Metrikin I.,Norwegian University of Science and Technology |
Loset S.,Norwegian University of Science and Technology |
Jenssen N.A.,Kongsberg Maritime Kongsberg |
Kerkeni S.,DCNS S.A.
Marine Technology Society Journal | Year: 2013
Numerical simulation of dynamic positioning (DP) in ice is a novel research topic that has potential in many industrial and scientific applications. This paper reviews some challenges associated with numerical ice modeling and presents a classification of approaches formodeling the ice loads in DP simulations. The approaches are classified into three groups: empirical and statistical models, experimental data series methods, and physically based modeling. The strengths and weaknesses of the approaches are summarized, and recommended uses are outlined in this paper. In addition, a novel, nonsmooth, discrete element model of a DP vessel in managed ice is presented. Themodel was used to perform a numerical multibody simulation of a series of model tests with a conceptual Arctic drillship on DP in managed ice using the commercial physics engine Vortex. The numerical model simulated the ice basin, the DP vessel, the managed ice, the surrounding fluid, and their interactions. Comparison of the simulation results with experimental data showed that for head-on ice drift, the numerical model reproduced the experimental results reasonably well. However, for higher ice drift angles, discrepancies between the simulation results and the model testing data increased considerably. Possible reasons for the discrepancies are discussed in the paper, along with suggestions for future research. To the best of the authors' knowledge, both the classification of various approaches for simulating DP in ice and the high-fidelity numerical DP model are novel and have not been published previously.