Abstract：Based on the principle of chaotic convection, a passive micromixer with periodic blocks and baffles was designed to enhance the mixing performance of the micro-electro mechanical system. First of all, the static Taguchi analysis was taken to evaluate the relative effectiveness of the geometrical parameters of microchannel structure; then, compared with the available experiments and numerical simulation results, it was verified that the numerical simulation method used in this article was reliable; finally, the fluid flow and mixing characteristics of the micromixer were studied by using commercial software ANSYS CFX. The analysis results indicate that the arrangement of periodic blocks and baffles makes lateral velocity uy periodically change at the center of the micromixer, which leads to the improvement of chaotic convection. When the Reynolds number is over 20, a series of complex expanded vortexes and separated vortexes are generated in the microchannel of micromixer, which leads to the complete mixing of two different fluids.
何秀华, 王岩*, 高凌峰. 内置阻块和挡板微混合器的性能[J]. 排灌机械工程学报, 2018, 36(12): 1282-1287.
HE Xiuhua, WANG Yan*, GAO Lingfeng. Characteristics of micromixer with periodic blocks and baffles. Journal of Drainage and Irrigation Machinery Engin, 2018, 36(12): 1282-1287.
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