A Computational Fluid Dynamics Study on Dynamic Performance Characteristics of a Semi-Displacement Ship (DC372) Under Varying Weight Distributions

This study investigates the influence of longitudinal center of gravity (LCG) and pitch moment of inertia (Iyy) on the dynamic performance of a DC372 semi-displacement ship, focusing on motion responses and added resistance in different wave conditions. Using OpenFOAM’s two-phase RANS-VOF solver, five weight distribution scenarios were simulated in both calm water and regular waves, with a wave amplitude of 0.02 m and wavelength-to-ship length ratios (Lw/Ls) ranging from 0.6 to 1.5. The results demonstrate that a 10% aftward shift in LCG significantly reduces heave and pitch response amplitude operators (RAOs) by 18% and 12%, respectively, at Lw/Ls =1. Additionally, a 30% reduction in Iyy leads to a 22% decrease in added resistance, highlighting the critical role of mass distribution in hydrodynamic efficiency. These findings provide valuable insights for optimizing hull design to enhance seakeeping performance, minimize fuel consumption, and comply with International Maritime Organization (IMO) emission regulations. The study underscores the importance of computational fluid dynamics (CFD) in ship design for improved sustainability and operational efficiency.