Numerical wind load estimation of offshore floating structures through sustainable maritime atmospheric boundary layer

• Published in: International journal of naval architecture and ocean engineering Vol. 12; no. 12; pp. 819 - 831
• Main Authors: Yeon, Seong Mo, Kim, Joo-Sung, Kim, Hyun Joe
• Format: Journal Article
• Language: Korean
• Published: 2020
• Subjects: OpenFOAM; NPD; Offshore floating structures; Atmospheric Boundary Layer (ABL); Maritime ABL (MBL)
• ISSN: 2092-6782; 2092-6790

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.