Volume Fluctuations and Geometrical Constraints in Granular Packs
Date
2006
Authors
Aste, Tomaso
Journal Title
Journal ISSN
Volume Title
Publisher
American Physical Society
Abstract
I study the structural organization and correlations in very large packings of equally sized spheres, reconstructed in three dimensions with x-ray computed tomography. I show that the geometrical structure can be conveniently studied as a packing of irregular tetrahedra with volume distribution that must decay exponentially with parameters controlled by the conditions of mechanical stability, nonoverlapping, and space filling. I argue that the system’s structure can be described as constituted of two phases: (1) an “unconstrainedâ€phase which freely shares the volume and (2) a “constrained†phase which assumes configurations accordingly with the geometrical constraints. It results that the granular system exploits heterogeneity maximizing freedom and entropy while constraining mechanical stability.
Description
Keywords
Keywords: Computerized tomography; Entropy; Packing; Stability; X ray analysis; Granular system; Mechanical stability; Parameters control; Granular materials
Citation
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Source
Physical Review Letters
Type
Journal article