Numerical and Experimental Investigations of Spiral and Serpentine Micromixers Over a Wide Reynolds Number Range

Micromixers are important components in microfluidic systems and play a pivotal role in chemical pro-cesses. 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 pro-duced 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 30 0 and 50 0. Our research may provide theoretical guidance for the design and application of micromixers.(c) 2023 Elsevier Ltd. All rights reserved.