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arXiv · 0708.3491

Equation of State of Wet Granular Matter

A. Fingerle·S. Herminghaus
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Abstract

A theory is derived for the nonequilibrium probability currents of the capillary interaction which determines the pair correlation function near contact. This yields an analytic expression for the equation of state, P = P(N/V,T), of wet granular matter for D=2 dimensions, valid in the complete density range from gas to jamming. Driven wet granular matter exhibits a van-der-Waals-like unstable branch at granular temperatures T > T, is of relevance for aggregation in general, simulations have been performed which show very good agreement with the theoretically predicted coordination K of capillary bonds as a function of the bond length s_crit. This result implies that particles that stick at the surface, s_crit=0, form isostatic clusters.

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A. Fingerle, S. Herminghaus. 2007-08-27. Equation of State of Wet Granular Matter. https://doi.org/10.1103/physreve.77.011306

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