Peridynamic modeling of polycrystalline S2 ice and its applications

• Realize the anisotropic characterization of 2D ice single crystal by peridynamics. • Establish an accurate mesoscale model of 2D polycrystalline columnar ice. • Obtain the minimum grain number of S2 polycrystalline ice to maintain macroscopic isotropy is 225. • Study the mode I fracture characteristics of polycrystalline ice plate. We investigate the numerical modeling method of columnar polycrystalline ice based on peridynamics. A polycrystal with relatively uniform area is established with the Voronoi method to model the mesoscale polycrystalline behavior of S2 columnar ice. The grain orientations are given by the uniform random algorithm, and the characterization of grain anisotropy is realized with a nonspherical influence function. The correctness of the anisotropic characterization method is verified by monitoring the displacement of specific points. A macro homogenization analysis of multiple groups of polycrystalline ice models is conducted by applying periodic boundary conditions, and the equivalent parameters are analyzed comprehensively. Finally, the minimum number of grains required to maintain the isotropy of polycrystalline ice is determined to be 225. The mode I tensile fracture of a polycrystalline ice plate is simulated with the abovementioned numerical method and a critical tensile criterion, and the tensile strength range is obtained. These results closely agree with existing results, indicating that the current method can accurately characterize of polycrystalline materials and enable polycrystals with sufficient grain numbers to stably express isotropy at the macroscale, which is applicable to multiscale research on polycrystalline materials.