Design of a Cryogenic Airborne Hydrogen Cooling System for Electric Propulsion

This paper focuses on an innovative approach for the layout of an airborne cryogenic hydrogen cooling system for an electric power train. With climate change related challenges becoming increasingly severe, the need for low-emission, sustainable air mobility solutions, such as hydrogen fuel cell powertrains, is apparent. Novel technological approaches entail challenges regarding their development processes. Need-adapted systems engineering must assure that a high system of systems complexity can be fully understood down to component level, and all necessary information is captured and properly represented to identify appropriate design decisions as well as critical causal chains. This paper describes the authors' approach to designing a cryogenic hydrogen cooling system for an axial flux motor, destined for aeronautic application. The hydrogen cooling system is designed for operation within a powertrain with the superordinate input parameters chosen such that to fit the typical mission profile of a regional distance aircraft. For the system modelling, MBSE and cognitive mapping concepts are applied, with the objective to evaluate the causal chains and relationships between operation parameters (of the cooling system), and to establish statements about system architecture and component design as well as cooling performance. Thereby, the cooling system behavior is simulated using analytical thermodynamics and fluid mechanics as well as CFD simulations to support the system modeling and causal chain evaluation.