Identification of flow regimes and determination of the boundaries for magnetized fluidized bed with Geldart-B particles--颗粒学报PARTICUOLOGY

Wu, F., Song, N., Hu, T., Ho, S. S. H., Cao, J., & Zhang, D. (2023). Surrogate atmospheric dust particles generated from dune soils in laboratory: Comparison with field measurement. Particuology, 72, 29-36. https://doi.org/10.1016/j.partic.2022.02.007

Identification of flow regimes and determination of the boundaries for magnetized fluidized bed with Geldart-B particles

Quanhong Zhu ^{a c *}, Hengjun Gai ^a, Hongbing Song ^a, Meng Xiao ^a, Tingting Huang ^a, Weikang Hao ^b

a College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao 266042, China
b College of Chemical Engineering, Hebei University of Technology, Tianjin 300401, China
c Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China

10.1016/j.partic.2022.01.017

Volume 71, December 2022, Pages 75-89

Received 22 November 2021, Revised 26 January 2022, Accepted 31 January 2022, Available online 16 February 2022, Version of Record 24 February 2022.

E-mail: zhuqh@qust.edu.cn; zhuqh87@163.com

Highlights

• Various flow regimes of magnetized fluidized bed (MFB) were identified.

• Methods for determining borders between two adjacent flow regimes were clarified.

• MFB state also depended on the operation mode with certain operating zones.

• MFB could be polymorphic due to internal friction among unfluidized particles.

• Many of the MFB states were metastable and belonged to amorphous state.

Abstract

The magnetized fluidized bed (MFB) with Geldart-B particles exhibits many distinct flow regimes depending on the magnetic field intensity (H) and gas velocity (U_g). The identification of these regimes was reviewed for the MFB with magnetizable particles and that with binary admixture of magnetizable and nonmagnetizable particles. Meanwhile, methods for determining the boundaries between two adjacent flow regimes were clarified. The MFB state was found to depend not only on H and Ug but also on their application sequence (i.e., operation mode) within certain operating zones. The dependence feature arose from that the MFB therein could have different equilibrium states for the same combination of H and U_g. Furthermore, such a polymorphic characteristic of the MFB was revealed to result from the internal friction among the particles that were in unfluidized/packed state. Many of the MFB states were demonstrated to be in metastable equilibrium. Nevertheless, they differed significantly from the metastates well-known in the discipline of physical chemistry, such as supercooling and superheated. In fact, they belonged to the amorphous/glass state. This review will deepen our hydrodynamic understanding of the MFB and further promote its commercial application in the chemical and biochemical industries.

Graphical abstract

Keywords

Magnetized fluidized bed; Flow regime; Boundary; PolymorphicInternal friction; Amorphous

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