Comprehensive numerical study on the behavior of floating structures under challenging ocean conditions using WCSPH

Abstract

The main objective of this study is to investigate the dynamic motions of floating bodies under different wave conditions. A particle-based numerical method, Smoothed Particle Hydrodynamics (SPH), is used due to its capabilities in modeling violent free surface flows. This work is based on five sub-steps. The first step focuses on ensuring the accuracy of the generated wave characteristics. Then, the heave motion of a point-absorber wave energy converter is examined under regular wave conditions with different power take-off (PTO) damping coefficients. After validating the proposed SPH scheme in a single degree of freedom motion, the roll decay of a rectangular floating body is investigated in the third step by comparing natural frequencies and damping coefficients with available literature data. Subsequently, the roll motion of a fixed floating structure under a wide-range regular wave system is simulated to obtain the corresponding Response Amplitude Operators (RAOs). Finally, the free body motion of a floating body under regular wave excitation is simulated and validated by experimental measurements, considering all rotational and translational motion characteristics. In the light of all simulation results, the proposed SPH numerical scheme can be considered as a useful tool for the design of effective and sustainable offshore structures.