A Study on Applicability of CFD Approach for Predicting Ship Parametric Rolling

New criteria for Parametric Rolling (PR) are considered in the development of 2nd generation intact stability criterion, by the International Maritime Organization (IMO). As it is well known, estimation methods of the roll damping affect the prediction of parametric rolling significantly, and most estimation approaches for roll damping are based on experiment data or Ikeda's empirical formula. When the new criteria are applied in the design stage of ship, the accuracy of estimation approach for roll damping will be a key aspect of the validity of prediction. In this research, a hybrid method is proposed that 3D CFD approach is utilized to calculate the roll damping, while potential theory method is adopted for predicting parametric rolling motion. Furthermore, direct simulation is also investigated for PR of containership based on CFD approach. Comparative study is carried out for these two methods and potential method whose roll damping is estimated by simplified Ikeda's method and experimental data. According to the results, the CFD approach could achieve satisfactory agreements with the experiment for both roll damping and roll amplitude of PR. Therefore, CFD approach may be suitable to be utilized for PR analysis especially at the early design stage when lack of experiment data.