Modelling floating offshore units moored in broken ice: comparing simulations with ice tank tests

A numerical simulation model that simulates the behaviour of a vessel moored in broken ice has been used to compare results from numerical simulations with ice tank tests. In the simulations a tanker moored on an eight legged catenary mooring of the Submerged Turret Loading (STL) concept was towed through a broken ice field. The setup of this situation was as similar to the ice tank setup as possible. The results predicted by the model are in qualitative agreement with the experimental results, but the amplitudes tend to be overpredicted. The predicted frequency of oscillation in surge is slightly lower than what was measured. The deviations between predicted and measured results may in part be explained by the differences in model and ice tank setup, and in part by poor representation of various load limiting mechanisms. However, with the qualitative agreement achieved, and the differences between model and experimental setup in mind, it is reasonable to believe that the numerical model may yield realistic results in further full-scale simulations. (C) 1999 Elsevier Science B.V. All rights reserved.