Some recent fluid-structure interaction approaches for the wave current behaviour with offshore structures

Abstract

The effects of the surface waves generated by the wind have a significant effect on the currents. A wave current coupled model plays an important role in the design offshore structures. The interaction between fluids such as incompressible ocean waves and current and offshore structures is significant with many real-time applications in offshore engineering. These coupled models can be applied to Offshore Floating Production Operating and offloading (FPSO), Wind or current turbines and offshore pipelines. The complex issues related to the design are analyzed by using Computational Fluid Dynamics, which requires an investigation of the multiphase flow between wave and current and the structure which is considered restrictive due to the computational cost. If viscous effects are neglected then the single-phase flow models have been recommended, where wave-current interaction have been modelled successfully. Models have been developed where velocities and pressure are computed and the results can be verified with the experimental results available in the literature. In this study the existing numerical methods, mesh types are discussed along with their coupling methods. Here single-phase and multiphase models with small and medium movement are reviewed and their applications are highlighted. Commercial CFD code ANSYS Fluent has been found most reliable and easy to use tool for the analysis of fluid flow interacting with offshore structures near the free surface. It can successfully be used for determination of fluid dynamics of offshore environments installed complex multi-component structures. Dynamic mesh facility is more useful for multiphase modelling of floating structures.