Integrated SOFC-Combustor Assembly for T4 Distribution Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current gas turbine engines face challenges in maintaining optimal combustor exit temperature (T4) distribution, leading to thermal stress and reduced life of turbine blades and nozzles, due to limited control flexibility of fuel and air manifolds in integrated Solid Oxide Fuel Cell (SOFC) systems.
Innovation Solution
The integration of SOFCs around the combustor liners, electrically grouped into control groups with adjustable current bias, allows for real-time adjustment of electrical current to achieve a desired T4 distribution across tangential, radial, axial, and circumferential directions, using power converters to control the electrical current and maintain a balanced temperature profile.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If SOFCs are integrated around combustor liners to improve fuel efficiency and reduce emissions, then energy conversion efficiency is improved, but control flexibility of fuel and air manifolds is reduced
Solution Approach 1:
The fuel cell system is divided into multiple independently controllable fuel cell stacks or modules, each with its own fuel and air manifolds. This segmentation allows individual control of each stack's power output and fuel consumption, restoring control flexibility while maintaining the integrated SOFC-combustor configuration for improved fuel efficiency
Solution Approach 2:
The fuel and air manifold systems are designed with dynamic control capabilities, including variable flow control valves and adjustable fuel injection rates. This enables real-time modulation of fuel and air flow to each fuel cell stack, allowing the system to adapt to varying power demands and maintain optimal combustion conditions while improving overall fuel efficiency
2Temperature
If SOFCs are integrated around combustor liners to achieve desired T4 distribution, then temperature distribution is improved, but device complexity increases
Solution Approach 1:
The combustor liner is divided into multiple axial and radial zones, with fuel cell stacks integrated into specific zones where temperature control is most critical. This selective zonal integration allows T4 distribution control in key areas without the complexity of complete circumferential integration throughout the entire combustor length
Solution Approach 2:
Fuel cell stacks are integrated only in specific regions of the combustor where local temperature control is needed to achieve desired T4 distribution. The integration density and configuration are varied locally based on thermal requirements, rather than uniform integration, reducing overall system complexity while maintaining temperature control effectiveness
3Power
If fuel cells consume compressed air to generate electrical energy, then power generation is improved, but air flow available for combustion is reduced
Solution Approach 1:
The system employs dynamic air flow management with variable control valves that adjust the split of compressed air between fuel cells and combustor in real-time. During high power generation demands, more air is directed to fuel cells; during combustion optimization phases, air allocation is adjusted to maintain optimal combustion efficiency, allowing both functions to operate at peak performance under different conditions
Solution Approach 2:
The system changes operational parameters by adjusting the compression ratio and air flow rates dynamically. The compressor operates at variable speeds and the air manifold system adjusts pressure distribution to optimize the balance between air consumption by fuel cells and air availability for combustion, enabling both power generation and combustion efficiency to be maximized at different operating points
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 approach effectively mitigates hot spots, achieves a more even T4 distribution, reduces thermal stress, and enhances the service life of turbine blades and nozzles while maintaining constant total power output.
Implementation Method 1
The plurality of fuel cells is configured to generate a fuel cell power output using fuel and air directed into the plurality of fuel cells
Implementation Method 2
the combustor is configured to combust the fuel and air exhaust from the plurality of fuel cells into one or more gaseous combustion products that power the turbine
Implementation Method 3
a turbine disposed downstream from the combustor. The turbine is configured to convert a portion of the gaseous combustion products into rotating energy that is used to power one or more loads
Data Source
AI summary
An integrated fuel cell and combustor assembly, and a related method. The assembly includes a combustor having a combustor geometry and a combustor exit temperature. The assembly further includes multiple fuel cells fluidly coupled to the combustor, the multiple fuel cells being configured to generate a fuel cell power output using fuel and air directed into the multiple fuel cells and to direct a fuel and air exhaust from the multiple fuel cells into the combustor. The multiple fuel cells include multiple fuel cell control groups arranged in a predetermined electrical configuration about the combustor geometry. Each of the multiple fuel cell control groups has an adjustable electrical current bias.