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arXiv · 1002.2923

Heterogeneous structure of granular aggregates with capillary interactions

Michael Berhanu·Arshad Kudrolli
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Abstract

We investigate the spatial structure of cohesive granular matter with spheres floating at an air-liquid interface that form disordered close packings with pores in between. The interface is slowly lowered in a conical container to uniformly compress and study the system as a function of area fraction $ϕ$. We find that the free area distributions associated with Voronoi cells show significant exponential tails indicating greater heterogeneity compared with random distributions at low $ϕ$ with a crossover towards a $Γ$-distribution as $ϕ$ is increased. Further, we find significant short range order as measured by the radial correlation function and the orientational order parameter even at low and intermediate $ϕ$, which is absent when particles interact only sterically.

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Michael Berhanu, Arshad Kudrolli. 2010-07-23. Heterogeneous structure of granular aggregates with capillary interactions. https://doi.org/10.1103/physrevlett.105.098002

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