ABSTRACT
Some theoretical models of compaction dynamics (Arenzon & Levin 2003) are based on a relationship between the mobility µ of the grains and the packing fraction ρ. The mobility is a local property of each grain that corresponds to the grain ability to move in its nearest neighborhood inside the packing. The mobility is assumed to vanish when the packing fraction ρ reaches its asymptotical value ρ∞. Boutreux and de Gennes (Boutreux & de Gennes 1997) argued that the logarithmic compaction dynamics (Eq.(2)) is related to the Vogel-Fulcher law
where c represents some decay rate of the grain mobility near ρ∞. The Vogel-Fulcher (3) law was derived from a Poisson distribution of voids in the system.
