Prediction of Parametric Rolling in Irregular Head Waves

For providing a benchmark data for numerical codes of parametric rolling prediction, a model experiment of a post-Panamax C11 class containership whose hull form is slightly modified from its original but opened for public was conducted and significant parametric rolling in irregular head waves was recorded. The existing numerical model developed by the authors for parametric rolling in regular longitudinal waves was extended to be applied to irregular longitudinal waves. Comparisons between the model experiment and the numerical result show reasonably good agreement under consideration of dispersion due to practical non-ergodicity. By utilizing the developed numerical model, it was demonstrated that small height of the bilge keel is a main reason why significant parametric rolling could happen for the C11 class post-Panamax containership.