Shaping high-speed Marangoni flow in liquid films by microscale perturbations in surface temperature
Shaping high-speed Marangoni flow in liquid films by microscale perturbations in surface temperature
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DOI：
10.1063/1.2430777
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发表时间：
2007-01-15
影响因子：
4
通讯作者：
Gianchandani, Yogesh B.
中科院分区：
文献类型：
--
作者：
Basu, Amar S.;Gianchandani, Yogesh B.
作者指出，在80-400微米厚的液膜中，通过在表面上方放置带有集成加热器的扫描显微镜探头(与400微米的间隔)，可以产生各种可控流动模式，包括环状小室和表面二重流。探头在液体表面投射出强烈的温度梯度，从而驱动Marangoni流。在输入功率为20 mW的情况下，在20-200微米的长度尺度上，实验验证了接近3000微米/S的流速。对于液体，如水和油，其表面张力系数约为0.2mN/mK，在表面温度微扰<；1℃的情况下，可以实现FLOWS>；1000µm/S。这种技术使微流控能够在未图案化的衬底上进行。(C)2007年美国物理研究所。
The authors show that a variety of controlled flow patterns, including toroidal cells and surface doublets, can be generated in 80-400 mu m thick liquid films by placing scanning microscopy probes with integrated heaters just above the surface (< 400 mu m separation). The probes project sharp temperature gradients on the liquid surface which drive Marangoni flow. Flow velocities approaching 3000 mu m/s are experimentally demonstrated on length scales of 20-200 mu m with < 20 mW input power. For liquids such as water and oil, in which the surface tension coefficient is approximate to 0.2 mN/m K, flows > 1000 mu m/s can be accomplished with surface temperature perturbations < 1 degrees C. This technique enables microfluidic manipulation on unpatterned substrates. (c) 2007 American Institute of Physics.