Multiscale synergistic enhancement mechanism of solid—liquid mixing in multi-shaft stirred reactors under variable-speed operation

Meng Tong; Wang Yu; Tian Yijuan; Qin Shuang; Lin Yuyan; Liu Peiqiao; Wang Yundong; Liu Zuohua

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Multiscale synergistic enhancement mechanism of solid—liquid mixing in multi-shaft stirred reactors under variable-speed operation

Updated：2026-05-14

- Multiscale synergistic enhancement mechanism of solid—liquid mixing in multi-shaft stirred reactors under variable-speed operation
- Chinese Journal of Chemical Engineering Vol. 90, Issue 2, Pages: 293-307(2026)
- Affiliations：
  
  School of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400044, China
  Department of Industrial Chemistry “Toso Montanari”, University of Bologna, Bologna 40131, Italy
  State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing 400044, China
  Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
- Author bio：
  
  Corresponding author. E-mail address: liuzuohua@cqu.edu.cn (Z. Liu).
- Funds：
- DOI：
  CLC：
- Received：29 July 2025，
  
  Revised：2025-09-25，
  
  Accepted：25 September 2025，
  
  Online First：11 November 2025，
  
  Published：2026-02
- Accepted：
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Meng Tong, Wang Yu, Tian Yijuan, et al. Multiscale synergistic enhancement mechanism of solid—liquid mixing in multi-shaft stirred reactors under variable-speed operation[J]. Chinese Journal of Chemical Engineering, 2026, 90(2): 293-307.
DOI：

Meng Tong, Wang Yu, Tian Yijuan, et al. Multiscale synergistic enhancement mechanism of solid—liquid mixing in multi-shaft stirred reactors under variable-speed operation[J]. Chinese Journal of Chemical Engineering, 2026, 90(2): 293-307. DOI：

摘要

Abstract

Research on the solid—liquid mixing process and its enhancement mechanisms in multi-shaft stirred reactors still face challenges that limit its industrial applications. This work employs the RNG

—

model combined with the EE-KTGF model to numerically simulate the solid—liquid mixing process within a multi-shaft stirred reactor

yielding satisfactory results when compared to experimental data. Comparative analysis of the solid—liquid mixing performance under four different operational conditions reveals that applying variable speed conditions to the bottom impeller results in a smaller solid concentration gradient

reduced particle settling rates

and an improvement in solid homogeneity by 2.74% to 3.22% compared to other operational conditions. This operational condition enables more effective suspension and uniform distribution of solid particles throughout the reactor

thereby enhancing overall mixing efficiency. Flow field analysis under different operational conditions indicates that applying variable speed to the bottom impeller significantly improves flow field stability

reduces axial back-mixing

and optimizes the axial distribution of solid particles. Further dynamic mode decomposition of the flow field and time series analysis of modal coefficients elucidate a multi-scale synerg

istic nesting chaos-enhanced mechanism characterized by “macroscopic stability

mesoscopic matching

and microscopic resonance”. This work provides a theoretical foundation for the design and operational optimization of multi-shaft stirred reactors.

关键词

Keywords

references

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