Investigation of Nonlinear Electrokinetic and Rheological Behaviors of Typical Non-Newtonian Biofluids through Annular Microchannels

Abstract

Electroosmosis is the predominant mechanism for flow generation in lab-on-chip devices. Since most biofluids encountered in these devices reveal non-Newtonian behavior, a special understanding of the fundamental physics of the relevant transport phenomena seems vital for an accurate design of such miniaturized devices. In this study, a numerical analysis is presented to explore transport characteristics of typical non-Newtonian biofluids through annular microchannels under combined action of pressure and electrokinetic forces. The flow is considered steady and hydrodynamically fully developed. A finite difference method is used to solve the Poisson-Boltzmann and Cauchy momentum equations, while the classical boundary condition of no velocity-slip for the flow field is applied. The Poisson-Boltzmann equation is solved in the exact form without using the Debye-Hückel approximation. After numerically solving the governing equations, role of the key parameters in hydrodynamic behavior of the flow is analyzed and discussed. Keywords

Effect of Reverting Channels on Heat Transfer Performance of Microchannels with Different Geometries

“…Niazmand et al (2010) studied the rarefaction effects in fully developed flow in rectangular microchannels with a prescribed uniform wall heat flux in the slip-flow regime and observed reductions in the friction coefficient are in the entrance region due to rarefaction effects. In addition, similar works in which usage of microchannels played important roles were published in Qazi Zade et al (2015) and Hamedi et al (2016). Farzaneh et al (2016) investigated convective cooling of a square shape piece using dendritic microchannels with/without loops within the platform of constructal theory.…”

Start-Up Electroosmotic Flow of Multi-Layer Immiscible Maxwell Fluids in a Slit Microchannel

“…This transport method has been theoretically studied since many years ago in small channels with Newtonian fluids, as the early works carried out by Burgreen and Nakache [ 6 ] and Rice and Whitehead [ 7 ]. Since then and until now, the scientific community has continued studies on the electroosmotic flow behavior using Newtonian [ 8 , 9 , 10 , 11 , 12 ] and non-Newtonian fluids [ 13 , 14 , 15 , 16 , 17 , 18 , 19 ], addressing emerging issues regarding the rheology of the fluids and ionic concentrations, channel geometry, wall zeta potentials effects, boundary slip effects, among other topics, and their implications on the flow characteristics.…”

Mixing Enhancement of Electroosmotic Flow in Microchannels under DC and AC Electric Field

“…The lab-on-a-chip (LOC) device is an important technology in the development of micro-totalanalysis-system (Nekoubin, 2018;Hamedi et al, 2016). The basic functions of biological or chemical laboratories can be downsized to a few centimeters of chips to simplify the analytical process, reduce consumption of samples and improve the accuracy of analysis (Stone et al, 2004).…”