We study the flow properties of granular material draining through an orifice in a two-dimensional glass silo using high-resolution imaging. Two phases are observed: a static solid-like region, and a rapidly flowing fluid-like region. We utilize digital imaging to obtain the interfaces of the static and moving regions as well as the surface profile as the material is emptied. More recently, the velocity profiles have been obtained by direct particle tracking. See preprints page for more information.

Size segregation is observed when multi-sized particles are used with larger particles found in the center of silo in the region of fastest flow. We have quatitatively investigated the development of segregation as a function of time and as a function of size ratio of the particles and the flow rate [1,2].

We have also investigated the effect of interstitial fluid on the development of segregation in granular matter. link.

Relevant Publications

   1. "Size Segregation of Granular Matter in Silo Discharges," A. Samadani, A. Pradhan, and A. Kudrolli Phys. Rev E 60, 7203 (1999).
   2. "Visualization of segregation in granular flows inside silos," A. Samadani, A. Pradhan, and A. Kudrolli, The Proceedings of The ITUAM Symposium on Segregation in Granular Flows, (Kluwer Academic Publishers, 1999).

Arshad Kudrolli
Department of Physics
Clark University
Worcester, MA 01610

Last modified: Nov. 26, 20003

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