Hydrodynamic analysis of a modular multi-purpose floating structure system with different outermost connector types

The present work investigates the effect of different outermost connector types on the hydrodynamic responses of a modular multi-purpose floating structure (MMFS) system. The MMFS system is preliminarily designed for a mild sea zone, which is composed of a number of standardized floating modules. In this study, the MMFS system has been simplified as a seven-module connected system. Considering the structural deformation of the MMFS system mainly occurs in the connectors among adjacent modules, each module is viewed as a rigid body. Both the hydrodynamic interaction effect and mechanical coupling effect among modules have been taken into consideration in the time-domain analysis. Different outermost connector designs have been proposed and investigated for the MMFS system. The results indicate that the hydrodynamic responses of the MMFS system are sensitive to the effects of the connector types, the wave phase, and the wavelength. The hinge-type design of the outermost connector can significantly reduce the extreme responses of both the bending moment and the shear force of the connectors. The additional PTO damper design for the outermost hinge-type connector can effectively reduce the motion of the outermost module, and also produce considerable wave energy.