Research On Optimum Design Of A Container Ship Based On Response Surface Methodology

Along with the fast growth of global trade, the container transportation with the characteristic of high efficiency and convenience gradually seizes the market and becomes the mainstream of shipping industry .As a result of larger hatch opening of container ship, ship structure destroy on the basis of torsion has become the main factor of container ship structure destroy. So how to optimize its structure design to enhance its economy under the strength demand has been the main focus of the shipbuilding research.In order to analysis the torsion characteristics of container ship more efficiency, more reasonable and more convenient; this paper introduced the conception of response surface method to simulate the state of stress in the condition of pure torsion. The finite element model of container ship for sensitivity analysis selected the exact independent variables, and then using the Orthogonal-Test-Design method for simulating mechanical behavior of container ship to build a maximum stress quadratic function with independent variables of thickness of side plates, thickness of inner hull, thickness of bottom plating, thickness of deck stringer plates, height of double bottom and width of double side.An initial research on structural optimization design of holistic cargo tank of container ship based on response surface methodology is accomplished in this paper. Pursing minimum structure weight, identify design variables deciding weight; according to Rules for Building and Classing Steel Vessels and Guidelines for Direct Calculations of Strength of Container Ships, identify response surface function of stress and dimensions of identify design as constraint condition. The problem of nonlinear constrained optimization is solved by combination of penalty function method and the branch and bound method. Finally, the feasibility and reliability of the method are proved with the structural optimum design of the 700TEU container ship. The results of optimization show that the weight of transverse cargo tank decreases by 7.34%.