Hydroelastic investigation of a multi-modular OSUS with flexible connectors using coupled CFD-FEA method

A multi-modular floating Ocean Space Utilization Structure (OSUS) with flexible connectors is adopted and analyzed in this paper. A fluid-structure interaction (FSI) model which strongly couples computational fluid dynamics (CFD) and finite element analysis (FEA) solvers is proposed to simulate module motions, structural loads at the connectors, and water resonance within the inner basins of the OSUS under regular wave conditions. The present model is effective in evaluating the overall deformations of the broad-shallow floating OSUS, as well as the six-degree-of-freedom structural loads at the sectional connectors. Both the wave modeling and the FSI framework have been independently validated, showing good agreement with other numerical results and experimental data. The results reveal complex coupled vertical and torsional vibration modes in the OSUS. The hydroelastic responses exhibit strongly nonlinear behavior, and water resonance is related to vertical heave motion. The connectors are subjected to considerable structural loads, especially in terms of axial force, vertical shear force, torsional moment, and vertical bending moment. The conclusions drawn from this study provide valuable insights for optimizing connector design and improving the seakeeping performance of such broad-shallow floating OSUSs, offering practical guidance for future engineering applications.