Rapid micromixing based on multilayer laminar flows

The mixing efficiency of a simple, 32-layered micromixer was evaluated. Two liquids are each divided into 16 streams, and converged into 32 laminar flows by merging five times transversely, in turn. Miscible fluids can be mixed rapidly; and, 31 stable interfaces of fluid layers can be produced for immiscible fluids. This process is expected to increase the scope of high-speed chemical reactions and material syntheses. The micromixer used in this study was fabricated using PMMA plates which are easily processed. Mixing efficiency was evaluated by confocal fluorescence microscopy and computational fluid dynamics simulation. The results indicate that about 90% mixing was achieved within 1 s after the streams had been merged at a now rate of 150 mul/min.