Enrico De Betta

Liquid hydrogen is a key enabler for decarbonizing aviation, offering zero in-flight CO ₂ emissions. However, effective cryogenic storage management, especially during extended ground operations, is essential to minimize losses from boil-off gas. This study explores strategies to reduce overnight hydrogen losses for an A320-type aircraft, which typically retains 10–15% of tank capacity after its final daily flight. Two refuelling strategies are analysed: leaving the tank at partial fill overnight, and immediate post-flight refuelling to full capacity. These are evaluated alongside two airside supply infrastructure configurations: centralized fixed cryogenic storage and mobile trailer-based delivery. The thermal behaviour of the system, including tank thermodynamics, pipeline transfer losses, and insulation performance, is modelled using multi-phase, reduced-order simulations. A sensitivity analysis investigates the effects of initial thermodynamic conditions, tank design, insulation quality, and hydrogen transfer parameters on total boil-off gas. Results show that hydrogen losses are minimized with 50–75% partial post-flight refuelling. This work offers practical guidance for airport hydrogen logistics and supports the integration of liquid hydrogen into commercial aviation fuel systems.

A preliminary analysis of aircraft refueling using liquid hydrogen (LH2) for a future short–medium-range aircraft is presented. The focus is on how selected refueling parameters influence pressure buildup and the release of boil-off gas (BOG), in order to establishing guidelines towards efficient refueling. The flow physics uses a 0-D multi-phase lump model, which accounts for the effects of the injected LH2, BOG release, heat fluxes and phase changes. Refueling is controlled by volumetric compression during the filling, and relaxation afterwards. Mass-flow profile and refueling protocol have little influence on the amount of BOG vented (~1%), but control the duration of the process, with variations close to 50%. Low initial pressure can significantly reduce the amount of BOG.