十字型微通道内气泡形成的实验观察Formation of Dispersed Small Bubbles in Flow-Focusing Microchannels
付涛涛,惠晓荣,朱春英,马友光,李怀志
摘要(Abstract)：
采用高速摄像仪对聚焦十字型微装置内分散小气泡的生成进行了研究。方形截面微通道的尺寸分别为400μm×400μm和600μm×600μm。氮气为气相,加入表面活性剂十二烷基硫酸钠(sodium dodecyl sulfate,SDS)(0～0.5%(wt))的水—甘油(25%(wt),50%(wt),62%(wt))溶液为液相。考察了不同的操作条件如液体流速、黏度和表面张力对气泡生成尺寸的影响。泡状区内生成的气泡尺寸随连续相流体流量和黏度的增大而减小,随表面张力的增大而增大。讨论了气泡的生成机理,提出了一个新的指数模型来描述气泡生成尺寸与局部毛细管数的关系。
关键词(KeyWords)： 微通道;气泡;高速摄像仪;聚焦十字型微装置;微流体
基金项目(Foundation): 国家自然科学基金资助项目(20876107);; 化学工程国家重点实验室开放课题(SKL-ChE-08B06);; 教育部高校引智项目(B06006)资助
作者(Author): 付涛涛,惠晓荣,朱春英,马友光,李怀志
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