Liquid hydrogen (LH2) as an energy source is viewed as a potential path to achieve carbon neutral commercial aviation, albeit accompanied by a plethora of structural, thermal and safety challenges that still need to be resolved. With respect to a LH2 tank’s structural integration aspect, static, damage tolerance and impact/crashworthiness responses need to be investigated. Ιn the present work, an efficient structural integration concept of LH2 tanks into a Regional Commercial Aircraft fuselage is proposed, analyzed and preliminary designed, as part of the Clean Aviation project HERFUSE. The main purpose of the work is the feasibility assessment of introducing adhesively bonded solutions in the connection of LH2 tanks to the aircraft fuselage. The initial design of the potential mounting system configuration was investigated via a finite element parametric simulation model that was developed for this purpose and used to analyze different variations in the proposed concept, under certification relevant load cases. Different variations in the mounting system were assessed, considering their effect on the stress concentrations developed in the fuselage and the tank structure, as well as induced deformations and potential joints debonding. The results indicated that the utilization of adhesive bonding elements in the design of an LH2 tank integration system is conceptually efficient, although the specific configuration-related shortcomings that were identified need to be tackled. As far as the preliminary design study results are concerned, the minimum required number of joining elements were identified and an initial mass prediction of the mounting system was performed to be used as initial value in the entire hybrid–electric novel aircraft design loop. Future studies on the detailed design and sizing of the mounting system, as well as to incorporate dynamic crash analyses and implementation of energy absorbing elements are needed.
Gyftos et al. (Mon,) studied this question.