Shear induced particle migration in binary colloidal suspensions
Shear induced particle migration in binary colloidal suspensions
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二元胶体悬浮液中剪切诱导的颗粒迁移
DOI：
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发表时间：
2006
期刊：
影响因子：
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通讯作者：
J. Morris
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文献类型：
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作者：
D. Semwogerere;E. Weeks;J. Morris
本文对压力驱动的布朗颗粒悬浮流中颗粒迁移的时空演化进行了实验研究。直径分别为1.4和3.0m的二元悬浮液通过一根50,500m2的矩形截面毛细管泵送。由此产生的抛物线速度分布引起的剪切速率梯度将颗粒从壁面驱离到通道的中心，在那里剪切速率最低。使用高速激光扫描共聚焦显微镜直接对流动进行成像。观察到了颗粒的尺寸偏析。根据条件的不同，大颗粒或小颗粒都会使中心变富。我们通过跟踪颗粒的横流浓度的演变来测量尺寸偏析的发展。©2008美国物理研究所。编号：10.1063/1.2907378
We present experimental investigations of the spatial and temporal evolution of particle migration in pressure driven flows of Brownian particle suspensions. Binary suspensions of 1.4 and 3.0 m diameter colloidal particles are pumped through a 50 500 m2 rectangular-cross-section capillary tube. Shear rate gradients caused by the resulting parabolic velocity profile drive the particles away from the walls toward the center of the channel, where the shear rate is lowest. The flows are directly imaged using high-speed laser scanning confocal microscopy. Size segregation of the particles is observed. Depending on the conditions, either the large or the small particles enrich the center. We measure the development of the size segregation by tracking the evolution of the cross-stream concentrations of the particles. © 2008 American Institute of Physics. DOI: 10.1063/1.2907378