文献类型：期刊文献

英文题名：Experimental and simulation study of flow patterns in the combined flow focusing and T-junction device

作者：Lei, Lei[1,2];Zhang, Hongbo[3];Bergstrom, Donald J.[2];Anthony, Tony[2];Song, Ki-Young[4];Zhang, Wenjun[2]

机构：[1]Changan Univ, Sch Highway, Xian 710064, Peoples R China;[2]Univ Saskatchewan, Dept Mech Engn, Saskatoon, SK S7N 5A9, Canada;[3]East China Univ Sci & Technol, Sch Mech & Power Engn, Complex & Intelligent Syst Ctr, Shanghai 200237, Peoples R China;[4]Beijing Inst Technol, Sch Mechatron Engn, Beijing 100081, Peoples R China

年份：2020

卷号：30

期号：5

外文期刊名：JOURNAL OF MICROMECHANICS AND MICROENGINEERING

收录：;EI(收录号：20202008659807);WOS:【SCI-EXPANDED(收录号:WOS:000521446900001)】；

基金：This research is partially supported by Natural Sciences and Engineering Research Council of Canada (NSERC) through its Discovery Grant program as well as by Saskatchewan Health Research Foundation (SHRF) through its Phase I group grant program to Wenjun (Chris) Zhang.

语种：英文

外文关键词：capillary number of crossflow; microsphere generation; middle flow velocity; combined flow focusing and T-junction (FF-TJ); multiphase flow; sheath flow velocity

摘要：This paper presents a study of droplets generation, particularly examining different regimes or patterns of the flow by a novel device that combines two principles for droplets generation (flow focusing and T-junction (FF-TJ)) under different flow conditions, named combined FF-TJ. The study involves both experiment and simulation. From the experiment mineral oil and distilled water, three regimes (namely continuous regime, jetting regime, and squeezing regime) were found. This finding was subsequently confirmed by the simulation, which thus also gave a validation of the simulation system. The simulation was further employed to study the relationship among various parameters, including the velocities of the flows (i.e. sheath flow, middle flow, and crossflow) in the context the three regimes. We observed that the three regimes were determined by two critical values of the velocity of the middle flow, U-m1 and U-m2. Interestingly, it was further found that the two critical values remained the same, independent of the velocity of the sheath flow. We further investigated the effects of the velocity ratio (the middle flow to the sheath flow, R-m/s) and the capillary number of the crossflow on the microsphere diameter. Overall, this paper presents a comprehensive study of the FF-TJ device and the associated implications for microsphere or droplet generation.