Application of a practical multi-objective optimization tool to hydrodynamic design of a surface combatant ship

A practical multi-objective hydrodynamic optimization tool has been developed and applied to the design of a surface combatant ship. The main components of this tool consist of a hydrodynamic module, a hull shape representation and modification module, and an optimization module. A practical design-orientated CFD tool and Bales' seakeeping ranking method are implemented in the hydrodynamic module to evaluate the wave drag and seakeeping performance. The hull shape representation and modification module is based on hull form parameters, which enables the quick generation of realistic hull forms in the course of obtaining the optimal solutions. The multi-objective genetic algorithm (MOGA) is implemented in the optimization module to produce optimal solutions that minimize wave drag and maximize seakeeping ranking at given design speeds. For the purpose of illustration, a surface combatant ship, the DTMB Model 5415, is taken as an initial hull, and the multi-objective hydrodynamic optimization tool is used to determine optimal hull forms for wave drag and seakeeping performance at given design speeds. Numerical results obtained in this study have shown that the present hydrodynamic multi-objective optimization tool can be used in the preliminary and early-stage design.