Study On The Structural Performance Of Submarine Spherical Shell

As one of the two most important battleships of navy, the diving depth increase of submarine is always the pursuit. In the deep diving request, there are important theoretical significance and practical engineering value to conduct the research in spherical shell structure properties of submarine. This paper, for the composite structure and large-scale features of spherical shell under submarine hull compression, adopts finite element method to analyze its boundary condition and initial geometric imperfection sensitivity. The main work is as follows:(1) Expounds the theory about structure stability, derives and analyzes the nonlinear buckling theory of spherical shell structure in small deformation and large deflection cases.(2) Introduces the present situation of combination shell structure analysis, verifies the reliability of using the finite element method in combination shell structure combining with the model, designes the ring ribs cylindrical shell combination pressure-tight shell of the spherical shell sealing head according to GJB2001 "The submarine structure design and calculation method"(3) Analyzes the combination shell structure, gets shell structure thickness of spherical submarine with an equivalent stiffness of ring-stiffened cylindrical, analyzes the structural design features and the boundary under calculation, and gives out the boundary correction factor.(4) Analyzes the influences of the initial geometric imperfection to the bearing capacity of submarine spherical shell structure using the nonlinear finite element method. By analyzing the width,amplitude,defect position factors, gets the law of local initial geometric imperfection on critical load and critical defects arc(scale effect)and the law of boundary to defect under the large scale condition of submarine spherical shell structure(boundary effect).