Numerical investigation of propeller-ice interaction effects

An innovative numerical tool has been developed to assess the effects of propeller-ice interaction on the loads acting on the propellers. The loads are calculated as the sum of the separable hydrodynamic loads, the inseparable hydrodynamic loads and the ice contact loads. The separable hydrodynamic loads are the loads acting on the propeller in ice-free water whereas the inseparable hydrodynamic loads act on the propeller due to the ice blockage effect. Both of these loads are calculated by a panel based code. The ice-contact loads, i.e. the loads originating from the physical contact between the ice particles and the propeller, have a significant contribution to the total loads acting on the propeller and are calculated using the empirical formulae. The calculated loads are transferred to a commercial Finite Element Solver that calculates the stresses and strains developed by the said loads across the propeller blades. Several interaction scenarios are modeled & compared, and the effect of various parameters is quantified. The simulation tool is calibrated based on the results from a model test campaign in which a linear feeding device is used to guide ice floes into a rotating model propeller to be milled under controlled conditions.