Abstract:The irregular granular morphology significantly affects the kinematic behavior of the granular materials in a tumbling mill, and simultaneously causes different mechanical responses of the tumbling mill. The superquadric functions were used to describe the irregular granular materials, and a discrete element method (DEM)-finite element method (FEM) coupled algorithm was developed to analyze the interaction between the irregular granular materials and tumbling mill. In this algorithm, the tumbling mill was divided into a series of quadrilateral elements, and the contact detection between the superquadric particles and the tumbling mill could be simplified as the contact detection between the superquadric particles and the quadrilateral elements. The calculated collision forces were interpolated in the nodes, which were used as the loading conditions in the finite elements for the solution of the implicit dynamics. The update of particle motion and the structural mechanical response were realized by solving the particle motion equation and the finite element dynamic equation. Furthermore, the motion behavior of spherical, cylindrical and cubic granular materials in a tumbling mill and the deformation and stress distribution of the tumbling mill were analyzed. The numerical results indicated that the particle shape significantly affected the grinding effect and structural displacement of the ball mill. The cube particles had the best grinding effect, while cylindrical particles had better grinding effect than spherical particles. In terms of structural displacement, cubic particles had the largest peak displacement, followed by the cylindrical and spherical particles. Compared to regular spherical particles, superquadric particles had irregular surface shapes, which lead to a better grinding effect and greater structural displacement.