Brosseau Quentin, Vlahovska Petia M
School of Engineering, Brown University, Providence, Rhode Island 02912, USA.
Phys Rev Lett. 2017 Jul 21;119(3):034501. doi: 10.1103/PhysRevLett.119.034501. Epub 2017 Jul 20.
Tip streaming generates micron- and submicron-sized droplets when a thin thread pulled from the pointy end of a drop disintegrates. Here, we report streaming from the equator of a drop placed in a uniform electric field. The instability generates concentric fluid rings encircling the drop, which break up to form an array of microdroplets in the equatorial plane. We show that the streaming results from an interfacial instability at the stagnation line of the electrohydrodynamic flow, which creates a sharp edge. The flow draws from the equator a thin sheet which destabilizes and sheds fluid cylinders. This streaming phenomenon provides a new route for generating monodisperse microemulsions.
当从液滴尖端拉出的细线分解时，液滴流会产生微米级和亚微米级的液滴。在此，我们报告了置于均匀电场中的液滴赤道处的液滴流情况。这种不稳定性会产生环绕液滴的同心流体环，这些环会破裂，在赤道平面上形成一系列微滴。我们表明，这种液滴流是由电流体动力学流动的停滞线处的界面不稳定性导致的，该不稳定性会形成一个尖锐边缘。流动从赤道处抽取一层薄片，该薄片会失稳并脱落流体圆柱体。这种液滴流现象为生成单分散微乳液提供了一条新途径。
