2017 Impact factor 1.802
Soft Matter and Biological Physics
Eur. Phys. J. E 1, 265-273

Analysis of radial segregation of granular mixtures in a rotating drum

Saikat Chakraborty1 - Prabhu R. Nott1 - J. Ravi Prakash2

1 Department of Chemical Engineering, Indian Institute of Science, Bangalore 560$\,$012, India
2 Department of Chemical Engineering, Indian Institute of Technology Madras, Chennai 400$\,$036, India
prnott@chemeng.iisc.ernet.in

Received 4 June 1999 and Received in final form 28 September 1999

Abstract
This paper considers the segregation of a granular mixture in a rotating drum. Extending a recent kinematic model for grain transport on sandpile surfaces to the case of rotating drums, an analysis is presented for radial segregation in the rolling regime, where a thin layer is avalanching down while the rest of the material follows rigid body rotation. We argue that segregation is driven not just by differences in the angle of repose of the species, as has been assumed in earlier investigations, but also by differences in the size and surface properties of the grains. The cases of grains differing only in size (slightly or widely) and only in surface properties are considered, and the predictions are in qualitative agreement with observations. The model yields results inconsistent with the assumptions for more general cases, and we speculate on how this may be corrected.

PACS
47.55.Kf Multiphase and particle-laden flows - 83.70.Fn Granular solids

Copyright EDP Sciences, Società Italiana di Fisica, Springer-Verlag