A numerical approach to design a type II box-shaped pressure vessel with inner tension struts

The use of shared vehicle architectures with BEVs offers a high potential for FCEVs in terms of cost reduction. Therefore, the hydrogen must be stored in the box-shaped design space in the underbody of the vehicles, where the battery in BEVs is located. Box-shaped pressure vessels show the potential to store high amounts of hydrogen in this design space. An optimal design of a type I box-shaped pressure vessel with inner tension struts is investigated in literature. In this study, the relatively low efficiency of this type of pressure vessel is presented first. This motivates to work out the possibilities to increase the efficiency by reducing the total weight. Therefore, a numerical analysis is conducted to reinforce the vessel wall with fiber reinforced composite in the main section of this study. In a first step the possible measures to reinforce the pressure vessel are analyzed and evaluated. Then, a basic design, which serves as a baseline for the numerical studies, is determined analytically. Using a numerical model, the structure of the reinforcement and the acting loads are investigated with finite element method in parametric studies varying several parameters. Based on the knowledge gained, optimal design parameters are derived. These design parameters allow a comparison of the pressure vessel efficiency with other pressure vessel types and enable the evaluation of this vessel concept.