Failure process analysis of frustum windows for deep-sea manned cabin

The commonly used acrylic frustum windows are the weakest components in the deep-sea manned cabin of the submersible. The short-term collapse test is typically required by full or scale model test, which can applied to measure the critical pressure but cannot tell when the structure begins to damage and how the damage continues. To make up for the deficiency, it is necessary to develop the design-by-analysis methodology. In this paper, numerical analysis for the pressurisation process of the frustum windows considering two failure criteria is carried out to capture the initial failure pressure and location. An effective way to study the detailed failure status and failure process of window under pressurisation is provided. The results are regressed as functions and compared with the values of conversion factor applied in window's design based on ASME specification, which will provide reference for safe design based on determining safety factor reasonably.