Coiled Fuel Tube Flexibility for Turbomachine Injector Durability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional fuel nozzle systems for turbomachines are heavy, limited in size and number, and prone to durability issues, which restricts the ability to produce an optimal fuel-air mixture and emissions control, leading to inefficiencies in mixing and increased workload on the combustor.
Innovation Solution
A fuel injector system with a coiled fuel tube that allows axial movement and flexibility between the fuel manifold and combustor dome, integrated with a heat shield structure and standoff features for alignment, enabling multiple fuel injectors to mix air and fuel efficiently and reduce air blockage, while using retainer rings for secure mounting and radial staging.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If traditional fuel nozzles are used with external fuel manifolds and floating air seals, then the system is simpler in structure, but the fuel injectors become heavy and limited in size and number, reducing mixing efficiency and increasing combustor workload
Solution Approach 1:
The fuel injector is merged with the combustor dome structure, eliminating the need for separate external fuel manifolds and floating air seals. The fuel injector body integrates directly into the combustor dome, combining multiple functions (fuel delivery, sealing, structural support) into a single integrated component, thereby reducing overall system weight and increasing injection capability
Solution Approach 2:
The fuel injector body serves multiple functions simultaneously: it acts as a structural component of the combustor dome, provides fuel delivery through internal channels, maintains sealing through integrated seals, and supports the fuel tube flexibility requirement. This multi-functionality eliminates the need for separate dedicated components for each function
2Ease of manufacture
If traditional fuel nozzles with external manifolds are used, then manufacturing is simpler, but the system is limited in the number of fuel injectors that can be installed, reducing mixing efficiency
Solution Approach 1:
The fuel injection system is segmented into multiple independent fuel injectors that can be individually positioned around the combustor dome. Each fuel injector is an independent unit with its own fuel tube and distribution system, allowing multiple injectors to be installed without interfering with each other, thereby increasing the total number of injection points for improved mixing
3Stability of the object's composition
If rigid fuel tubes are used to connect fuel manifold and combustor dome, then structural stability is better, but thermal expansion and contraction cause durability issues
Solution Approach 1:
The fuel tube is designed with flexibility to accommodate thermal expansion and contraction between the fuel manifold and combustor dome. The fuel tube can dynamically adjust its position and shape in response to temperature changes, preventing stress concentration and durability issues while maintaining reliable fuel delivery
Solution Approach 2:
The fuel tube's physical parameters (flexibility, expansion coefficient) are specifically designed to match the thermal behavior of the combustor components. By selecting materials and configurations with appropriate thermal expansion characteristics, the system maintains structural integrity and reliability under varying thermal conditions
4Productivity
If fuel injectors are positioned to maximize fuel delivery, then combustion efficiency improves, but air flow blockage increases
Solution Approach 1:
The fuel injector design incorporates local quality variations in the fuel tube configuration and injection angle to optimize the balance between fuel delivery and air flow. By carefully designing the local geometry of fuel delivery paths and injection orientations, the system achieves effective combustion while minimizing air flow blockage in critical regions
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 system achieves efficient combustion with increased mixing control, reduced size and weight of the turbomachine, improved durability, and low emissions by allowing a high density of fuel injection points, uniform heat distribution, and minimized air flow blockage.
Implementation Method 1
The fuel tube is configured to move in an axial direction to allow flexibility between the fuel manifold and the combustor dome. The coiled fuel tube can be configured to axially compress and/or expand between the first end and the second end.
Implementation Method 2
The body can be formed from an outer heat shield and an inner heat shield disposed within the outer heat shield. The inner heat shield can at least partially define the air cavity.
Implementation Method 3
Each fuel injector can be disposed in a radially outward row and radially inward row are angled relative to an axial axis to effuse fuel and air into the combustor liner parallel to or away from walls of the combustor liner
Data Source
AI summary
A fuel injector for a multipoint injection system can include a body defining an air cavity for allowing air to flow therethrough and an interior cavity. A fuel is tube disposed at least partially within the interior cavity of the body. The fuel tube can include a first end configured to connect to a fuel injector connector of a fuel manifold, and a second end configured to connect to a fuel distributor of the fuel injector, wherein the fuel injector is configured to be disposed at least partially in a combustor dome. The fuel tube is configured to move in an axial direction to allow flexibility between the fuel manifold and the combustor dome.