Calculation Method Of Shell Strength And Stability Of Symmetrical Bi-Cylindrical

In this paper, a new pressure structure of submarine is presented. The symmetrical bi-cylindrical structure is a closed shell composed by two unclosed arch shell. There is a vertical waterproof longitudinal bulkhead between the two shell-junctures, it reinforced by some stiffener. We want to control the radial rigidity by adjusted the structural parameter, so that the mechanical capability of the new structure would be similar to cylindrical shell.The calculation method of Shell Strength and Stability of the new submarine structure is developed in this paper , based on the classic elasticity mechanics and general solution of the ring-stiffened cylindrical shell.Firstly, This paper deals with a study of radial deflection of circle arch under hydrostatic pressure, and connected it with the deflection of circular ring (pR2/Et) by a radial-deflection parameter X . The influence upon λ by the change of structure parameter is also discussed.Secondly, the analytical expression of shell stress is obtained by solving the differential equation amended by parameter A . In ideal condition the symmetrical bi-cylindrical structure have some obvious merits in strength according to the solution.Thirdly, the stability of circle arch under hydrostatic pressure is discussed and the conclusion is that the stability of arch can be effectively increased by decreasing the degree of freedom at boundary.Finally, the analytical expression of shell critical load of ring-stifffenedsymmetrical bi-cylindrical is obtained by Ritz method. The critical load of the new structure may very close to even great than the critical load of cylindrical shell.