A Study on Viscous Wave Drift Force on Semi-submersible and Prediction of The Extreme Value of Mooring Force

Kazuhiro Yukawa, Shunji Kato
2019 Journal of the Japan Society of Naval Architects and Ocean Engineers  
In 2012, a mooring line of the semi-submersible" Deepsea Atlantic "that had been operating at Gullfaks South Field in the North Sea was broken. A JIP team investigated causes of the accident in Norway and reported that the accident occurred due to the combination of viscous wave drift force and anomalous wave. Until now, potential wave drift force has been used in the mooring design for semi-submersible but viscous wave drift force has not been taken into consideration. Generally, in the
more » ... cy band where the wave length is long, the ratio of potential wave drift force is small among wave drift forces acting on the floating body, while viscous wave drift force becomes dominant. In a structure of which splash zone has a short diameter, such as a column of semi-submersible, the wave length is long compared to the column, and the viscous wave drift force acts remarkably.
doi:10.2534/jjasnaoe.30.59 fatcat:jakbyhiqe5enrbzh52dxx42v7y