Similar Region in Electroosmotic Flow Rate for Newtonian and Non-Newtonian Fluids Using Dissipative Particle Dynamics (DPD)

Abstract

In this paper, analysis of electroosmotic flow in Newtonian and non Newtonian fluids in nanochannel with dissipative particle dynamics (DPD) method is presented and our results are validated with analytical solutions. Our aim is that which region or regions, based on the volumetric flow rates, in non-Newtonian fluids are similar with comparison to Newtonian ones in regards to various effective EOF parameters. For numerical simulation, the linearized Poisson Boltzmann for external force calculation is used and DPD method is applied for power law fluids to predict non-Newtonian fluids behavior in electroosmotic in various conditions such as different zeta potential, external electric fields, kh parameter (mainly Debye length and channel height), and flow behavior index. Based on the our results, for certain values of effective parameters, there are regions for volumetric flow rates which both Newtonian and non Newtonian electroosmotic flows have similar behavior while out of these regions, there are obviously significant differences and it is not possible to take Newtonian assumption for these regions. Based on our results validated with analytical solution, simplified assumption of taking non Newtonian fluid as Newtonians ones, in different EOF conditions in most cases, have a clearly inaccuracy and presented method can predict which EOF rates in both cases are correctly similar.