(270g) Time Dependent Size Segregation of Binary Granular Mixtures Flowing over a Chute | AIChE

(270g) Time Dependent Size Segregation of Binary Granular Mixtures Flowing over a Chute

Authors 

Sahu, V. K., Indian Institute of Technology, Kanpur
Patro, S., Indian Institute of Technology, Kanpur
Majumdar, A., Indian Institute of Technology, Kanpur
Tripathi, A., Indian Institute of Technology, Kanpur
Transient size segregation and flow behavior of bi-disperse granular mixtures flowing over an inclined surface under the influence of gravity is studied using DEM simulations and theory. A recently developed particle force-based size segregation theory has been shown to predict the steady-state behavior of binary granular mixtures successfully [1]. This promising theory of binary mixtures is explored in detail in this work by comparing the theoretical predictions with DEM simulations. The inter-coupling of size segregation with rheology [2] is accounted to predict various properties of interest such as specie concentration, inertial number, velocity, pressure and shear stress at different times. A two-way coupled continuum model to solve the momentum balance equations along with particle force-based segregation transport equation and mixture rheology is developed using Matlab PDEPE solver. Figure shows the comparison of theoretically predicted time dependent concentration profiles (solid lines) with DEM simulations (symbols) for a binary mixture having equal composition of each species with size ratio r = 1.25 flowing over a chute of inclination angle of 25o. The time-dependent evolution of flow properties from the continuum model are found to be in good agreement with the DEM simulations for different size ratios for a wide range of compositions.

References:
[1] Anurag Tripathi, Alok Kumar, Mohit Nema, and D. V. Khakhar. “Theory for size segregation in flowing granular mixtures based on computation of forces on a single large particle”. Phys. Rev. E, 103:L031301, 2021.
[2] Anurag Tripathi and D. V. Khakhar. “Density difference-driven segregation in a dense granular flow”. J. Fluid Mech., 717:643–669, 2013.