Hydrodynamic Response of a Large-Scale Mariculture Ship Based on Potential Flow Theory

Abstract

The marine fishery will be the main form of the marine economy in the future. Simulating a hydrodynamic response under normal and extreme working conditions is the main means of structural analysis and design of a mariculture ship. In this paper, a simulation methodology is proposed based on potential flow theory, focusing on a semi-submersible large-scale mariculture ship with a rigid frame. Abaqus/Aqua 2020 software is used to establish a full-scale dynamic analysis model of the fishery. In the simulation, a nonlinear implicit integration method is applied, and the non-deterministic boundary conditions of the floating body are optimized using dynamic equilibrium principles. By varying the wave and flow conditions, the variations in mooring forces, vibration amplitudes, and average vibration values are analyzed. Furthermore, the dynamic changes in the overall spatial displacements of the fishery, characteristics of longitudinal and vertical oscillations, and mid-span deflections are analyzed. It is concluded that the mooring force is linearly correlated with the flow velocity, that a higher wave increases the longitudinal oscillation amplitude, and that a longer wave period leads to higher mooring forces and longitudinal heaving amplitude. These dynamic response and displacement results of the mariculture ship are expected to provide a basis for its design and safety assessment.