CFD and experimental assessment of green water events on an FPSO hull section in beam waves

Abstract CFD prediction of water on deck and impact on a deck structure is investigated and results confronted to those obtained in a wave flume. A simplified set-up is employed, consisting of a model of an FPSO section fixed in the flume, emulating its interaction with regular beam waves. The influence of a riser balcony is also considered. The aim is to focus the investigation on the ability to reproduce the dynamics of the water shipping on FPSOs. In addition, the tests in regular waves allowed an evaluation of variations from cycle to cycle, making the apparent randomness of the maximum impact loads more evident. An analysis is made on the main factors that control these variations and how they are affected by changes in the wave parameters. Apart from the variability, results show that the CFD simulations were generally able to predict the statistical maxima with sufficient accuracy, even for situations with large volumes of water on deck. Even though the discrepancies on the force maxima rise for the steepest waves, results attest that the force impulses remain accurate.