Lattice-Boltzmann simulation of fluid flow through packed beds of spheres: Effect of particle size distribution

• Published in: Chemical engineering science 2014-09, Vol.116, p.508-523
• Main Authors: Rong, L.W., Dong, K.J., Yu, A.B.
• Format: Article
• Language: English
• Subjects: Computation; Computational fluid dynamics; Computer simulation; Drag; Drag force; Fluid flow; Fluid mechanics; Fluids; Lattice-Boltzmann simulation; Mathematical analysis; Mathematical models; Packed bed; Packed beds; Porous media
• ISSN: 0009-2509; 1873-4405
• DOI: 10.1016/j.ces.2014.05.025

Fluid flowing through packed beds of multi-sized spheres is studied by a parallel lattice-Boltzmann (LB) model. The packed beds are generated by means of the discrete element method. First, the LB model is used to study the effects of size ratio and volume fraction on the fluid flow and quantify the drag forces on binary mixtures of particles. Typical flow behaviours are identified in relation to pore geometries. The results suggest that the polydispersity in particle size enhances local structure heterogeneity and flow non-uniformity, resulting in distributed fluid–particle interaction forces. Then, based on the simulated data, a new equation is formulated to calculate the mean individual drag force. The equation is extended to multicomponent mixtures of particles. The results show that the new equation is more accurate and reliable than those in the literature, and can be generally used in the modelling of particle–fluid flows. •A parallelized LB model is used to quantify the drag forces in packed beds of multi-sized particles.•The velocity distributions in different packed beds are studied.•Drag forces on individual particles show a probability distribution.•Applicability of the literature equations to calculate the mean drag forces is examined.•A new equation is proposed to estimate the mean drag force on particles of different sizes.