Analytic Solutions and Model Assessment for Electrokinetic Flow in Hydrophobic Microchannels with Various Boundary Conditions of Interfacial Electric and Slippage Phenomena

作者：Wang J C; Soong C Y^*; Hwang P W

来源：Journal of the Chinese Society of Mechanical Engineers, 2010, 31(3): 209-220.

• fluid slippage
• microchannel flow
• apparent zeta potential
• hydrophobic wall
• interfacial phenomena

The present study is concerned with a theoretical analysis of pressure-driven electrokinetic flows in hydrophobic microchannels with emphasis on the slip effects under coupling of interfacial electric and fluid slippage phenomena. Nonlinear equations coupling hydrodynamics and electrical field are formulated and the corresponding linear version can be obtained by invoking Debye-Huckel approximation. To facilitate analytic solutions, the electrokinetic parameter K (defined as the ratio of channel semi-height to Debye length) is assumed high enough with electric double layer non-overlapping. Three zeta potential boundary conditions (BCs) including commonly used material true zeta potential and two kinds of slip-dependent relations are considered. Through comparisons of the six analytic solutions (linear and nonlinear models each with 3 BCs), the present analysis provides an assessment of various models with slip effects on electrokinetic flow in hydrophobic microchannels.

• 出版日期2010-6