Integrated Fuel Feed Passages for Sequential Injector Flow Testing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional fluid dispensing systems in attritable aircraft engines are complex, expensive, and difficult to maintain due to numerous parts, which complicates inspection and testing, particularly in limiting the accessibility for isolating and testing individual fuel injectors efficiently.
Innovation Solution
An additively manufactured attritable engine with integrated fuel feed passages allows for thermal communication with the exterior surface, enabling the temporary blocking of flow to other injectors by inducing a phase change in the fuel feed passages, allowing for sequential flow testing of each injector.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If conventional fluid dispensing systems with multiple parts are used, then the system can be assembled with standard components, but the manufacturing cost and assembly time increase significantly
Solution Approach 1:
The fuel feed passages are integrated directly into the engine case wall structure, merging the fuel delivery function with the engine housing. This eliminates the need for separate fuel rails and multiple brazing operations, reducing both part count and manufacturing cost while maintaining fuel distribution functionality
Solution Approach 2:
The engine case wall serves multiple functions: it provides structural housing, thermal management, and integrated fuel distribution through embedded cavities and passages. This multi-functionality reduces the need for separate dedicated fuel delivery components
2Ease of manufacture
If conventional fuel rails with multiple brazed parts are used, then standard manufacturing processes can be applied, but the manufacturing time and cost increase
Solution Approach 1:
The fuel feed passages are formed as integral parts of the engine case wall through additive manufacturing, combining what would traditionally be separate brazed components into a single monolithic structure, thereby eliminating assembly time
Solution Approach 2:
The manufacturing method transitions from traditional subtractive or assembly-based approaches to additive manufacturing, changing the fundamental manufacturing parameter from multi-step assembly to single-step fabrication, which reduces time while maintaining flexibility
3Measurement precision
If CT scanning is used to inspect each injector, then comprehensive inspection can be performed, but the testing time and cost increase significantly
Solution Approach 1:
The fuel system is segmented into individual cavities within the engine case wall, each providing isolated access to specific injectors. This allows sequential testing of individual injectors without requiring comprehensive scanning of the entire engine, reducing testing time while maintaining inspection quality
Solution Approach 2:
The embedded cavities act as intermediary access points that enable direct, localized inspection of individual injectors. These cavities serve as mediators between the testing equipment and the injectors, allowing efficient sequential testing without the need for invasive or time-consuming CT scanning of the entire engine
4Ease of manufacture
If conventional fuel dispensing systems with many operating parts are used, then the system can be assembled with standard components, but the maintenance and repair costs increase
Solution Approach 1:
By integrating the fuel feed passages into the engine case wall, the system reduces the number of separate operating parts that require maintenance. The integrated structure eliminates potential failure points at connection interfaces between separate components
Solution Approach 2:
The embedded cavities provide localized access to individual injectors, enabling targeted maintenance and repair of specific components without affecting the entire fuel system. This localized accessibility reduces maintenance complexity and cost
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 method simplifies the testing process, reducing costs and time compared to conventional techniques like CT scanning, while ensuring each injector meets stringent flow requirements, thereby improving manufacturing efficiency and reducing maintenance needs.
Implementation Method 1
a fuel feed passage that is in thermal communication through the exterior surface of the engine case wall
Implementation Method 2
inducing a phase change to a flow test fluid in each of (N−1) fuel feed passages, which prevents flow through each of (N−1) injectors
Data Source
AI summary
An additively manufactured attritable engine includes a compressor section, a combustion section, a turbine section, and an engine case wall, which surrounds the compressor section, the combustion section, and the turbine section. The engine case wall includes a first cavity embedded in the engine case wall that defines an injector that is in fluid communication with the combustion section. The engine case wall includes a second cavity embedded within the engine case wall and defines a fuel feed passage that is in thermal communication through the exterior surface of the engine case wall.