Conceptual Codesign of Cryogenic Storage and Ballast Systems for Hydrogen Airliners

Hydrogen is nowadays regarded as one of the possible replacements for kerosene as the main fuel for the aviation sector. However, its very low density at ambient conditions is a significant limitation that requires novel onboard fuel storage technologies to be developed. This paper presents results of a conceptual study on a liquid hydrogen (LH2) storage system for the rear fuselage of short/medium range (SMR) airliner, conducted in the frame of the EU-funded AirCraft Architecture Project (ACAP) research program. A structural optimization of the tank geometry is used to assess the effects of the gravimetric index on the mass and dimensions of the storage system. The extracted models are implemented in mass and center-of-gravity (CG) calculations used for the design of four potential ballast configurations, used to control the CG range within acceptable limits. A top-level performance optimization of each aircraft configuration is performed based on a flight probability density function describing the aircraft’s expected mission requirements; the results of this analysis are detailed and discussed. Finally, conclusions are presented on the feasibility, advantages, and disadvantages of different tank/ballast system configurations for the LH2 SMR airliner.