Multi-fluid Eulerian simulation of mixing of binary particles in a gas–solid fluidized bed with a cohesive particle‒particle drag model--颗粒学报PARTICUOLOGY

Wei, L., Jiang, G., Teng, H., Hu, J., & Zhu, J. (2020). Multi-fluid Eulerian simulation of mixing of binary particles in a gas–solid fluidized bed with a cohesive particle‒particle drag model. Particuology, 49, 95-104. https://doi.org/10.1016/j.partic.2018.11.005

Multi-fluid Eulerian simulation of mixing of binary particles in a gas–solid fluidized bed with a cohesive particle‒particle drag model

Liping Wei ^*, Guodong Jiang, Haipeng Teng, Jun Hu, Jianbo Zhu

School of Chemical Engineering, Northwest University, Chemical Engineering Research Center of the Ministry of Education for Advanced Use Technology of Shanbei Energy, and Shaanxi Research Center of Engineering Technology for Clean Coal Conversion, Xi’an 710069, Shaanxi, China

10.1016/j.partic.2018.11.005

Volume 49, April 2020, Pages 95-104

Received 15 January 2018, Revised 23 October 2018, Accepted 16 November 2018, Available online 8 June 2019, Version of Record 26 February 2020.

E-mail: weiliping@nwu.edu.cn

Highlights

• A particle‒particle drag model is extended to cohesive particles flow.

• Mixing of binary particles (Geldart-A and C particles) was simulated.

• Three scales of mixing processes were observed.

Abstract

A particle‒particle (p‒p) drag model is extended to cohesive particle flow by introducing solid surface energy to characterize cohesive collision energy loss. The effects of the proportion of cohesive particles on the mixing of binary particles were numerically investigated with the use of a Eulerian multiphase flow model incorporating the p‒p drag model. The bed expansion, mixing, and segregation of Geldart-A and C particles were simulated with varying superficial velocities and Geldart-C particle proportions, from which we found that the p‒p drag model can reasonably predict bed expansion of binary particles. Two segregation types of jetsam-mixture-flotsam and mixture-flotsam processes were observed during the fluidization processes for the Geldart-A and C binary particle system. The mixing processes of the binary particle system can be divided into three scales: macro-scale mixing, meso-scale mixing, and micro-scale mixing. At a constant superficial velocity the optimal mixing was observed for a certain cohesive particle proportion.

Graphical abstract

Keywords

Fluidization; Cohesive particle; Particle‒particle drag model; Mixing index; Binary particles

文章导读