A TIME-DOMAIN COMPUTATION METHOD FOR DYNAMIC BEHAVIOR OF MOORING SYSTEM

A quasi-steady time domain method is developed for the prediction of d ynamic behavior of a mooring system under the environmental disturbanc es, such as regular or irregular waves, winds and currents. The moorin g forces are obtained in a static sense at each instant. The dynamic f eature of the mooring cables can be obtained by incorporating the exte nded 3-D lumped-mass method with the known ship motion history. Some n onlinear effects, such as the influence of the instantaneous change of the wetted hull surface on the hydrostatic restoring forces and Froud e-Krylov forces, are included. The computational results show a satisf actory agreement with the experimental ones.