Simplified Estimation of Some Main Characteristics of Pores and Constrictions in Granular Materials
Résumé
The void space of granular materials can be considered as a collection of poly-sized pore bodies separated by narrow pore throats or constrictions. Pore network models have been developed to estimate the probable path length covered by fine particles flowing through a granular filter. For this calculation two pieces of information are required: the constriction size distribution and the mean void spacing between two constrictions which corresponds to the mean pore diameter. Different assumptions have been previously made in the literature to determine this void spacing. However, they all neglect the influence of the density and thus, the estimation of this quantity remains an open issue. This paper compares different definitions for the mean pore size based on statistical analyses performed on numerical samples composed of spheres by means of the Discrete Element Method. Different sphere packings with different gradings and density states were considered and a weighted Delaunay tessellation was applied to extract the main void characteristics. In a second part, a simple formula is proposed to quickly estimate the equivalent sieve opening size of the granular filter. This value is very close to the mode value of the constriction size distribution which is related to the most represented constriction size in a granular material.
Domaines
| Origine | Fichiers produits par l'(les) auteur(s) |
|---|---|
| Licence |