Simulation of Ship-wave-ice Interactions in the Arctic

Global climate change is presenting opportunities for new networks of maritime transportation through the Arctic. However, these sea routes are often infested by floating sea ice, which brings uncertainties to shipping operators, designers and builders. This work aimed to develop reliable simulation approaches for shipping scenarios in the presence of sea ice and investigate the associated changes to ship calm water resistance. For this purpose, computational fluid dynamics and ice solid mechanics were combined to model the potential ship-wave-ice interactions. Specifically, models were developed to simulate the two primary scenarios of a cargo ship operating in the Arctic, respectively a waterway with floating ice floes and an open-water channel created by icebreakers. Additionally, to build understanding of the Arctic sea condition, two other models were developed simulating the interaction of ocean waves with a rigid ice floe and then an elastic ice sheet, which provided a new solver capable of modelling hydroelastic fluid-structure interactions. Based on validation against experiments, these models provided the ability to accurately predict the ship-wave-ice interactions and the ice-induced resistance changes. Through conducting a systematic series of simulations, it was found that ice floes can increase the ship resistance by the same order of magnitude as the open water resistance, but this is strongly dictated by the ship beam, ice concentration, ice thickness and floe diameter. An open-water ice channel was found to increase the ship resistance by up to 15% compared to the situation without ice, particularly when the channel width is less than 2.5 times the ship beam and the ice thickness is greater than 5% of the ship draught. Moreover, this work developed a procedure to derive simple ice-resistance equations from the simulation results, enabling fast prediction of ship fuel consumption in sea ice fields and incorporation into a new Arctic Voyage Planning Tool