Hydrodynamic Decomposition-Based Optimization of Ship's Hull-Propeller System Under Multiple Operating Conditions

In this research, a framework for the analysis and design optimization of ship hull-propeller systems (HPSs) in waves is developed. This framework can be utilized as an efficient synthesis tool to determine the main geometric characteristics of the HPSs during the early stage of ship design. The optimization is carried out in two levels and under multipoint operating conditions (OC). Multiobjective evolutionary algorithm based on decomposition (MOEA/D) as an efficient multiobjective evolutionary algo-rithm, Michell integral and OpenProp tool as low-fidelity hydrodynamic solvers and boundary element method (BEM) as medium-fidelity solver are applied on two case studies to minimize the effective power and maximize the propulsive efficiency of HPSs. To estimate the added wave resistance, an efficient semiempirical formula is also employed. The Series 60 hull form with DTMB P4118 single propeller and S175 hull form with KP505 twin-propeller are considered as the original models. The numeri-cal results show that the framework can find optimized designs with better hydrody-namic performance.