Compacity influence in reorganization of two dimensional granular packings: Numerical model

Rearrangements (movements of disks) of different sizes are observed before the avalanche onset while studying avalanche process in 2D packings of disks of diameter d. A stochastic cellular automata model based on experimental observations is proposed to understand the influence of local packing fraction in the appearance of rearrangements in a two dimensional packing of disks. In numerical simulations, rearrangements of different sizes are also observed and evolution of the packing fraction is studied. The cellular automata retrieves experimental results when it considers a range of influence for rearrangements larger than 9d. Rearrangements are also found to be responsible for the decreasing of the system global packing fraction in discrete steps.