DEM simulation of particle percolation in a packed bed--颗粒学报PARTICUOLOGY

Rahman, M., Zhu, H., Yu, A., & Bridgwater, J. (2008). DEM simulation of particle percolation in a packed bed. Particuology, 6(6), 475–482. https://doi.org/10.1016/j.partic.2008.07.016

DEM simulation of particle percolation in a packed bed

Mahbubur Rahman ^a *, Haiping Zhu ^a, Aibing Yu ^a, John Bridgwater ^b

a Lab for Simulation and Modeling of Particulate Systems, School of Materials Science and Engineering, The University of New South Wales, Sydney, NSW 2052, Australia
b Department of Chemical Engineering, University of Cambridge, Cambridge CB2 3RA, UK

10.1016/j.partic.2008.07.016

Volume 6, Issue 6, December 2008, Pages 475-482

Received 10 March 2008, Accepted 15 July 2008, Available online 13 November 2008.

E-mail: mahbub@materials.unsw.edu.au

Highlights

Abstract

The phenomenon of spontaneous particle percolation under gravity is investigated by means of the discrete element method. Percolation behaviors such as percolation velocity, residence time distribution and radial dispersion are examined under various conditions. It is shown that the vertical velocity of a percolating particle moving down through a packing of larger particles decreases with increasing the restitution coefficient between particles and diameter ratio of the percolating to packing particles. With the increase of the restitution coefficient, the residence time and radial dispersion of the percolating particles increase. The packing height affects the residence time and radial dispersion. But, the effect can be eliminated in the analysis of the residence time and radial dispersion when they are normalized by the average residence time and the product of the packing height and packing particle diameter, respectively. In addition, the percolation velocity is shown to be related to the vertical acceleration of the percolating particle when an extra constant vertical force is applied. Increasing the feeding rate of percolating particles decreases the dispersion coefficient.

Graphical abstract

Keywords

Discrete element method; Particle percolation; Residence time; Radial dispersion

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