Numerical simulations of ice loads on an Arctic Floater in managed ice

Abstract

Abstract During the studies of ice loads on an Arctic Floater in ice, a series of numerical simulations were carried out in an advanced ship simulator with advanced ice module. The operation of the Arctic Floater will periodically be supported by an ice management system involving also physical ice management. This paper starts with introduction to the theoretical background for the Ice model, wherein the numerical model enables modelling of the arctic floater the mooring and different managed ice conditions. The managed ice is created as convex ice floes with comparable size ice floes used in model scale tests. A number of simulations were compared with and validated against results from identical set up in ice tank tests. Based on a set of assumptions from these simulations, a series of situations with varying ice drift direction, ice drift speed, floe thickness, domain size and ice floe coverage made the input parameters to the numerical model. Ice loading on the Arctic Floater is governed by ice breaking loads and ice transport around the hull. During the numerical simulations, the movement of the Arctic Floater was studied, the forces were calculated and influence of boundary conditions was investigated. The numerical simulations gave the possibility to compare ice floe interaction with and without boundary influence of an ice tank set up. Simulations was also used to show what would happen if the Arctic Floater is hit by a large unbreakable ice floe. The results presented in this paper show good correlation with model scale results for the Arctic Floater in drifting managed ice. Results from additional simulations gave useful input for predicting ice forces and system behaviour in ice conditions beyond what is possible in an ice tank test set-up.