Structural design of flexible vacuum insulation system for large-scale LH2 storage

This study describes a new vacuum insulation system, consisting of a flexible vacuum membrane and a load-transferring insulation layer comprising polyurethane foam (PUF), for large-scale LH2 storage tanks. The vacuum membrane has a novel corrugated geometry to accommodate in-plane displacements induced by the thermal contraction of the inner tank, whereas the PUF layer transfers the external pressure load acting on the outer membrane onto the inner tank. To demonstrate and validate the overall performance of the proposed vacuum insulation system during extreme cooling at - 253 degrees C; it is applied to a 12,500-m3-LH2 tank of the "lattice pressure vessel" type. Geometrically non-linear elastic -plastic analysis results show that the vacuum membrane deforms elastically under normal operating conditions of 1 atm pressure and 3 mm/m contraction displacement. The membrane is capable of withstanding harsh conditions, where both the pressure and displacement loads increase significantly. (c) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.