摘要
微结构引发微通道内不同流体相界面拉伸、折叠及诱导形成二次涡流,对被动式流体混合有着重要的影响。在前期针对单侧带有微结构的微通道内被动式流体混合研究的基础上,本文在微通道两侧设计了不同形式的微结构,并进一步研究微结构排列形式对被动式流体混合的影响。研究结果表明,相较于微结构分布在单侧的微通道,当微结构分布在微通道的两侧时,无法形成多流体层结构,导致流体混合效率降低。同时,由于微结构数量增多,双侧带有微结构的微通道内流动阻力损失增加,达到的最大流量减小。本文研究有助于高效被动式流体混合器设计,促进微流体混合技术在生物医学、化学分析与反应等领域中的应用。
Microstructure could induce the stretching and the folding of the interface between different fluids as well as the secondary flow,which highly influences the fluid mixing in microchannel.Based on the prior study on the fluid mixing in microchannel with microstructures on one side,microchannels with microstructures on two sides were fabricated,and experiments were conducted on the fluid mixing.The experimental results show that,in comparison to the microchannel with microstructures on one side,no multilamellar fluid structure was generated in the microchannel with microstructures on two sides,resulting in a low mixing efficiency.In addition,more structures were designed in the microchannel with microstructures on two sides,which induces high flow resistance and low throughput.This study is of great help for the design of the efficient mixer and the application of the microfluidic technology in variety of fields including biomedicine,analytical chemistry and reaction.
引文
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