Optimal Design Method Research Of Submarine Structure

Submarines play an important role in modern naval power,and whether the navy equips strong submarine fleets has became an symbol of great power . After the Cold War, lots of countries although have slowed down the pace of the submarine construction, they never stop focusing on designing submarines of high performance. As an important structure of submarine, the weight and size of the hull will greatly affect the speed and stability of the submarine operation. Therefore, pressure hull structure optimization is a basic condition for the advanced performance of submarines.In this thesis, optimal design method in submarine pressure hull is researched according to the trend of submarines design. Based on the subsection optimization design spirit, the pressure hull will be divided into several typical structures to adopt different optimization strategies through the pressure hull displacement and stress finite element analysis. Two kinds of approaches for optimizing ring-stiffened circular cylindrical shell are presented. The One is combining the established approximated model with Multifunctional Optimization System Tool (MOST) to optimize the design, and the other optimization is to establish FORTRAN program with the reference of theoretical formula. Two design methods can obtain satisfactory optimization results.The optimization of the Ring-stiffened circular conical shell is to use the combined method of two different types of optimization algorithms. It not only speeds up the process of structural optimization, but also makes the results more reasonable. Hemispherical Shell is designed by using theoretical formulas under the guidance of finite element analysis. Various sections are constituted a perfect whole plane through the boundary conditions, and a strength and stability analysis have been carried out for the weak parts of the pressure hull ensuring that the optimization design is feasible and safe.The weight of the submarine pressure hull is minimized and the performance of the submarine has increased through optimum allocation of the typical structures. The research will provide the reference for the optimization design of submarine pressure hull in the future.