Review of Liquid Hydrogen Tanks’ Design Principles for Short- and Medium-Range Civil Flights

The aviation industry plays a significant role in global transportation but has raised concerns about its contribution to climate change due to greenhouse gas emissions. Decarbonizing the aviation sector is crucial to align with global climate goals as aviation emissions have a disproportionately higher climate impact and could triple by 2050 if no mitigation actions are taken. Liquid hydrogen has emerged as a promising sustainable fuel alternative for aviation due to its high-energy density and zero-carbon emissions. Its combustion only produces water vapor, eliminating carbon dioxide emissions associated with conventional fossil fuels. Advancements in hydrogen production, storage, and distribution technologies have increased the potential for scalable and sustainable hydrogen infrastructure for aviation. However, challenges such as hydrogen availability, infrastructure development, and safety considerations need to be addressed for widespread adoption. Cryogenic tank design plays a crucial role in storing cryogenic fluids like liquid hydrogen. Different insulation strategies, including vacuum insulation, multilayer insulation, powder insulation, and foam insulation, are used to minimize heat transfer and pressure increase in cryogenic tanks. Liquid hydrogen tanks also need to consider phenomena such as ortho-para conversion and cryo-pumping, which can lead to pressure increases and heat transfer. While boil-off is a major concern in ground tanks, it is less critical in aircraft tanks due to the ability to utilize some of the boil-off gas. Overall, the design strategies and concepts behind the storage of liquid hydrogen for aircraft are essential for enabling a sustainable and environmentally responsible path forward in the aviation industry.