Effect of grain anisotropy on ordering, stability and dynamics in granular systems
Theoretical and Applied Physics Divisions, Los Alamos
National Laboratory Los Alamos, NM 87545, USA
2 Department of Physics, University of California - Davis, California 95616, USA
Accepted: 2 January 2002
With experiments and simulations, we show that monomer, dimer, and trimer beads in 2D represent an ideal system in which specific types of order, dynamics, and granular stability can be controlled. We determine the distinct types of ordering for increasing grain anisotropy. Dimers possess a quasi-ordered state in which translational but not orientational order exists, while trimers are disordered. We show that these different orderings give rise to specific types of flow. Monomers show a large-scale collective ordered shear motion, dimers show tumbling motion near the surface, and trimers show disorderly bulk tumbling.
PACS: 81.05.Rm – Porous materials; granular materials / 45.70.-n – Granular systems / 45.50.-j – Dynamics and kinematics of a particle and a system of particles
© EDP Sciences, 2002