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Wind load is one of the major design loads for the hull and mooring of offshore floating structures, especially due to much larger windage area above water than under water. By virtue of extreme design philosophy, fully turbulent flow assumption can be justified and the hydrodynamic characteristics of the flow remain almost constant which implies the wind load is less sensitive to the Reynolds number around the design wind speed than wind profile. In the perspective of meteorology, wind profile used for wind load estimation is a part of Atmospheric Boundary Layer (ABL), especially maritime ABL (MBL) and have been studied how to implement the profile without losing turbulence properties numerically by several researchers. In this study, the MBL is implemented using an open source CFD toolkit, OpenFOAM and extended to unstable ABL as well as neutral ABL referred to as NPD profile. The homogeneity of the wind profile along wind direction is examined, especially with NPD profile. The NPD profile was applied to a semi-submersible rig and estimated wind load was compared with the results from wind tunnel test.

Mean wind load on a semi-submersible rig and an FPSO was investigated by using Computational Fluid Dynamics (CFD) for the modeling practice developed in Reproducible Offshore CFD JIP. The modeling practice is benchmarked against available model test results for a semi-submersible rig and an FPSO in blind manner between verifiers. For the semi-submersible rig, an even keel and four inclined conditions were considered. The uncertainty levels between verifiers’ results were within 10%. Slightly larger scatter was observed in inclined conditions but did not show any larger than 10%uncertainty level. It was possible to reduce the discrepancy by easing the setting difference from the wind tunnel test by introducing gap around deckbox and columns. For the FPSO, the results were within 3%for forces and within 14%for moments. After considering model test setup including the gap between FPSO hull bottom and turntable, the results were improved and within 10%error between the results and wind tunnel test except for 120 and 240° headings.

A numerical study is made of heat transfer characteristics from pulsating flow in a concentric annutus partially filled with porous media. The unsteady Navier-Stokes equations with the Brinkman-Forchheimer-extended Darcy model in the porous region art solved by using finite volume techniques. Changes in connective heat transfer and in effective anal heat conduction due to pulsation are investigated over broad ranges of the relevant parameters, i.e., the thickness of the porous layer and the frequency and amplitude of pulsation. The results obtained indicate that the effective axial thermal conductivity is substantially increased by pulsation, and this augmentation is more pronounced by partial fillings of porous material