A pneumatic droplet-on-demand generator
A pneumatic droplet-on-demand generator
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DOI：
10.1007/s00348-003-0629-6
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发表时间：
2003-06-01
影响因子：
2.4
通讯作者：
Chandra, S
中科院分区：
文献类型：
--
作者：
Cheng, S;Chandra, S
描述了一种气动液滴发生器的设计，可按需产生小水滴（直径约 0.2 毫米）。它由一个圆柱形的充满液体的室组成，其底面设有一个小喷嘴，通过电磁阀连接到气瓶。快速打开和关闭阀门会向液体发送压力脉冲，通过喷嘴喷射出单个液滴。室内的气体通过排气孔逸出，因此压力迅速下降并且不会出现更多的液滴。我们拍摄了从喷嘴中喷出的液滴，并记录了室内的压力波动。我们确定了产生单滴所需的压力脉冲的持续时间；较长的脉冲产生卫星滴。可以使用线性稳定性分析的结果来预测尖端分离时水射流的长度和形成的液滴的直径。可以通过提高供应压力、增加压力脉冲的宽度或通过减小泄压孔的尺寸来增加腔中的峰值压力。
The design of a pneumatic droplet generator to produce small (similar to0.2 mm diameter) water droplets on demand is described. It consists of a cylindrical, liquid-filled chamber with a small nozzle set into its bottom surface, connected to a gas cylinder through a solenoid valve. Rapidly opening and closing the valve sends a pressure pulse to the liquid, ejecting a single droplet through the nozzle. Gas in the chamber escapes through a vent hole so that the pressure drops rapidly and more droplets do not emerge. We photographed droplets as they emerged from the nozzle, and recorded pressure fluctuations in the chamber. We determined the duration of the pressure pulse required to generate a single drop; longer pulses produced satellite drops. The length of the water jet when its tip detached and the diameter of the droplet that formed could be predicted using results from linear stability analysis. The peak pressure in the cavity could be increased by raising the supply pressure, increasing the width of the pressure pulse, or by reducing the size of the pressure relief vent.