A theoretical analysis of rotating electromagnetohydrodynamic and electroosmotic transport of couple stress fluid through a microchannel

Abstract The study of bio-fluids in rotating microfluidic platforms is becoming much more significant, hence it is important to discuss the non-Newtonian fluids in such environments. This paper analytically investigates the hydrodynamic characteristics of combined electromagnetohydrodynamic (EMHD) and electroosmotic flow (EOF) transport of non-Newtonian fluid through a rotating microchannel with Navier-slip boundary conditions at the walls. The couple stress fluid model is considered a non-Newtonian fluid in the flow domain. The linearized Poisson-Boltzmann equation is considered inside the electric double layer (EDL). The modified Stokes equation is governed by a combined imposed magnetic and electroosmotic flow field. Analytical expressions are obtained for electrical potential, flow velocity, and volume flow rate in the channel using suitable boundary conditions. The results obtained in this study are compared with those published in the literature from two different perspectives and found excellent matching in both cases. The dependence of rotating electromagnetic flow velocity and flow rates on appropriate parameters is explained. It is found that the rotational flow velocity displays an opposite pattern when the couple stress parameter and electric field intensity parameters are varied due to the influence of channel rotation. It is also found that the secondary flow rate ratio is amplified with the Hartmann number and slip length parameter, due to the stronger impact of the non-Newtonian behaviour than the Newtonian situation on the volume flow rate at a relatively higher rotational value. The findings of this study may aid in the design and analysis of practical thermal micro/nano-equipment for transporting biofluids.