Electrohydrodynamic tip streaming and emission of charged drops from liquid cones
Electrohydrodynamic tip streaming and emission of charged drops from liquid cones
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DOI：
10.1038/nphys807
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发表时间：
2008-02-01
期刊：
影响因子：
19.6
通讯作者：
Basaran, Osman A.
中科院分区：
文献类型：
--
作者：
Collins, Robert T.;Jones, Jeremy J.;Basaran, Osman A.
当液体受到足够强的电场时，它可以被诱导从其表面形成的锥形尖端结构中发射出薄的流体射流。从雷雨云中的雨滴到电喷雾质谱中的垂坠雨滴，这种行为既有基础意义又有实际意义。但是，这些微观/纳米尺度的射流与它们形成的宏观液滴和薄膜之间的长度尺度存在巨大差异，这使得对控制这种现象的电流体动力学（EHD）过程进行建模变得困难。在这里，我们报告了模拟和实验，能够全面了解在EHD尖端从有限导电性的液体膜流动过程中锥体形成、射流发射和破裂的机制。模拟结果表明，如果液体完全导电或完全绝缘，EHD尖端流不会发生，这使我们能够建立一个缩放定律来预测射流破裂产生的液滴的大小。
When a liquid is subject to a sufficiently strong electric field, it can be induced to emit thin fluid jets from conical tip structures that form at its surface. Such behaviour has both fundamental and practical implications, from raindrops in thunderclouds to pendant drops in electrospray mass spectrometry. But the large difference in length scales between these microscopic/nanoscopic jets and the macroscopic drops and films from which they emerge has made it difficult to model the electrohydrodynamic (EHD) processes that govern such phenomena. Here, we report simulations and experiments that enable a comprehensive picture of the mechanisms of cone formation, jet emission and break-up that occur during EHD tip streaming from a liquid film of finite conductivity. Simulations show that EHD tip streaming does not occur if the liquid is perfectly conducting or perfectly insulating, and enable us to develop a scaling law to predict the size of the drops produced from jet break-up.