A numerical method to simulate ice drift reversal for moored ships in level ice

This paper aims to present a new tool to simulate ice-structure interaction in 6 DoFs in time domain. The local force and global force introduced by ice as well as response of the structure are simulated. The goal is to simulate ice drift reversal case which represents the most severe conditions for level ice- hull interaction. An intact ice sheet is divided into squared ice grids and the length of each ice grid is taken as ice breaking length, which may be derived from model tests or field measurements. Both ice breaking process and ice accumulation process are included in the numerical model Based on physical observation, both bending and crushing failures are considered to calculate ice breaking force during ice interaction process. The hull waterline is updated at each time step to estimate precisely the local contact area between ice and hull. After new ice blocks fragment from intact ice, the ice rubble transport underwater and the corresponding ice rubble action on the structure are also calculated according to ISO (19906) code, where some modifications and assumptions are made to fit realistic ice-structure contact situations. The simulations are also well compared to the previous research. The result shows that the numerical tool is promising to simulate the intact ice-structure interaction.