Modulated exponential films generated by surface acoustic waves and their role in liquid wicking and aerosolization at a pinned drop.
Modulated exponential films generated by surface acoustic waves and their role in liquid wicking and aerosolization at a pinned drop.
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由表面声波产生的调制指数薄膜及其在固定液滴的液体芯吸和雾化中的作用。
DOI：
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发表时间：
2013
期刊：
影响因子：
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通讯作者：
Hsueh
中科院分区：
文献类型：
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作者：
Daniel Taller;D. Go;Hsueh
指数衰减的声压的散射表面声波（SAW）在接触线的液体薄膜钉到滤纸被示出，以维持一个高曲率的圆锥形尖端与微米大小的调制，其尺寸从尖端呈指数增长。膜中的大的负毛细压力（抵消接触线处的大的正声压所必需的）也产生显著的负流体动力学压力和通过纸的稳健的芯吸作用。这种复杂的压力之间的准静态的圆锥形膜和散装下降的渐近分析表明，所需的SAW功率泵送液体从滤纸和雾化，表示在由滴毛细管压力缩放的声压方面，增长指数相对于两倍的声学衰减常数乘以液滴长度，具有普遍的指前系数。全球快速雾化发生在SAW功率的两倍高，超过该芯吸速率饱和。
The exponentially decaying acoustic pressure of scattered surface acoustic waves (SAWs) at the contact line of a liquid film pinned to filter paper is shown to sustain a high curvature conic tip with micron-sized modulations whose dimension grows exponentially from the tip. The large negative capillary pressure in the film, necessary for offsetting the large positive acoustic pressure at the contact line, also creates significant negative hydrodynamic pressure and robust wicking action through the paper. An asymptotic analysis of this intricate pressure matching between the quasistatic conic film and bulk drop shows that the necessary SAW power to pump liquid from the filter paper and aerosolize, expressed in terms of the acoustic pressure scaled by the drop capillary pressure, grows exponentially with respect to twice the acoustic decay constant multiplied by the drop length, with a universal preexponential coefficient. Global rapid aerosolization occurs at a SAW power twice as high, beyond which the wicking rate saturates.