A numerical model for real-time simulation of ship-ice interaction

A ship advancing in level ice will introduce several failure processes to the ice sheet, such as localised crushing and breaking due to bending stresses. The resulting ice fragments will interact with each other, with water and with the hull of the ship. They may rotate, collide, or slide along ship's hull, and eventually they will be cleared away. The situation is different in a broken ice field, i.e., large ice floes may behave similar to level ice while smaller floes will mostly be pushed aside, rotated or submerged. Modelling of such a complex system is very demanding and often computationally expensive which would typically hinder the chances for real-time simulations. This kind of simulations can be very useful for training personnel for Arctic offshore operations and procedures, for analysing the efficiency of various ice management concepts and as a part of the onboard support systems for station keeping. The challenge of meeting the real-time criterion is overcome in the present paper. The paper describes a numerical model to simulate the process of ship-ice interaction in real-time. New analytical closed form solutions are established and used to represent the ice breaking process. PhysX is used for the first time to solve the equations of rigid body motions in 6 degrees of freedom for all ice floes in the calculation domain. The results of the simulator are validated against experimental data from model-scale and full-scale tests. The validation tests exhibited a satisfactory agreement between the model calculations and experimental measurements. (C) 2010 Elsevier B.V. All rights reserved.