SCI和EI收录∣中国化工学会会刊

中国化学工程学报 ›› 2022, Vol. 50 ›› Issue (10): 108-116.DOI: 10.1016/j.cjche.2022.07.008

• Fluid Dynamics and Transport Phenomena • 上一篇    下一篇

Effect of swirling addition on the liquid mixing performance in a T-jets mixer

Chunhui Li1, Bin Wu2, Junjie Zhang1, Peicheng Luo1   

  1. 1 School of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189, China;
    2 Hubei Sanjiang Aerospace Jianghe Chemical Technology Co., Ltd, Yichang 444200, China
  • 收稿日期:2022-03-20 修回日期:2022-07-08 出版日期:2022-10-28 发布日期:2023-01-04
  • 通讯作者: Peicheng Luo,E-mail:luopeicheng@seu.edu.cn
  • 基金资助:
    We acknowledge the financial support from the National Natural Science Foundation of China (22078058). We also thank the Big Data Center of Southeast University for providing the facility support on the numerical simulations in this work.

Effect of swirling addition on the liquid mixing performance in a T-jets mixer

Chunhui Li1, Bin Wu2, Junjie Zhang1, Peicheng Luo1   

  1. 1 School of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189, China;
    2 Hubei Sanjiang Aerospace Jianghe Chemical Technology Co., Ltd, Yichang 444200, China
  • Received:2022-03-20 Revised:2022-07-08 Online:2022-10-28 Published:2023-01-04
  • Contact: Peicheng Luo,E-mail:luopeicheng@seu.edu.cn
  • Supported by:
    We acknowledge the financial support from the National Natural Science Foundation of China (22078058). We also thank the Big Data Center of Southeast University for providing the facility support on the numerical simulations in this work.

摘要: Swirling addition to the stream is beneficial for the fluid mixing. This work aims to study the mixing process intensification in a conventional T-jets mixer by the swirling addition. After experimental verification by the planar laser-induced fluorescence technique, large eddy simulation with the dynamic kinetic energy sub-grid stress model is used to predict how the swirling strength (in terms of swirling number, Sw) and swirling directions affect the mixing performance, e.g. the tracer concentration distribution, mixing time, and turbulent characteristics in the T-jets mixers. Predictions show that the swirling strength is the key factor affecting the mixing efficiency of the process. The overall mixing time, τ90, can be significantly reduced by increasing Sw. Vortex analysis shows that more turbulent eddies appear in the collision zone and the turbulent kinetic energy dissipation rate increases obviously with the swirling addition. When Sw is kept constant, the mixing process can be accelerated and intensified by adding swirling to only one stream, to both streams with the opposite swirling directions, or to both streams with the same swirling directions. Amplification of the mixing process by enlarging the mixer size or increasing the flow rates is also optimized. Thus, this work provides a new strategy to improve the mixing performance of the traditional T-jets mixers by the swirling addition.

关键词: Mixing, T-jets mixer, Swirling, Computational fluid dynamics (CFD), Large eddy simulation

Abstract: Swirling addition to the stream is beneficial for the fluid mixing. This work aims to study the mixing process intensification in a conventional T-jets mixer by the swirling addition. After experimental verification by the planar laser-induced fluorescence technique, large eddy simulation with the dynamic kinetic energy sub-grid stress model is used to predict how the swirling strength (in terms of swirling number, Sw) and swirling directions affect the mixing performance, e.g. the tracer concentration distribution, mixing time, and turbulent characteristics in the T-jets mixers. Predictions show that the swirling strength is the key factor affecting the mixing efficiency of the process. The overall mixing time, τ90, can be significantly reduced by increasing Sw. Vortex analysis shows that more turbulent eddies appear in the collision zone and the turbulent kinetic energy dissipation rate increases obviously with the swirling addition. When Sw is kept constant, the mixing process can be accelerated and intensified by adding swirling to only one stream, to both streams with the opposite swirling directions, or to both streams with the same swirling directions. Amplification of the mixing process by enlarging the mixer size or increasing the flow rates is also optimized. Thus, this work provides a new strategy to improve the mixing performance of the traditional T-jets mixers by the swirling addition.

Key words: Mixing, T-jets mixer, Swirling, Computational fluid dynamics (CFD), Large eddy simulation