Non-Newtonian Casson pulsatile fluid flow influenced by Lorentz force in a porous channel with multiple constrictions: A numerical study

Abstract

In this paper, we investigate non-Newtonian Casson fluid flow with pulsation in a channel having symmetrical constriction bumps on the upper and lower walls. The medium is assumed to be porous, following Darcy’s law. The fluid is modeled as electrically low conducting, and the pulsatile flow is subjected to a transverse magnetic field of uniform strength to study the impact of the resulting Lorentz force. We transform the mathematical model using the vorticity-stream function form for obtaining the solution. We analyze influence of the Hartman, Strouhal, Casson fluid, and porosity parameters on various flow profiles. It is revealed that the region of flow separation in the wake of a constriction bump tends to vanish with increasing the magnetic field parameter as well as Casson fluid parameter. The wall shear stress has higher values at the first constriction bump than that at the second constriction bump on a wall. It is also noticed that wall shear stress decreases with increasing the value of the porosity parameter during the pulsation cycle.