Alternating current (AC) electroosmotic flow of generalized Maxwell fluids through a circular microtube

Abstract

An analytical solution for the time periodic electroosmotic flow (EOF) of the generalized Maxwell model through a circular microtube is presented by solving the linearized Poisson-Boltzmann equation, together with Cauchy momentum equation and General Maxwell constitutive equation. By numerical calculations, we find that for lower Ω and smaller De, classical plug-like profile of Newtonian fluids is reduced. At lower frequency, the flow field can extend to the whole microtube. At higher frequency, however, the velocity amplitude variations away from electric double layer (EDL) almost decrease to zero. In addition, larger De leads to rapid variations of EOF velocity profiles with increased amplitude. The velocity amplitude of microtube is larger than that of plate microchannel by comparison. Key words: Circular microtube, alternating current (AC) electroosmotic flow, generalized Maxwell fluid, normalized oscillation frequency, relaxation time.