Numerical evaluation of type I pressure vessels for ultra-deep ocean trench exploration

Oceans are areas on our planet which remain largely unexplored. This is mainly due to the considerable challenges involved in underwater exploration. So far the majority of surveys are carried out using Remotely Operated Vehicles (ROVs) and Automated Unmanned Vehicles (AUVs). These vehicles, despite their impressive capabilities, have several limitations, especially in terms of their operational endurance. Moreover, a very small number of ROVs have been qualified for operations in depths beyond 6 km. The use of ROVs in ocean trenches involves extremely complex operations and is not free of risk. The deepest known point is Challenger Deep at the Mariana Trench in the Pacific Ocean, with a maximum depth of just under 11 km. Only a handful of manned and unmanned missions have managed to reach this depth since Piccard's mission in 1960, on-board the bathyscaphe Trieste. Herewith we report on the finite elements analysis of type I pressure vessels for hydrogen storage to be used in future AUVs with long endurance capability for ultra-deep exploration.