Co-Simulation Study on Ship–Ice Load and Resistance Characteristics of an Elastic Hull in Irregular Ice Fields

To overcome the limitations of existing ship–ice interaction simulations—namely, oversimplified ice floe geometries and single-field coupling schemes—this study develops a numerical framework that integrates parametric modeling with multi-physics coupling. The framework is used to investigate the effects of irregular ice floes, accounting for secondary fracture, on ice resistance and local ice loads experienced by polar vessels. A two-way coupled CFD–FEM approach is adopted, in which computational fluid dynamics (CFD) resolves the turbulent flow field around the ice-infested region, while the finite element method (FEM) analyzes the dynamic structural response of the ship hull. A non-uniform ice floe model is constructed using a Voronoi diagram algorithm based on natural ice field data and is further discretized via the discrete element method (DEM). The parallel bond-fracture criterion is incorporated to simulate collision-induced fragmentation, enabling dynamic interactions among the hull, the surrounding fluid, and broken ice. Parametric analyses are conducted considering varying ship speeds, ice floe sizes, and ice concentrations. The results reveal the dynamic characteristics of ice loads, the mechanisms underlying ice resistance enhancement, and the effects of localized stress concentration. These findings offer valuable insights for optimizing ice load protection design and improving the navigation safety of polar vessels.