Semi-Submersible Heave Response Study Using Diffraction Potential Theory with Viscous Damping Correction

Sow, C.L
Koto, Jaswar
Abyn, Hassan

Journal of Ocean, Mechanical and Aerospace -science and engineering- (JOMAse)
Vol 5 No 1 (2014): Journal of Ocean, Mechanical and Aerospace -science and engineering- (JOMAse)

This paper discusses the numerical prediction of the semi-submersible’s heave motion. In the previous study, it is observed that the heave motion response predicted by diffraction potential theory is over-estimated in the region where the heave motion is dominated by damping. In this research, viscous damping is included in the calculation to increase the heave damping magnitude in motion equation. The wave force and added mass of semi-submersible is predicted by diffraction potential theory, only the total damping is corrected by sum-up the linear damping from diffraction potential theory with the proposed viscous damping. The heave motion response obtained from the proposed numerical method also compared to the data from the experiment. From the comparison, it can conclude that involved of viscous damping in the calculation will corrected a part of heave motion response tendency and reduce the large over-predicted error of heave motion response at the damping dominate.