Second Order Model for Wave Crests Used in Prediction of Green Water Load and Volume on Ships in Random Waves

Abstract

The probability that a wave crest in a random sea will exceed a specified height has long been recognized as important statistics in practical work, e.g., in predicting green water load and volume on a ship. Nonlinear probability density functions for predicting green water load and volume are presented. The models are based on the parametric model of (2003, “Long-Term Prediction Method for the Green Water Load and Volume for an Assessment of the Load Line,” J. Marine Sci. Technol., 7, pp. 137–144) combined with transformation of a second order wave crest height model. The wave crest height model is obtained from second order wave theory for a narrow-banded sea state in combination with transformation of the Rayleigh distribution. Results from the second order models are compared with model tests of a cargo ship presented in (2003, “Long-Term Prediction Method for the Green Water Load and Volume for an Assessment of the Load Line,” J. Marine Sci. Technol., 7, pp. 137–144) and the Ogawa models.