Study on Friction Coefficient of Liquid Flow through a Rectangular MicroChannel with Electrokinetic Effects
The influences of the electrical double Iayer(EDL) field near a solid-liquid interface and induced electrokinetic field on pressure-driven liquid flow through microchannels are analyzed. The equation governing the EDL field in the cross section of rectangular channels is a nonlinear, two-dimensional Poisson-Boltzmann equation. A body force caused by the EDL field and induced electrokinetic field is considered in the equation of motion. The governing equations are numerically solved with the use of a finite control volume scheme. The electrokinetic effects on the flow velocity and the friction coefficient for the microchannel are discussed. The results show that the flow velocity in microchannel predicted by the model with electrokinetic effect is lower than that predicted by the the macroscale fluid theory (without electrokinetic effect). The friction coefficients predicted by the model with electrokinetic effect were found to be higher than that predicted by the macroscale fluid theory. It is different from that the friction coefficient predicted by the macroscale fluid theory for a rectangular channel is dependently only on the aspect ratio (H/W). The friction coefficient of the microscale liquid flow is influenced by the ionic concentration of the liquid, the zeta potential and the size of microchannels. The friction coefficient increases as the ionic concentration of the aqueous solution decreases in the same microchannel. And stronger deviations were observed as the hydraulic diameter decreases with the same aspect ratio.
electokinetic effect friction coefficient finite control volume scheme Poisson-Boltzmann equation microchannel
Zhang Peng Zuo Chuncheng Liu Xutao
School of Mechanical Electronic and Information Engineering, China University of Mining and Technolo College of Mechanical Science and Engineering, Jilin University, Changchun 130025, China
国际会议
2010 International Conference on Digital Manufacturing and Automation(2010 数字制造与自动化国际会议 ICDMA 2010)
长沙
英文
485-489
2010-12-18（万方平台首次上网日期，不代表论文的发表时间）