CFD-DEM study of impacts of the porous distributor medium on fluidization characteristics of a 2D-fluidized bed--颗粒学报PARTICUOLOGY

Wang, F., Zeng, Y., & Yan, H. (2024). CFD-DEM study of impacts of the porous distributor medium on fluidization characteristics of a 2D-fluidized bed. Particuology, 87, 54-73. https://doi.org/10.1016/j.partic.2023.07.017

CFD-DEM study of impacts of the porous distributor medium on fluidization characteristics of a 2D-fluidized bed

Fei Wang, Yishan Zeng, Hao Yan ^*

School of Mechanical Engineering, Hefei University of Technology, Hefei, 230009, China

10.1016/j.partic.2023.07.017

Volume 87, April 2024, Pages 54-73

Received 31 March 2023, Revised 19 July 2023, Accepted 31 July 2023, Available online 8 August 2023, Version of Record 21 August 2023.

E-mail: yanying0708@126.com

Highlights

• CFD-DEM coupled with the porous medium model is proposed.

• The accuracy of the CFD-DEM coupled with the porous medium model is verified.

• The flow resistance of the porous medium affects the fluidization behavior.

• The mixing quality is significantly improved due to the high flow resistance.

• The particle trajectories of the dead zone are affected by the flow resistance.

Abstract

Gas–solid bubbling fluidized beds are widely used in chemical, energy, construction, and other industrial fields due to their excellent fluidization performance. 2D-fluidized beds with planar rectangular columns of finite thickness are widely used in fluidized bed studies, and it is essential for understanding the hydrodynamics of gas-particle systems. Moreover, the distributor (porous medium) at the bottom of the bed has a crucial influence on the fluidization performance of the 2D-fluidized bed. In this work, the fluidization mechanism and gas–solid dynamic characteristics of the fluidized bed under three porous media are studied by CFD–DEM coupled with the porous medium model, and the accuracy of numerical simulation is verified by a high-speed photography experiment. Results show that with the increase in the flow resistance of the porous medium, the average and standard deviation of the bubble diameter decrease, and the time and position of particles in the dead zone to participate in the core–annular flow advance. At a low fluidization velocity, the dead zone in the bed can be considerably reduced by increasing the flow resistance.

Graphical abstract

Keywords

Fluidized bed; CFD–DEM; Porous medium; Bubble dynamics; Solid mixing

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