A Numerical Model for the Elasto-Plastic Behavior of Cellular and Granular Materials

Abstract We present a 2D numerical model for simulating soft deformable cells and particles. To allow large deformations, the particle boundary is represented by an array of elements interacting at their nodes through elasto-plastic force laws governing their linear and angular relative displacements. Thus, the particle shape change is controlled by a combination of boundary stiffness and an internal particle pressure, which is coupled with the particle volume through a bulk modulus. The model is verified by comparing the results of our simulations of single particle deformation under load with theoretical predictions. We also showcase the potential power of our model in application to packings of particles involving both large particle shape change and dynamic rearrangements such as the compaction of a granular assembly of ultrasoft particles or the fracture of plant cell tissues.