Abstract
Free surface flows of granular materials in bounded axisymmetric geometries such as a cylindrical silo are poorly understood. In particular, a detailed description of the local three-dimensional velocity field and predictive models for segregation are lacking. Here, the details of the kinematics of flow in a rising conical heap formed by a centrally fed mixture of spherical particles are investigated using Discrete Element Method (DEM) simulations in a wedge-shaped geometry with periodic azimuthal boundaries. The dependence of the streamwise and surface normal velocity components on the inlet flow rate and silo radius for size-bidisperse and monodisperse mixtures of glass spheres is characterized. Compared to a wedge with frictional sidewalls, the flowing layer is much thicker on average in the axisymmetric case. Using the scalings for kinematics obtained from the DEM simulations, a modified continuum advection-diffusion-segregation model accurately predicts steady-state segregation for axisymmetric conical heap flows of size-bidisperse mixtures.
| Original language | English (US) |
|---|---|
| Article number | 115505 |
| Journal | Chemical Engineering Science |
| Volume | 217 |
| DOIs | |
| State | Published - May 18 2020 |
Funding
The authors thank Yi Fan and Karl Jacob of The Dow Chemical Company for many helpful discussions. This research was funded by The Dow Chemical Company.
Keywords
- Conical heap
- Discrete element method
- Granular materials
- Kinematics
- Segregation
ASJC Scopus subject areas
- General Chemistry
- General Chemical Engineering
- Industrial and Manufacturing Engineering