A Knowledge-Based Framework for a Crashworthy Integration of a Liquid Hydrogen Tank into a Conceptual Aircraft

Abstract

Liquid hydrogen-powered aircraft are a promising candidate for reducing aviation’s climate impact, but safe integration requires crashworthiness considerations already at conceptual design. This work presents a parametric, knowledge-based methodology to design and analyse a fuselage-located cryogenic tank supported by a belly crash structure under a vertical drop test. The methodology is implemented in a parametric application that automatically generates geometry from readily adjustable inputs, enabling quick generation of a wide variety of configurations. A baseline configuration, consisting of 12 sub-tank X-beams per bay configured in six X-crosses, a stiff crossbeam design, and distributed Kevlar tank suspension ropes, exhibited favourable deformation kinematics. A design-of-experiments study was conducted and combined with a surrogate-model-based sensitivity analysis to identify the dominant design parameters governing the crash response. Results show that the coupled frame and crossbeam thickness, together with the crash coefficient, are the most influential. Including a crash structure substantially increases the required tank and fuselage length, and the associated mass penalty is dominated by the added tank and fuselage structure rather than by the crash structure mass. The developed model provides a basis for further research on structural mass optimisation and for providing data for a surrogate integration into a conceptual aircraft design tool.