Model Experiment on Heel-Induced Hydrodynamic Forces in Waves for Realising Quantitative Prediction of Broaching

Abstract

Mathematical models for capsizing due to broaching, one of the great threat to ships running in following and quartering seas, have been developed by many researchers. However these models can predict it only qualitatively. For realising quantitative prediction, we conduct the systematic captive model experiments with the large heel angles up to 50 degrees in severe following waves. As a result, the details of nonlinear heel-induced hydrodynamic forces with respect to heel angle in waves are presented. Then the comparisons between a free running model experiment and the numerical simulation with direct use of the measured heel15 induced hydrodynamic forces are carried out. As a result, the mathematical model for realising quantitative prediction of broaching in severe following and quartering seas is presented. Finally the simplified mathematical model is also proposed for more practical uses with less experimental efforts.