arXiv subjects

A. Fingerle

Publications and source records attributed to A. Fingerle.

3 recordsLinked to original sources

arXiv2007

Equation of State of Wet Granular Matter

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.

cond-mat.soft↗

arXiv2007

Mechanisms of dissipation in wet granular matter

The impact dynamics between wet surfaces, which dominates the mechanical properties of wet granular matter, is studied both experimentally and theoretically. It is shown that the hysteretic formation and rupture of liquid capillary bridges between adjacent grains accounts reasonably well for most relevant cases of wet granular matter. The various dissipation mechanisms are discussed with particular emphasis on their relevance. Variations of the rupture energy loss with the impact energy are quantified and discussed.

cond-mat.soft↗

arXiv2007

Chaoticity of the Wet Granular Gas

In this work we derive an analytic expression for the Kolmogorov-Sinai entropy of dilute wet granular matter, valid for any spatial dimension. The grains are modelled as hard spheres and the influence of the wetting liquid is described according to the Capillary Model, in which dissipation is due to the hysteretic cohesion force of capillary bridges. The Kolmogorov-Sinai entropy is expanded in a series with respect to density. We find a rapid increase of the leading term when liquid is added. This demonstrates the sensitivity of the granular dynamics to humidity, and shows that the liquid significantly increases the chaoticity of the granular gas.

cond-mat.soft↗