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Power-law flow statistics in anisometric (wedge) hoppers
Summer Saraf1, Scott V Franklin
1Department of Physics, Rochester Institute of Technology, Rochester, New York 14623-5603, USA.
Abstract:
We find the probability for N particles to exit an anisometric (having unequal dimensions) hopper before jamming to have a broad power-law decay with exponent α = -2, in marked contrast to the exponential decay seen in hoppers with symmetric apertures. The transition from exponential to power law is explained by amodel that assumes particle motion is correlated over a distinct length scale. Hoppers with lengths larger than this length are modeled as a series of adjacent, statistically independent "cells." Experiments with apertures 27-37 particle diameters D long are well fit by a three-cell model, implying that the correlation length is ≈ 9-12D.
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