Measuring segregation characteristics of industrially relevant granular mixtures: Part I -- A continuum model approach

TL;DR

This paper introduces a method to estimate the segregation parameter in granular mixtures using concentration profiles and validates it with simulations, emphasizing practical applicability and sensitivity to flow conditions.

Contribution

A new continuum model-based method for estimating segregation parameters from concentration profiles validated through DEM simulations.

Findings

Estimated segregation parameter S aligns within 10% of direct measurements.

Accuracy depends on velocity profile, less on diffusion coefficient.

Method suitable for practical experimental application.

Abstract

We present a method to estimate the segregation parameter, $S,$ a key input in a continuum transport model of particulate flows. $S$ is determined by minimizing the difference between measured and model-predicted concentration profiles. To validate the approach, we conduct discrete element method simulations of size-bidisperse mixtures in quasi-2D bounded heap flow; the resulting data show that $S$ calculated from concentration profiles is consistent with the directly measured value. The method's accuracy depends critically on the velocity profile during filling, but only weakly on the diffusion coefficient. When the velocity profile is nominally spanwise invariant, the error between estimated and measured $S$ is $10\%$. This method is intended for practical application (described in Part II), so we restrict characterization of the velocity profile to that which can be readily determined experimentally, and explore the sensitivity of concentration profiles to variation of the gap between the sidewalls of the heap.