Numerical simulation of moored ships in level ice considering dynamic behavior of mooring cable

Abstract

This study develops a new numerical method to simulate the interaction between a moored ship and level ice, taking into account the time-domain effective tension of each mooring cable. Previous studies primarily focused on the ice load exerted on the hull, with an emphasis on accurately predicting of the dynamic ice load. However, for moored structures in polar regions, the mooring system often comes into direct contact with the ice rubble formed during icebreaking process, an interaction that has been largely overlooked in existing studies. The interaction between submerged ice rubble and mooring cables significantly affects both the mooring loads and global motion of the ship. The results show that: 1) When accounting for the ice collision force on the mooring cables, both the total ice force and effective tension on key cables match the experimental data; 2) For different mooring cables, the ice collision force either decreases and increases effective tension depending on the collision angle between the cable and ice rubble; 3) The ice load on the mooring cables play a critical role, significantly impacting both the cables and the entire system. The proposed model is reliable and offers an effective, convenient method for predicting the dynamic response of mooring cables under ice collision forces.