Particle shape effect on hydrodynamics and heat transfer in spouted bed: A CFD

E, D., Zhou, P., Guo, S., Zeng, J., Cui, J., Jiang, Y., . . . Kuang, S. (2022). Particle shape effect on hydrodynamics and heat transfer in spouted bed: A CFD–DEM study. Particuology, 69, 10-21. https://doi.org/10.1016/j.partic.2021.11.009

Particle shape effect on hydrodynamics and heat transfer in spouted bed: A CFD–DEM study

Dianyu E ^a *, Peng Zhou ^a, Suya Guo ^a, Jia Zeng ^a, Jiaxin Cui ^a *, Youyuan Jiang ^b, Yuanxiang Lu ^c, Zeyi Jiang ^c, Zhengquan Li ^a, Shibo Kuang ^d

a Jiangxi Provincial Key Laboratory for Simulation and Modelling of Particulate Systems, Jiangxi University of Science and Technology, Ganzhou 341000, China
b Ironmaking Plant, Xiangtan Iron and Steel Corporation of Hunan Hualing, Xiangtan 411101, China
c School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China
d ARC Research Hub for Computational Particle Technology, Department of Chemical Engineering, Monash University, Clayton, VIC 3800, Australia

10.1016/j.partic.2021.11.009

Volume 69, October 2022, Pages 10-21

Received 6 October 2021, Revised 5 November 2021, Accepted 24 November 2021, Available online 6 December 2021, Version of Record 21 December 2021.

E-mail: dianyu.e@jxust.edu.cn; jiaxin.cui@jxust.edu.cn

Highlights

• Flow, heat transfer and related microstructures are analyzed by a CFD-DEM model.

• Ellipsoidal particles lead to larger gas bubbles and prolate spheroids form the largest bubble.

• Ellipsoidal spheroids have larger fluid drag force and rotational kinetic energy.

• Oblate spheroids present good heat transfer efficiency while prolate ones show an opposite trend.

Abstract

Spouted bed has drawn much attention due to its good heat and mass transfer efficiency in many chemical units. Investigating the flow patterns and heat and mass transfer inside a spouted bed can help optimize the spouting process. Therefore, in this study, the effects of particle shape on the hydrodynamics and heat transfer in a spouted bed are investigated. This is done by using a validated computational fluid dynamics–discrete element method (CFD–DEM) model, considering volume–equivalent spheres and oblate and prolate spheroids. The results are analysed in detail in terms of the flow pattern, microstructure, and heat transfer characteristics. The numerical results show that the prolate spheroids (Ar = 2.4) form the largest bubble from the beginning of the spouting process and rise the highest because the fluid drag forces can overcome the interlocking and particle–particle frictional forces. Compared with spherical particles, ellipsoidal spheroids have better mobility because of the stronger rotational kinetic energy resulting from the rough surfaces and nonuniform torques. In addition, the oblate spheroid system exhibits better heat transfer performance benefiting from the larger surface area, while prolate spheroids have poor heat transfer efficiency because of their orientation distribution. These findings can serve as a reference for optimizing the design and operation of complex spouted beds.

Graphical abstract

Keywords

Spouted bed; Gas–solid flow; Particle shape; CFD–DEM; Heat transfer

文章导读