Geometry-induced Oscillations of Finite Bubbles in Microchannels
Geometry-induced Oscillations of Finite Bubbles in Microchannels
复制标题
微通道中有限气泡的几何诱导振荡
DOI：
10.1016/j.piutam.2014.01.050
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
Jisiou M
中科院分区：
文献类型：
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作者：
Jisiou M
我们发现了当半无限空气指和有限气泡从微通道中置换粘性流体时出现的新的传播模式。在矩形横截面内存在轴向均匀的矩形闭塞导致模式的穆尔性，与未闭塞通道中存在的单一对称模式相反。对于空气指，不对称1，振荡2和本地化模式3首次确定在毫米通道坚持在微米尺度，确认显着的引力效应是不必要的，以支持这些国家。足够大的有限气泡表现出具有数量相似的流动测量的类似模式，这表明支持有限气泡的传播模式的物理机制与针对空气指状件4所识别的物理机制相同。与空气指相反，在空气指中，振荡总是在指尖附近开始并向后传播，有限气泡中的振荡可以从气泡的任一端产生。
We characterise novel propagation modes that occur when semi-infinite air fingers and finite air bubbles displace viscous fluid from microchannels. The presence of an axially-uniform rectangular occlusion within a rectangular cross-section leads to a mul- tiplicity of modes, in contrast to the single symmetric mode present in unoccluded channels. For air fingers, the asymmetric 1, oscillatory 2 and localised modes 3 first identified in millimetric channels persist at the micron-scale, confirming that significant gravitational effects are not necessary to support these states. Sufficiently large finite bubbles exhibit analogous modes with quanti- tatively similar flow measures, indicating that the physical mechanisms supporting the propagation modes of finite bubbles are the same as those identified for the air fingers 4. In contrast to the air fingers, in which oscillations are always initiated near the finger tip and propagate backwards, oscillations in finite bubbles can arise from either end of the bubble.