Effect of liquid slip in electrokinetic parallel-plate microchannel flow.
Effect of liquid slip in electrokinetic parallel-plate microchannel flow.
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DOI：
10.1016/s0021-9797(02)00158-3
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发表时间：
2003-04
影响因子：
9.9
通讯作者：
Jun Yang;D. Kwok
中科院分区：
文献类型：
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作者：
Jun Yang;D. Kwok
在微通道中，液体在疏水表面的滑移是经常被观察到的。本文将动电输运现象与Navier滑移条件相结合，给出了平行板微通道内振荡流动的解析解。我们的参数结果表明，电动力学传输现象和液体滑移在通道壁都是重要的，应该同时考虑。它们的意义取决于通道壁材料，电解质浓度，和pH值。对于压力驱动流，液体滑移抵消了双电层的影响，并诱导更大的流速。如果忽略滑移，则可以预测较高的表观粘度。对于电渗流，对于厚的双电层，液体滑移改变流速约20%。我们的研究结果为精确控制疏水微流体微机电系统器件中随时间变化的微流提供了设计指导。
Liquid slip at hydrophobic surfaces in microchannels has frequently been observed. We present here an analytical solution for oscillating flow in parallel-plate microchannels by combining the electrokinetic transport phenomena with Navier's slip condition. Our parametric results suggest that electrokinetic transport phenomena and liquid slip at channel walls are both important and should be considered simultaneously. Their significance depends on channel wall material, electrolyte concentration, and pH. For pressure-driven-flow, liquid slip counteracts the effect by the electrical double layer and induces a larger flow rate. A higher apparent viscosity would be predicted if slip is neglected. For electroosmotic flow, liquid slip alters the flow rate by about 20% for a thick electrical double layer. Our results provide design guidelines to precisely control time-dependent microflow in hydrophobic microfluidic microelectromechanical system devices.