**2.1 Basic structural configuration and FEA design parameters**

Any composite overwrapped pressure vessel (COPV) design requires an analysis of the liner, the fiber overwrap, and the interaction between the two. COPV liners may be of ductile materials with only minimal load-sharing capabilities, such as ductile metal composites [11–19], glass fiber reinforced angle interlock composites [20–22], or carbon fiber reinforced composite oriented strand boards [5, 23–29].

The general layout and components of the baseline cross-section design (Section "A") are presented in **Figure 2a**. The outer diameter of Section "A" is roughly 60 cm. The design variables for the optimization of the circular cross-section "A" are presented in **Figure 2b**. These design variables are modified systematically throughout the design exploration procedure, allowing for different evolving design configurations.

In the same manner, four different probe locations were defined (**Figure 2c**) to obtain stress and displacement results of the tested cross-section designs and allow a quantitative comparison of the effects of each individual design variable, their respective interactions and the overall behavior of the different design configurations. These probing locations will be used for all the analysis carried out in order to obtain consistent results.
