Afterburner Temperature Measurement for Fuel Cell Enthalpy Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Solid oxide fuel cells (SOFCs) face challenges due to high operating temperatures, mechanical and chemical compatibility issues, and the formation of harmful carbon compounds that degrade the fuel cell process, requiring accurate measurement and control of fuel utilization and oxygen-to-carbon ratios, which is costly and complex with existing methods.
Innovation Solution
A fuel cell system that determines residual enthalpy change to minimize measurement and control requirements, using an afterburner to burn residual gas, measuring temperature differences, and calculating fuel input enthalpy and concentration to control fuel utilization and oxygen-to-carbon ratios, thereby reducing the need for expensive and inaccurate methane concentration measurements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If expensive and complex measurement devices are used to accurately measure methane concentration and control fuel utilization, then measurement precision and control accuracy improve, but device complexity and cost increase
Solution Approach 1:
The patent introduces an afterburner as an intermediary device to indirectly measure fuel composition and flow characteristics. Instead of directly measuring methane concentration with complex sensors, the system burns residual gas in the afterburner and measures the temperature rise, which serves as a mediator to infer fuel utilization and composition parameters with simpler equipment
Solution Approach 2:
The patent replaces complex mechanical/electronic measurement systems (methane sensors, flow meters) with a thermal measurement system. By substituting direct compositional measurement with temperature measurement in the afterburner, the system achieves equivalent control information using simpler, more reliable thermal sensors
2Use of energy by moving object
If high operating temperatures are used in SOFCs, then energy conversion efficiency improves, but harmful carbon compound formation increases and mechanical compatibility deteriorates
Solution Approach 1:
The patent implements a feedback control system where afterburner temperature measurements provide continuous information about fuel utilization and composition. This feedback loop allows real-time adjustment of fuel input and air supply to maintain optimal combustion conditions, preventing excessive carbon compound formation while preserving high efficiency operation
Solution Approach 2:
The patent dynamically adjusts operational parameters (fuel flow rate, air supply to afterburner) based on measured afterburner temperature. By changing these parameters in response to thermal feedback, the system maintains efficient energy conversion while controlling the formation of harmful carbon compounds through optimized combustion conditions
3Reliability
If fuel utilization and oxygen-to-carbon ratios are tightly controlled to prevent coking, then service life and reliability improve, but device complexity and measurement requirements increase
Solution Approach 1:
The afterburner temperature serves as an intermediary parameter that indirectly reflects fuel utilization and oxygen-to-carbon ratios. By monitoring this thermal mediator rather than directly measuring multiple compositional parameters, the system achieves reliable control of fuel cell operation to prevent coking with reduced complexity
Solution Approach 2:
The afterburner temperature measurement serves multiple functions simultaneously: it indicates fuel utilization, reflects fuel composition changes, and provides control feedback for preventing coking. This multi-functional use of a single measurement simplifies the control system while maintaining reliability
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 allows for cost-effective measurement and control of fuel utilization and oxygen-to-carbon ratios, significantly reducing errors and extending the service life of SOFCs by preventing carbon compound formation, and potentially eliminating the need for precise feed-in flow and composition information.
Implementation Method 1
an afterburner for performing burning of residual gas from the anode side
Implementation Method 2
means for measuring temperature before and after the afterburner to form afterburner temperature difference
Implementation Method 3
energy of fuel, for example blogas, Is directly converted to electricity via a chemical reaction
Implementation Method 4
The negative oxygen ion goes through the electrolyte material 104 to the anode side 100
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An object of the invention is an arrangement, which comprises means (125) for measuring temperature in the afterburner (123) or substantially near the afterburner (123) to form afterburner temperature change information, means (127) for determining information on consumed fuel amount in the fuel cells (103) on the basis of the current information, means for determining information on air amount in the afterburner (123), means (133) for determining residual enthalpy change information on the basis of said afterburner temperature change information, said information on air amount in the afterburner, and on the basis of said information on consumed fuel amount in the fuel cells. The means (120) for obtaining at least one of fuel input enthalpy information and fuel input concentration information on the basis of the determined residual enthalpy change information, said means (120) being configured to determine methane content information of the fuel feed (117) by utilizing said obtained at least one of fuel input enthalpy information and fuel input concentration information.