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Stretched exponentials and power laws in granular avalanching

D. A. Head·G. J. Rodgers
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Abstract

We introduce a model for granular avalanching which exhibits both stretched exponential and power law avalanching over its parameter range. Two modes of transport are incorporated, a rolling layer consisting of individual particles and the overdamped, sliding motion of particle clusters. The crossover in behaviour observed in experiments on piles of rice is attributed to a change in the dominant mode of transport. We predict that power law avalanching will be observed whenever surface flow is dominated by clustered motion.

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D. A. Head, G. J. Rodgers. 1999-01-12. Stretched exponentials and power laws in granular avalanching. https://doi.org/10.1088/0305-4470%2F32%2F8%2F007

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