Boussinesq-Hydroelasticity coupled model to investigate hydroelastic responses and connector loads of an eight-module VLFS near islands in time domain

Abstract

When a very large floating structure (VLFS) is deployed not far from the shore line or near the island, the ocean waves and hydroelastic responses of VLFS could be greatly influenced by the complicated topography and inhomogeneous wave. Based on the Boussinesq equation and Cummins’ theory, a three-step time-domain hydroelastic method for VLFS on depth-varying seabed and inhomogeneous waves is established, called Boussinesq-Hydroelasticity coupled method. An eight-module semi-submersible VLFS is studied for numerical assessment using RMFC (rigid module flexible connecto) model; meanwhile, the wave evolution simulation is carried out based on Boussinesq equation. The motions of each module and connector loads are investigated by considering the depth-varying seabed and inhomogeneous wave. Furthermore, the model test is carried out in wave tank for validating the correctness of the numerical results and the Boussinesq-Hydroelasticity coupled method. There is significant shelter effect on the floating bodies arranged behind the island. When the water depth is assumed to be constant by ignoring the influence of seabed topography, the load of connectors will be underestimated.