Research On The Stability And Experiment Design Of Sphere-cylinder Combined Shell Structure

As an important weapon in modern warfare,the stability of the pressure shell is related to its ultimate submergence depth and safety in the deep sea.With the rapid development of weapons and equipment in various countries,the design of submarines is also moving towards a large potential and large scale.This puts forward higher requirements for the stability of the pressure shell.However,due to the influence of initial defect and residual stress,the actual bearing capacity of pressure shell is often lower than that of ideal model.The reduced stiffness method can be used to reduce the influence of these complex conditions to the reduction of ideal structural stiffness,and obtain the structural response quickly and accurately.The stability of spherical cylindrical composite shell in submarine is studied in this paper.Several factors affecting structural stability are discussed.An experimental scheme is designed to study the instability mechanism of sphere-cylinder combined shell.The research provides a basis for the design of pressure shells and has important practical significance.Main tasks are as followsThe theoretical formula used to calculate the critical instability load of spherical pressure shell is derived.Based on the stress characteristics of the spherical structure under uniform pressure,a slat beam passing the center of the sphere is used to simplify the problem.The instability load under several structural parameters is calculated.The instability load under several structural parameters is calculated,and then a mathematical formula is used to calculate the fitting formula for the critical instability load of the spherical shell structure.The calculation method of the instability load of the cylindrical shell structure is studied.Applying the idea of reduced stiffness method,the effects of the stiffness of the shell and the rib structure on the ultimate bearing capacity of the structure are studiedThe continuous displacement function of the spherical cylindrical composite shell is established,and the critical instability load of the structure is solved.The numerical method is used to calculate the critical load of the spherical cylindrical composite shell instability under the given parameters and compare with the finite element.The influence of different types of stiffness on the critical load of sphere-cylinder combined instability is analyzed.The effects of two types of defects on structural stability are studied.Aiming at the research on the critical instability load of the sphere-cylinder combined structure in this paper,an experimental scheme is designed to investigate the instability mechanism of the sphere-cylinder combined structure.