Title: Velocity fluctuations and the clogging transition

Author (Poster): Charles Thomas, University of Pennsylvania

Abstract:

Granular media clogs as it flows out of a hopper when the exit hole, D, is appropriately small. However, when the hole is enlarged, the grains will never clog: there exists a well-defined transition between these two regimes at a critical hole size Dc. We aim to characterize this transition by approaching it from D > Dc, and investigating the grain-scale behavior of the flow. We observe that the velocity distributions become more skewed as D approaches Dc and that the time scales associated with the flow unsteadiness grow.