Asymmetric mixing in unbaffled stirred tank reactors: A mini-review

doi:10.1016/j.cjche.2025.04.020

Chinese Journal of Chemical Engineering ›› 2025, Vol. 87 ›› Issue (11): 273-287.DOI: 10.1016/j.cjche.2025.04.020

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Asymmetric mixing in unbaffled stirred tank reactors: A mini-review

Anqi Li¹, Yuan Yao², Xin Zhang¹, Yundong Wang³, Changyuan Tao¹, Zuohua Liu¹

1. School of Chemistry and Chemical Engineering, Chongqing University, Chongqing 401331, China;
2. School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing 401331, China;
3. Department of Chemical Engineering, Tsinghua University, Beijing 100084, China

Received:2025-02-18 Revised:2025-04-22 Accepted:2025-04-24 Online:2025-07-01 Published:2025-11-28
Contact: Yuan Yao,E-mail:yaoy@cqust.edu.cn;Zuohua Liu,E-mail:liuzuohua@cqu.edu.cn
Supported by:
We acknowledge the National Key Research and Development Program of China (2022YFB3504300), the Graduate Research and Innovation Foundation of Chongqing (CYB240045), the Fundamental Research Funds for the Central Universities (2024CDJXY010), and the Large-scale Instrument and Equipment Function Development Program of Chongqing University (gnkf2024019) for supporting this work.

Asymmetric mixing in unbaffled stirred tank reactors: A mini-review

Anqi Li¹, Yuan Yao², Xin Zhang¹, Yundong Wang³, Changyuan Tao¹, Zuohua Liu¹

1. School of Chemistry and Chemical Engineering, Chongqing University, Chongqing 401331, China;
2. School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing 401331, China;
3. Department of Chemical Engineering, Tsinghua University, Beijing 100084, China

通讯作者: Yuan Yao,E-mail:yaoy@cqust.edu.cn;Zuohua Liu,E-mail:liuzuohua@cqu.edu.cn
基金资助:
We acknowledge the National Key Research and Development Program of China (2022YFB3504300), the Graduate Research and Innovation Foundation of Chongqing (CYB240045), the Fundamental Research Funds for the Central Universities (2024CDJXY010), and the Large-scale Instrument and Equipment Function Development Program of Chongqing University (gnkf2024019) for supporting this work.

Abstract

Abstract: The formation, evolution and modelling of organized flow structures (e.g., segregated regions and centre-surface vortices) and their destruction in unbaffled stirred tank reactors (UBSTRs) have been a hot research topic in the field of fluid mixing. In this paper, the relevant researches in the past 30 years were reviewed, focusing on the application of asymmetric mixing. In particular, by drawing on chaotic phenomena in nature and human society (e.g., kneading-dough, traffic flow, frightened school of fish), we propose a fluid mixing mechanism: squeezing-induced chaotic mixing, and further propose a bionics-imitation-simulation design concept for UBSTRs. This concept is also an important inspiration for the design of other chemical reactors.

Key words: Unbaffled stirred tank reactor, Organized flow structure, Asymmetric mixing, Squeezing-induced chaotic mixing, Process-intensification

摘要： The formation, evolution and modelling of organized flow structures (e.g., segregated regions and centre-surface vortices) and their destruction in unbaffled stirred tank reactors (UBSTRs) have been a hot research topic in the field of fluid mixing. In this paper, the relevant researches in the past 30 years were reviewed, focusing on the application of asymmetric mixing. In particular, by drawing on chaotic phenomena in nature and human society (e.g., kneading-dough, traffic flow, frightened school of fish), we propose a fluid mixing mechanism: squeezing-induced chaotic mixing, and further propose a bionics-imitation-simulation design concept for UBSTRs. This concept is also an important inspiration for the design of other chemical reactors.

关键词: Unbaffled stirred tank reactor, Organized flow structure, Asymmetric mixing, Squeezing-induced chaotic mixing, Process-intensification

Anqi Li, Yuan Yao, Xin Zhang, Yundong Wang, Changyuan Tao, Zuohua Liu. Asymmetric mixing in unbaffled stirred tank reactors: A mini-review[J]. Chinese Journal of Chemical Engineering, 2025, 87(11): 273-287.

Anqi Li, Yuan Yao, Xin Zhang, Yundong Wang, Changyuan Tao, Zuohua Liu. Asymmetric mixing in unbaffled stirred tank reactors: A mini-review[J]. 中国化学工程学报, 2025, 87(11): 273-287.

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Asymmetric mixing in unbaffled stirred tank reactors: A mini-review

Asymmetric mixing in unbaffled stirred tank reactors: A mini-review

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