CFD–DEM simulation of the pneumatic conveying of fine particles through a horizontal slit--颗粒学报PARTICUOLOGY

Zhou, F., Hu, S., Liu, Y., Liu, C., & Xia, T. (2014). CFD–DEM simulation of the pneumatic conveying of fine particles through a horizontal slit. Particuology, 16, 196–205. https://doi.org/10.1016/j.partic.2014.03.015

CFD–DEM simulation of the pneumatic conveying of fine particles through a horizontal slit

Fubao Zhou ^{a b *}, Shengyong Hu ^b, Yingke Liu ^b, Chun Liu ^b, Tongqiang Xia ^c

a Key Laboratory of Gas and Fire Control for Coal Mines, China University of Mining and Technology, Xuzhou 221008, China
b Faculty of Safety Engineering, China University of Mining and Technology, Xuzhou 221116, China
c State Key Laboratory for Geomechanics and Deep Underground Engineering, China University of Mining and Technology, Xuzhou 221116, China

10.1016/j.partic.2014.03.015

Volume 16, October 2014, Pages 196-205

Received 9 October 2013, Revised 1 March 2014, Accepted 4 March 2014, Available online 27 June 2014.

E-mail: zfbcumt@gmail.com; fubaozhou@yahoo.com.cn

Highlights

• Pneumatic conveying of fine particles in a small scale horizontal slit was studied.

• Stratified, dune, pulsation and periodic plug flows were simulated with varying gas velocity.

• Horizontal gas velocity profile deviated from that of single phase turbulent flow.

• Vertical gas velocity fluctuated up and down.

• An overall voidage decrease or fluctuation was simulated.

Abstract

Fine particles play a significant role in many industrial processes. To study the dynamic behavior of fine particle and their deposition in rock fractures, the pneumatic conveying of fine particles (approximately 100 μm in diameter) through a small-scale horizontal slit (0.41 m × 0.025 m) was studied, which is useful for the sealing technology of underground gas drainage in coal mining production. The CFD–DEM method was adopted to model the gas-particle two-phase flow; the gas phase was treated as a continuum and modeled using computational fluid dynamics (CFD), particle motion and collisions were simulated using the DEM code. Then, the bulk movement of fine particles through a small-scale horizontal slit was explored numerically, and the flow patterns were further investigated by visual inspection. The simulation results indicated that stratified flow or dune flow can be observed at low gas velocities. For intermediate gas velocities, the flow patterns showed pulsation phenomena, and dune flow reappeared in the tail section. Moreover, periodic flow regimes with alternating thick and sparse stream structures were observed at a high gas velocity. The simulation results of the bulk movement of fine particles were in good agreement with the experimental findings, which were obtained by video-imaging experiments. Furthermore, the calculated pressure drop versus gas velocity profile was investigated and compared with relative experimental findings, and the results showed good agreement. Furthermore, the particle velocity vectors and voidage distribution were numerically simulated. Selected stimulation results are presented and provide a reference for the further study of fine particles.

Graphical abstract

Keywords

Gas–solid flow; CFD–DEM; Particle motion; Pneumatic conveying

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