure 5

AI summary

A fuel injection assembly (200) includes a fuel injector (202) having a first annular wall (214) that about an axial centerline (216) and extends from a primary inlet (220) disposed at a first end (222) to a primary outlet (224) disposed at a second end (226). A second annular wall (230) surrounds the first annular wall (214). A fuel plenum (232) is defined between the first annular wall (214) and the second annular wall (230). A fuel duct (208) extends from a fuel outlet (240) defined in the second annular wall (230) to a fuel inlet (242). wherein the fuel duct (208) is in fluid communication with the fuel plenum (232). The fuel duct (208) includes a polygonal segment (244) and a cylindrical inlet segment (246). The polygonal segment (244) extends from the fuel outlet (240) to the cylindrical inlet segment (246).