Rule-Base Optimized Design of the Stiffened Cylindrical Shell

Pressure hull of the submarines are designed based on the classification society rules and regulations. GL is one of the classification societies which has published a complete set of the rules related to design of submarines. Using this set of rules and optimization can lead to a light weight structure with sufficient strength. Therefore، in this paper the cylindrical shell of submarines with different nominal depth are designed. This procedure includes a optimization problem with nonlinear constraints and objective function. The design variables are pressure hull thickness، stiffeners span، stiffeners web thickness and height and stiffeners flange thickness and width. The constraints are derived from GL Rules to ensure the strength of the shell. The objective function is the weight of the cylindrical shell per unit length.