Abstract
This paper presents a numerical study for the peristaltic flow characteristics of a Sisko fluid in a symmetric or asymmetric channel. The fluid is assumed to be electrically conducting in the presence of a uniform magnetic field. The mathematical formulation consisting of nonlinear governing equations and boundary conditions is first casted into a dimensionless form. The resulting equation for long wavelength and low Reynolds number assumptions is then numerically solved using an iterative method. The behaviors of the shear-thinning and shear-thickening non-Newtonian Sisko fluids are compared with those of the corresponding Newtonian fluid. Velocity distributions, pressure gradients, shear stresses as well as streamline pattern with respect to various material parameters and phase differences of the wall peristalsis are investigated. Some typical characteristics of peristaltic motion, e.g. pumping against a pressure rise and trapping phenomena etc. are observed from the numerical results and discussed. (C) 2007 Elsevier B.V. All rights reserved.