Ellipsoidal compressed gaseous hydrogen CFRP vessels with increased energy storage density: Combined analytical–numerical design methodology

Compressed gaseous hydrogen (CGH 2 ) vessels must achieve high volumetric energy densities at pressures up to 70 MPa and enhanced gravimetric performance to meet aviation requirements. A critical deficit is the unavailability of efficient iterative design processes for design space optimized composite CGH 2 vessels that integrate reliable, predictive models with manufacturing constraints and an accurate representation and optimization of the carbon fiber-reinforced polymer (CFRP) laminate layup as an essential prerequisite for efficient vessel design and virtual certification. This work proposes a combined analytical-numerical approach for the design of CFR-epoxy wound ellipsoidal CGH 2 vessels. An optimum laminate layup to achieve isotensoid stress states considering non-geodesic fiber placement is analytically determined and mapped on a numerical model to perform burst pressure simulations. Fiber stress distributions and inter-fiber failure are analyzed using Puck criterion to identify necessary design iterations. The elaborated methods enable an efficient development of ellipsoidal composite CGH 2 vessels with increased volumetric design space utilization and gravimetric storage density. Furthermore, it offers considerable potential for flexible adaptation and transferability to other vessel geometries or size scales.