Formation of droplets and bubbles in a microfluidic T-junction - scaling and mechanism of break-up
Formation of droplets and bubbles in a microfluidic T-junction - scaling and mechanism of break-up
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DOI：
10.1039/b510841a
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发表时间：
2006-03-01
期刊：
影响因子：
6.1
通讯作者：
Whitesides, GM
中科院分区：
文献类型：
--
作者：
Garstecki, P;Fuerstman, MJ;Whitesides, GM
本文描述了微流控t型结几何形状中液滴和气泡的形成过程。在低毛细数时，破裂不受剪切应力的支配：实验结果支持这样的断言，即破裂动力学的主要贡献来自新兴液滴或气泡的压降。当液滴几乎填满整个通道的横截面时，将液滴与微通道壁分开的薄膜中连续（载体）流体的高阻力导致了这种压降。一个简单的缩放关系，基于这一断言，预测了在两个不混相的流动速率、连续相的粘度、界面张力和装置的几何尺寸范围内，t结中产生的液滴和气泡的大小。
This article describes the process of formation of droplets and bubbles in microfluidic T-junction geometries. At low capillary numbers break-up is not dominated by shear stresses: experimental results support the assertion that the dominant contribution to the dynamics of break-up arises from the pressure drop across the emerging droplet or bubble. This pressure drop results from the high resistance to flow of the continuous ( carrier) fluid in the thin films that separate the droplet from the walls of the microchannel when the droplet fills almost the entire cross-section of the channel. A simple scaling relation, based on this assertion, predicts the size of droplets and bubbles produced in the T-junctions over a range of rates of flow of the two immiscible phases, the viscosity of the continuous phase, the interfacial tension, and the geometrical dimensions of the device.