Investigation on hydrodynamic performance of a two-module semi-submersible offshore platform

A new type of two-module semi-submersible offshore platform has been designed as an offshore floating base for scientific research and environment measurement. The platform consists of two identical configuration semi-submersible modules which are connected with hinge-like connectors. Experimental and numerical studies in both frequency and time domain were carried out to investigate the coupled behaviour of the two connected semi-submersibles with the emphasis on the motion responses of the two modules. A series of wave basin model tests for a single module and two connected modules have been conducted, and the measured data were compared with the corresponding numerical simulations which showed a good agreement. It is found that the connectors have an obvious influence on the rotational motions of the two-module platform, but little effect on the translational motions, and the present fully coupled time domain simulation model can accurately predict the hydrodynamic performance of the two-module platform.