Offshore Platform Fluid Structure Interaction Simulation

Abstract

In this study a one-way coupled fluid-structure interaction (FSI) between ocean waves and a simplified offshore platform deck structure was modeled. The FSI model consists of a Volume of Fluid (VOF) based hydrodynamics model, a structural model and an interface to synchronize data between these two. A Computational Fluid Dynamics (CFD) analysis was used to capture the breaking wave and impact behavior of the fluid on the structure using commercially available software STAR-CCM+. A 3D Finite Element (FE) model of the platform deck developed in ABAQUS was used to determine the deflection of the structure due to hydrodynamic loads. Nonlinear material behavior was used for all structural parts in the FE model. Transient dynamic structural analysis and CFD analysis were coupled by transferring the CFD-predicted pressure distribution to the structural part in each time step using the co-simulation capabilities of STAR-CCM+ and ABAQUS. The one-way FSI model was applied to investigate the possible physical causes of observed wave damage of an offshore platform deck during a hurricane. It was demonstrated that with proper physical conditions/configurations, the FSI model could reproduce a structural deformation comparable to field measurement and provide valuable insight for forensic analysis.