Safety Evaluation Of External Pressure Spherical Shell Of Jiaolong

In recent years,with the rise of marine development,the safety of deep submersibles has received increasing attention from researchers and scientists.The external pressure spherical shell is a key component of the deep submersible.It can carry researchers to the depth of the sea for on-site observation and operation.External pressure spherical shells need to ensure the normal operation of deep-submersible equipment and provide normal working and living space for researchers.Therefore,the external pressure spherical s hell must ensure sufficient structural strength and stability.Therefore,it is of great significance to carry out a comprehensive safety assessment study on the spherical shell of the submersible.The paper applies the fault tree analysis method and fuzzy comprehensive evaluation theory to the safety evaluation of external pressure spherical shells,which provides a new method and new ideas for the comprehensive safety evaluation of external pressure spherical shells.Firstly,based on the processing and manufacturing process of pressure shells for deep diving equipment in China,the factors affecting the safety of external pressure spherical shells are summarized and analyzed,and using fault tree analysis method established a fault tree model for these influencing factors,then the fault tree model is qualitatively and quantitatively analyzed to obtain the minimum cut set and structural importance of the fault tree.Secondly,using ANSYS,WORKBENCH finite element software to carry out static analysis and nonlinear buckling analysis of the spherical shell,the influence of the main influencing factors on the safety of the external pressure shell is obtained.Finally,the theory of fuzzy comprehensive evaluation in fuzzy mathematics is applied to the safety evaluation of external pressure spherical shells.A comprehensive safety evaluation method for the external pressure spherical shell of deep diving devices is proposed,a safety evaluation model is established,and the proposed method is used.Example calculations verify the feasibility of the proposed method.