Lattice-Boltzmann simulation of fluid flow through packed beds of uniform ellipsoids

Fluid flow through packed beds of uniform ellipsoids is studied by a parallel lattice-Boltzmann (LB) model. The packed beds are generated by means of discrete element method and have a wide range of particle sphericity. First, the LB model is used to validate the drag force coefficient of a single ellipsoid. The validated model is then extended to study the effects of sphericity and porosity on the fluid flow and quantify the drag force on particles in packed beds. Some unique flow structures are identified in relation to tortuous pore structures. Due to non-uniform structure and flow, the fluid-particle interaction forces vary giving a distribution. The results suggest that the mean drag forces on oblate particles are more sensitive to aspect ratio and hence sphericity than prolate ones. Based on the simulated data, a new equation is proposed to calculate the mean drag force on particles. The results show that the new equation is more accurate than the correlations in the literature. (C) 2015 Elsevier B.V. All rights reserved.