Transient electroosmotic flow of two-layer Newton fluids through a slit microchannel

• 1、School of Mathematical Science, Inner Mongolia University, Hohhot 010021
• 2、School of Mathematical Science, Inner Mongolia University, Hohhot, Inner Mongolia 010021
• 3、School of Mathematics and Statistics, Inner Mongolia University of Finance and Economics, Hohhot, Inner Mongolia 010071

Abstract：Using Laplace transform method, semi-analytical solutions are presented for transient Electroosmotic flow of two-layer fluids between micro-parallel plates. The solution involves solving the linearized Poisson-Boltzmann equation, together with the unsteady Cauchy momentum equation. The velocity expressions of these two layers were obtained respectively. By numerical computations of inverse Laplace transform, the influence of viscosity ratio μ, density ratio ρ, dielectric constant ratio ε of layer II to layer I, interface charge density jump Q and interface zeta potential△ψdifference on transient velocity amplitude is presented. In addition, the velocity amplitude becomes large with the interface zeta potential difference under steady status. The velocity amplitude becomes small with the increase of the viscosity under steady status. Larger dielectric constant ratio leads to larger velocity under steady status. The density ratio has little effect on the EOF velocity.

Keywords： hydromechanics micro-parallel plates EDL unsteady EOF two-layer Newton fluids