Computational modelling of non-Newtonian effects on flow in channels with moving wall indentations

Non-Newtonian effects in a channel with moving wall indentations are assess ed numerically by a finite volume method for solving the unsteady incompres sible Navier-Stokes equations and using a power-law model exhibiting shear thinning viscosity and Casson's model as the constitutive equations for the non-Newtonian fluid. The computations show that for a non-Newtonian fluid, there are differences in the velocity profiles and in the structure and si ze of the reversed flow regions as compared with the corresponding Newtonia n fluid. The comparison of non-Newtonian and Newtonian wall shear stress re veals a slight decrease in the magnitude on the average for the non-Newtoni an case, eventually resulting in the strength of the "wave train" being sli ghtly weaker than those corresponding to a Newtonian fluid.