Gas Turbine Combustor Liner Cap Assembly Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The conventional combustor liner cap assembly in industrial gas turbines is labor-intensive and costly, while requiring improved thermal expansion management and secure attachment of premix tubes, along with adjustable nozzle guides to accommodate fuel nozzle assemblies.
Innovation Solution
A combustor liner cap assembly with a tube plate and cylindrical sleeve design, where premix tubes are metallurgically bonded or threaded to the tube plate, and nozzle guides are retained with radially extending flanges and retaining members, allowing for sliding adjustment and secure positioning.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If the conventional combustor liner cap assembly construction is used, then the structural attachment of premix tubes is provided, but the manufacturing cost and labor intensity increase
Solution Approach 1:
The combustor liner cap assembly is divided into modular components: a cap body with integrated nozzle guides, a separate premix tube assembly with forward edges, and distinct retention members. This segmentation allows each component to be manufactured independently using optimal processes, reducing overall manufacturing complexity and cost while maintaining structural integrity through designed interfaces between segments.
Solution Approach 2:
The nozzle guides are merged with the cap body as an integrated structure, eliminating the need for separate nozzle guide components and their associated retention mechanisms. This merging reduces the number of parts, simplifies assembly, and lowers manufacturing costs while ensuring stable positioning of the premix tubes through the integrated guide structure.
2Strength
If the premix tubes are securely attached to accommodate thermal expansion, then the structural integrity is maintained, but the device complexity increases
Solution Approach 1:
The retention members are designed to provide secure attachment of premix tubes while accommodating dynamic thermal expansion movements. The retention structure allows for controlled movement in the thermal expansion direction while maintaining firm attachment in other directions, thus providing both structural integrity and thermal flexibility without complex mechanisms.
Solution Approach 2:
The design explicitly accounts for thermal expansion by providing clearance and movement pathways for the premix tubes at their forward edges. The retention members secure the tubes while allowing them to expand thermally, and the integrated nozzle guides provide stable positioning that accommodates this expansion without compromising structural integrity.
3Adaptability or versatility
If the nozzle guides are retained in a floating relationship for adjustment, then the adaptability for nozzle insertion is improved, but the positioning stability may be compromised
Solution Approach 1:
The nozzle guides are segmented from the premix tubes, allowing the guides to be positioned and adjusted independently within the cap body. This segmentation enables the guides to float for accommodation of nozzle insertion variations while their integrated connection to the cap body provides stable positioning, resolving the contradiction between adaptability and precision.
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 design enhances cost-effectiveness and structural integrity, accommodating thermal expansion and nozzle assembly insertion while maintaining a smooth gas flow path, reducing labor and material costs.
Implementation Method 1
each premix tube may be metallurgically bonded, such as by welding or brazing to the tube sheet
Implementation Method 2
each premix tube may be metallurgically bonded, such as by welding or brazing to the tube sheet
Data Source
AI summary
A combustor liner cap assembly is provided for use in a multiple fuel nozzle combustor of a gas turbine. The combustor liner cap assembly includes a tube plate having a plurality of fuel nozzle openings and a plurality of open ended premix tubes extending aft from the tube plate. Each premix tube has a forward end having a forward edge, the forward end being received in a corresponding one of the fuel nozzle openings. Each premix tube is secured to the tube plate aft of the forward edge of the forward end of the premix tube, for example, metallurgically bonded, such as by welding or brazing, to the tube plate or threaded into the tube plate.