Numerical Evaluation of Wind Loads on Semi-Submersible Platform by CFD

A numerical study of wind loads on a semisubmersible platform is presented on this paper. The techniques of Computational Fluid Dynamics (CFD), such as Reynolds Averaged Navier-Stokes Equations (RANS) model and Large Eddy Simulation (LES), etc., were adopted in this study to predict wind loads on and wind flows around the platform. The main objective of this study is to explore an effective and reliable approach for evaluation of wind loads on offshore structures by CFD methods. The computed results were compared with experimental data which obtained at wind tunnel test. It was found through the comparison that the LES with a dynamic sub grid-scale (SGS) model can give satisfactory predictions for mean and dynamic wind loads on the tall structures. Therefore, it is necessary to correctly simulate both the incident wind velocity profile and turbulence intensity profile in CFD computations to accurately predict wind effects on huge structures. The recommend CFD techniques and associated numerical treatments provide an effective way for designers to assess wind effects on offshore platforms and the need for a detailed wind tunnel test.