Numerical and experimental investigations of spiral and serpentine micromixers over a wide Reynolds number range

• Published in: International journal of heat and mass transfer 2023-09, Vol.212, p.124273, Article 124273
• Main Authors: Zhou, Dongjian, Qin, Litao, Yue, Jincai, Yang, Anming, Jiang, Zhen, Zheng, Shiqing
• Format: Article
• Language: English
• Subjects: Confocal microscopy; Dean vortex; Mixing efficiency; Running cost; Serpentine micromixer; Spiral micromixer
• ISSN: 0017-9310; 1879-2189
• DOI: 10.1016/j.ijheatmasstransfer.2023.124273

•Spiral and serpentine micromixers' experimental mixing characteristics agree with simulations over a wide range of Re.•The two-vortex and four-vortex structures of the Dean vortex are observed by the experiments and simulations.•The counter-rotating structure of serpentine micromixer causes poor mixing at low Re.•The running cost is proposed to evaluate the comprehensive performance of the spiral and serpentine micromixers. Micromixers are important components in microfluidic systems and play a pivotal role in chemical processes. In this work, numerical simulation and experimental studies were used to investigate the mixing efficiencies of spiral (S-M) and serpentine (C-S-M) micromixers in a wide Reynolds number (Re) range. We found that the structure of the Dean vortex played a crucial role in the mass transfer of the mixing process. The two structures produced Dean vortices with double vortex structures at the Re of 1 and 300, the mixing efficiency of C-S-M was lower than S-M. A Dean vortex with a four-vortex structure was produced in the two micromixers at the Re of 300 and 500, and the mixing efficiency of C-S-M was higher than S-M. Finally, the running cost (RC) concept was proposed to evaluate the comprehensive efficiencies of the two micromixers, which showed that the RC of S-M was lower at the Re of 50 and 100, and the RC of C-S-M was lower at the Re of 300 and 500. Our research may provide theoretical guidance for the design and application of micromixers.