Modelling segregation of bidisperse granular mixtures varying simultaneously in size and density for free surface flows

  title={Modelling segregation of bidisperse granular mixtures varying simultaneously in size and density for free surface flows},
  author={Yifei Duan and Paul B. Umbanhowar and Julio M. Ottino and Richard M. Lueptow},
  journal={Journal of Fluid Mechanics},
Abstract Flowing granular materials segregate due to differences in particle size (driven by percolation) and density (driven by buoyancy). Modelling the segregation of mixtures of large/heavy particles and small/light particles is challenging due to the opposing effects of the two segregation mechanisms. Using discrete element method (DEM) simulations of combined size and density segregation we show that the segregation velocity is well described by a model that depends linearly on the local… 
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