A calibration‐less, bonded‐sphere model for highly deformable particle systems in a discrete element method framework

Here, we introduce a calibration‐less bonded‐sphere model to describe three‐dimensional, linear elastic, highly deformable particles. Voronoi tessellation is used to partition a particle into multiple sub‐spheres, generating a virtual bond network that mimics the mechanical properties of the original particle. Inter‐particle collisions are resolved by considering contacts between the contacting sub‐spheres. The model is validated through six test cases: (i) bending of a beam, (ii) stretching of a rod, (iii) contact of a deformable sphere with a flat wall, (iv) collision between two deformable spheres, (v) motion of a deformable sphere along an inclined plane, and (vi) packing of deformable spheres. The results confirm that the desired mechanical properties of the deformable particle (i.e., Young's modulus and coefficient of friction) are obtained when assigning the desired values to the virtual bonds and the sub‐spheres comprising the bond network, thereby omitting a tedious calibration process typically required by conventional bonded‐sphere models.