Solid Oxide Fuel Cell Performance and Sizing Model for Novel Aircraft Propulsion Conceptual Design

Novel aircraft propulsion concepts based on electrochemical conversion technologies, such as solid oxide fuel cells (SOFCs), are being investigated to enable climate-neutral air transport. It is crucial to identify SOFC architectures that are relevant and capable of fulfilling the specific requirements for aerospace applications, i.e., optimization for mass and volume. For a mature design and performance synthesis of propulsion system concepts, including highly integrated SOFCs, more sophisticated component models are necessary for a clean and unified integration of SOFC technology. The models should include both electrochemical performance and sizing, as well as system integration, already at the early stages of system design and analysis. This work presents a MATLAB-based 0D approach within the Bauhaus Luftfahrt Aircraft Propulsion System Simulation (APSS) framework to model the steady-state operational characteristics of an SOFC stack and determine its preliminary size. The results serve as a basis to assess integration aspects and challenges for various SOFC architectures, such as planar or microtubular arrangements. For simulated fuel cell stacks, validation studies are performed to ensure realistic dimensioning, as well as selected analyses showing the sensitivity of the model and resulting stack size to relevant operating parameters, such as temperature or required power. The studies presented within this work are an important step towards enabling the design and subsequent evaluation of overall fuel cell-driven propulsion system concepts.