Study of the nonlinear responses of a submersible pressure hull

Abstract

A submarine pressure hull normally experiences hydrostatic pressure at different operating depths and, during wartime, it bears shock loading produced by underwater explosions. In this study we examine the transient dynamic responses of a typical submarine hull subjected to hydrostatic pressure and shock loading, in which geometrically large deformation effects involving elastoplastic material behavior are considered. The finite element procedure based on Hibbitt and Karlsson's methodology is used to analyze the nonlinear response of the entire pressure hull. From the numerical results of a nonlinear static analysis under operating depth hydrostatic pressure, we attempt to provide the maximum operating depth at which the behavior varies from elastic to plastic. In transient dynamic analysis under shock environment, this study not only presents the elastoplastic response of the structure but also the critical region of the model. Finally, the implications of these results for future submarine design and maintenance are discussed.