Compaction of Anisotropic Granular Materials: Symmetry Effects
We perform numerical simulation of a lattice model for the compaction of a granular material based on the idea of reversible random sequential adsorption. Reversible random sequential adsorption of objects of various shapes on a two−dimensional triangular lattice is studied numerically by means of Monte Carlo simulations. The growth of the coverage ρ(t) above the jamming limit to its steady−state value ρ∞ is described by a pattern ρ (t) = ρ∞ − ρEβ[−(t/τ)β], where Eβ denotes the Mittag−Leffler function of order β ∈ (0, 1). For the first time, the parameter τ is found to decay with the desorption probability P− according to a power law τ = A P− −γ. Exponent γ is the same for all shapes, γ = 1.29 ± 0.01, but parameter A depends only on the order of symmetry axis of the shape. Finally, we present the possible relevance of the model to the compaction of granular objects of various shapes.
Dragan P. Uskokovic, Slobodan K. Milonjic and Dejan I. Rakovic
L. Budinski-Petković et al., "Compaction of Anisotropic Granular Materials: Symmetry Effects", Materials Science Forum, Vol. 518, pp. 355-360, 2006