CFD-DEM simulation of spouting of corn-shaped particles--颗粒学报PARTICUOLOGY

Ren, B., Zhong, W., Chen, Y., Chen, X., Jin, B., Yuan, Z., & Lu, Y. (2012). CFD-DEM simulation of spouting of corn-shaped particles. Particuology, 10(5), 562–572. https://doi.org/10.1016/j.partic.2012.03.011

CFD-DEM simulation of spouting of corn-shaped particles

Bing Ren, Wenqi Zhong^*, Yu Chen, Xi Chen, Baosheng Jin, Zhulin Yuan, Yong Lu

Ministry of Education of Key Laboratory of Energy Thermal Conversion and Control, School of Energy and Environment, Southeast University, Nanjing, 210096, China

10.1016/j.partic.2012.03.011

Volume 10, Issue 5, October 2012, Pages 562-572

Received 23 October 2011, Revised 10 January 2012, Accepted 22 March 2012, Available online 25 June 2012.

E-mail: wqzhong@seu.edu.cn

Highlights

► Spouting of corn-shaped particles was simulated using a 3D CFD-DEM model with corn-shaped particles constructed by a multi-sphere method.

► The 4-spherical element construction showed smaller discrepancies between simulated and experimental results.

► Particle concentration increases in the spout region but decreases in the fountain region along the radial direction.

Abstract

Three dimensionally coupled computational fluid dynamics (CFD) and discrete element method (DEM) were used to investigate the flow of corn-shaped particles in a cylindrical spouted bed with a conical base. The particle motion was modeled by the DEM, and the gas motion by the k-ɛ two-equation turbulent model. A two-way coupling numerical iterative scheme was used to incorporate the effects of gas–particle interactions in terms of momentum exchange. The corn-shaped particles were constructed by a multi-sphere method. Drag force, contact force, Saffman lift force, Magnus lift force, and gravitational force acting on each individual particle were considered in establishing the mathematical modeling. Calculations were carried out in a cylindrical spouted bed with an inside diameter of 200 mm, a height of 700 mm, and a conical base of 60°. Comparison of simulations with experiments showed the availability of the multi-sphere method in simulating spouting action with corn-shaped particles, but it depended strongly on the number and the arrangement of the spherical elements. Gas–solid flow patterns, pressure drop, particle velocity and particle concentration at various spouting gas velocity were discussed. The results showed that particle velocity reaches a maximum at the axis and then decreases gradually along the radial direction in the whole bed. Particle concentration increases along the radial direction in the spout region but decreases in the fountain region, while it is nearly constant in the annulus region. Increasing spouting gas velocity leads to larger pressure drop, remarkably increased speed of particle moving upward or downward, but decreased particle concentration.

Graphical abstract

Keywords

Gas–solid flow; Discrete element method; Spouted bed; Corn-shaped particle; Multi-sphere method

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