Predicting wind loads on single vessels and in side by side offloading configuration for FPSO and shuttle tanker using CFD

AuthorsYoo, D., Park, J., Schrijvers, P., Koop, A.
Conference/JournalThe 28th International Ocean and Polar Engineering Conference (ISOPE), Sapporo, Japan
DateJun 10, 2018
This paper presents the results of the wind loads on typical offshore vessels at model scale 1:250 obtained with CFD simulations. A FPSO, shuttle tanker and two membrane/moss type LNG carriers have been investigated, as well as the side-by-side configuration of FPSO and shuttle tanker with a gap of 4m. The results are compared with the wind tunnel tests carried out within the Offloading Operability 2 JIP. The CFD code ReFRESCO is used. In this study, the simulations are carried out as a steady state problem and the k- SST model is used as turbulence model.

In order to efficiently solve every incidence angle from 0 to 360 with 15 degrees intervals, a cylindrical numerical domain is used. The numerical uncertainty has been determined using four consecutively refined grids. The results for the FPSO, shuttle tanker and membrane LNGC show a good agreement with experiments. For these vessels, the flow separation point is geometrically defined. The moss type LNGC is more difficult to compute accurately since the separation points on hemispherical tanks are difficult to capture.

The side-by-side configuration with the FPSO and shuttle tanker has 4m gap between the vessels. The calculated coefficients agree well with the experiments and the overall trends are nicely captured, except for a slight deviation for the yaw moments from 135 to 180 degrees. From the results presented in this paper, we conclude that the wind loads on offshore vessels in side-by-side configuration can be predicted with reasonable accuracy with CFD.
Tags
manoeuvring and nauticalstability, seakeeping and ocean engineeringcfdmanoeuvringoffshore operationspassengers and yachtingcfd/simulation/desk studies