Design, optimization, and integration of passively-insulated liquid hydrogen tanks for sustainable aviation

A framework for the optimization of hydrogen pressure vessels is developed based on a passively insulated sandwich-composite architecture, aiming to combine high gravimetric efficiency and low boil-off rate for aircraft applications. The proposed computational tool integrates multiphysics finite-element modelling with nonlinear constraint-based multidisciplinary optimization, accounting for realistic features such as standardized safety factors, airframe integration, non-spherical domes, refuelling cutouts, and anti-sloshing baffles. The optimal design space of such storage systems is explored, showing that all-metal constructions strongly penalize performance, yielding gravimetric efficiencies below 30%. Conversely, composite-based tanks achieve up to 50% efficiency with mass reductions of 57% even when realistic features are included. Scaling effects are assessed, integrating the optimized system into a sustainable aircraft concept and identifying directions to mitigate the performance gap with conventional kerosene-fuelled aviation.