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arXiv · 0811.4126

Cooling and aggregation in wet granulates

Stephan Ulrich·Timo Aspelmeier·Klaus Roeller·Axel Fingerle·Stephan Herminghaus·Annette Zippelius
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Abstract

Wet granular materials are characterized by a defined bond energy in their particle interaction such that breaking a bond implies an irreversible loss of a fixed amount of energy. Associated with the bond energy is a nonequilibrium transition, setting in as the granular temperature falls below the bond energy. The subsequent aggregation of particles into clusters is shown to be a self-similar growth process with a cluster size distribution that obeys scaling. In the early phase of aggregation the clusters are fractals with D_f=2, for later times we observe gelation. We use simple scaling arguments to derive the temperature decay in the early and late stages of cooling and verify our results with event-driven simulations.

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Stephan Ulrich, Timo Aspelmeier, Klaus Roeller, Axel Fingerle, Stephan Herminghaus, Annette Zippelius. 2009-05-15. Cooling and aggregation in wet granulates. https://doi.org/10.1103/physrevlett.102.148002

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