Yang C, Li D
Department of Mechanical Engineering, University of Alberta, Edmonton, Alberta, T6G 2G8, Canada
J Colloid Interface Sci. 1997 Oct 1;194(1):95-107. doi: 10.1006/jcis.1997.5091.
The effects of the electrical double layer near the solid-liquid interface and the induced electrokinetic field on the pressure-driven liquid flow through a rectangular microchannel are analyzed in this work. A nonlinear, two-dimensional Poisson-Boltzmann equation governing the electrical double layer field in the cross section of rectangular channels is numerically solved with the use of a finite-difference scheme. A body force caused by the electrical double field and the flow-induced electrokinetic field is considered in the equation of motion. An exact solution to this equation of motion in rectangular microchannels is obtained by employing the Green function formulation. The effects of the ionic concentration of the liquid, the zeta potential of the solid surface, and the size and the shape of microchannels on the fluid velocity distribution, streaming potential, volumetric flow rate, friction coefficient, and apparent viscosity are discussed. The results clearly show that for a liquid solution of low ionic concentration and a solid surface of high zeta potential the liquid flow in rectangular microchannels is significantly influenced by the presence of the electrical double layer field and hence deviates from the flow characteristics described by classical fluid mechanics. Copyright 1997 Academic Press. Copyright 1997Academic Press
本文分析了固液界面附近的双电层以及感应电动场所产生的电场对压力驱动液体通过矩形微通道流动的影响。利用有限差分格式对控制矩形通道横截面上双电层场的非线性二维泊松-玻尔兹曼方程进行了数值求解。在运动方程中考虑了由双电场和流动感应电动场所引起的体力。通过采用格林函数公式，得到了矩形微通道中该运动方程的精确解。讨论了液体的离子浓度、固体表面的zeta电位以及微通道的尺寸和形状对流体速度分布、流动电位、体积流量、摩擦系数和表观粘度的影响。结果清楚地表明，对于低离子浓度的液体溶液和高zeta电位的固体表面，矩形微通道中的液体流动受到双电层场的显著影响，因此偏离了经典流体力学所描述的流动特性。版权所有1997年学术出版社。版权所有1997年学术出版社
