Heterogeneous dynamics of a granular pack under vertical tappingS. Kiesgen de Richter, G. Le Caër and R. Delannay
Institut de Physique de Rennes - UMR UR1-CNRS 6251, Université de Rennes 1, Bât. 11A, Campus de Beaulieu 263 av. Général Leclerc, 35042, Rennes Cedex, France, EU
received 1 December 2008; accepted in final form 11 February 2009; published March 2009
published online 18 March 2009
The dynamics of a tri-dimensional dense granular packing under gravity and vertical tapping is numerically investigated in a stationary state. A slowing-down of the dynamics is observed close to the bottom of the packing with a correlation length of 5–6d. In this perturbed zone, the self-intermediate scattering function, decaying slower than exponentially, suggests the existence of a heterogeneous dynamics. A characteristic time scale of the dynamics depending on the distance from the bottom of the packing is extracted. Our numerical results open the way to a systematic study of the influence of external driving force and of boundary conditions on the heterogeneity of the dynamics of granular packings under gravity.
83.80.Fg - Granular solids.
05.40.-a - Fluctuation phenomena, random processes, noise, and Brownian motion.
45.70.Cc - Static sandpiles; granular compaction.
© EPLA 2009