Session: 01-11 Electrified Propulsion and Novel Cycles I

Paper Number: 151606

Design of Fuel Cell Systems in Aviation – Part II: Evaluation and Mission Analysis 

The use of polymer electrolyte membrane fuel cells (PEMFC) to generate the required propulsion power is a promising approach to reduce the climate impact of aviation. This requires a complex overall system, including an air supply system and a thermal management. The air supply system ensures a continuous supply of conditioned air to the fuel cell stack and consists of a compressor, heat exchanger, humidifier, turbine and electric motor, whereas the thermal management controls the heat dissipation of all heat sources in the fuel cell system. Both systems have a decisive influence on the system performance and mass.

For the design of such a PEMFC system a detailed consideration of the individual subcomponents as well as an overall system analysis is necessary. Further, effects on the aircraft performance should be considered for the entire flight mission. Therefore, in the first part of this two-part paper, an initial design workflow was presented, focussing on the turbo components of the air supply system and the heat exchangers to dissipate both the waste heat of the fuel cell stack and of the supplied air. Critical operating points and boundary conditions were identified using a cycle calculation model including the fuel cell stack as well as the air supply system.

The first objective of this part II is the integration of the previous designed components into the overall system calculation to cover interdependent interactions. For this purpose, the compressor and turbine performance maps, as well as the thermal management design generated in part I are embedded into the cycle calculation model. Thereby, the effects on the propulsion power requirement of the aircraft due to component masses and additional drag caused by the fuel cell heat exchanger are taken into account. The overall design process is iterative, as critical operating points can change as a result of updated boundary conditions.

The second focus of this study is to evaluate the entire flight mission of the reference aircraft with different numbers of cathode air supply systems regarding the influences on key system parameters such as fuel consumption, waste heat and system mass. In addition, different fuel cell operating strategies and critical scenarios such as hot day take-off are investigated.

Presenting Author: Patrick Meyer Institute of Jet Propulsion and Turbomachinery, Technische Universität Braunschweig

Presenting Author Biography: The author studied mechanical and aerospace engineering at the Technische Universität Braunschweig from 2017 to 2023. He is currently a PhD student and working as research assistant at the Institute of Jet Propulsion and Turbomachinery at TU Braunschweig. He is participating in the project "Design Space Evaluation of the Air-, Heat- and Power-Management of Fuel Cells for Aviation" (DEFCA) of the Cluster of Excellence "Sustainable and Energy Efficient Aviation" (SE²A).

Authors:

Patrick Meyer Institute of Jet Propulsion and Turbomachinery, Technische Universität Braunschweig
Marcel Stoewer Institute of Turbomachinery and Fluid Dynamics, Leibniz Universität Hannover
Marius Nozinski Institute of Thermodynamics, Leibniz Universität Hannover
Sebastian Lück Institute of Jet Propulsion and Turbomachinery, Technische Universität Braunschweig
Stephan Kabelac Institute of Thermodynamics, Leibniz Universität Hannover
Dajan Mimic Institute of Turbomachinery and Fluid Dynamics, Leibniz Universität Hannover
Jens Friedrichs Institute of Jet Propulsion and Turbomachinery, Technische Universität Braunschweig
Jan Goeing Institute of Jet Propulsion and Turbomachinery, Technische Universität Braunschweig