Modelling density segregation in flowing bidisperse granular materials

Hongyi Xiao, Paul B. Umbanhowar, Julio M. Ottino, Richard M. Lueptow*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

57 Scopus citations


Preventing segregation in flowing granular mixtures is an ongoing challenge for industrial processes that involve the handling of bulk solids. A recent continuum-based modelling approach accurately predicts spatial concentration fields in a variety of flow geometries for mixtures varying in particle size. This approach captures the interplay between advection, diffusion and segregation using kinematic information obtained from experiments and/or discrete element method (DEM) simulations combined with an empirically determined relation for the segregation velocity. Here, we extend the model to include density-driven segregation, thereby validating the approach for the two important cases of practical interest. DEM simulations of density bidisperse flows of mono-sized particles in a quasi-two-dimensional-bounded heap were performed to determine the dependence of the density-driven segregation velocity on local shear rate and particle concentration. The model yields theoretical predictions of segregation patterns that quantitatively match the DEM simulations over a range of density ratios and flow rates. Matching experiments reproduce the segregation patterns and quantitative segregation profiles obtained in both the simulations and the model, thereby demonstrating that the modelling approach captures the essential physics of density-driven segregation in granular heap flow.

Original languageEnglish (US)
Article number20150856
JournalProceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences
Issue number2191
StatePublished - Jul 1 2016


  • Chemical engineering
  • Continuum model
  • Density segregation
  • Granular flows

ASJC Scopus subject areas

  • Mathematics(all)
  • Engineering(all)
  • Physics and Astronomy(all)


Dive into the research topics of 'Modelling density segregation in flowing bidisperse granular materials'. Together they form a unique fingerprint.

Cite this