Electroviscous Effects in the Electrolyte Liquid Flow Through Heterogeneously Charged Non-uniform Slit Microfluidic Device

In this work, electroviscous effects in fully developed liquid flow through heterogeneously charged non-uniform microfluidic device have been investigated numerically. Charge heterogeneity is considered at the walls of the microchannel, and liquid is assumed as the symmetric (1:1) electrolyte solution. A finite element method (FEM) is used to solve the governing equations such as the Poisson’s, Nernst-Planck, and Navier–Stokes equations to obtain the total potential, ionic concentration, velocity and pressure fields for wide ranges of the governing parameters (3 ≤ \(\text{K}\)  ≤ 9, 4 ≤ \({\text{S}}_{1}\)  ≤ 16, and 0 ≤ \({\text{S}}_{\text{r}}\)  ≤ 2). In the present study, the effects of the governing parameters ( \(\text{K}\) , \({\text{S}}_{1}\) , and \({\text{S}}_{\text{r}}\) ) on the flow fields and induced electric field strength have been analyzed.