The influence of waves and hydrodynamic interaction on energy-based evaluation of ice loads during a glancing impact in sea states

This research investigates the effect of waves and hydrodynamic interaction on the ice loads during a glancing impact between an ice floe and a ship advancing at low speed in various sea states. An extended energy-based model is proposed for the ice loads estimation, accounting for hydrodynamic interaction through added mass and wave-induced motions, where the hydrodynamic interaction is fully involved between an advancing ship and a free-floating ice floe. The influence of sea states is investigated by calculating the added mass and motions of a ship and ice floes in six degrees of freedom under different significant wave heights and peak periods. The effect of ice floe size is analyzed by using three ice floes with different diameters. The results reveal that sea waves significantly affect ice loads by altering the relative velocity between the ship and the ice floe right before the impact. Furthermore, the influence of added mass on ice load predictions is not as pronounced as the effect of wave-induced motions. This research underscores the importance of considering hydrodynamic interactions and wave conditions in the accurate assessment of ice loads, which is crucial for the design of ice-strengthened ships and for the selection of safe speed according to sea state in ice-infested waters.