Copyright © 2012 Sohail Nadeem et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Abstract
Mathematical model for the peristaltic flow of chyme in small intestine along with inserted endoscope is considered. Here, chyme is treated as Williamson fluid,
and the flow is considered between the annular region formed by two concentric tubes (i.e., outer
tube as small intestine and inner tube as endoscope). Flow is induced by two sinusoidal peristaltic
waves of different wave lengths, traveling down the intestinal wall with the same speed. The
governing equations of Williamson fluid in cylindrical coordinates have been modeled. The resulting
nonlinear momentum equations are simplified using long wavelength and low Reynolds number
approximations. The resulting problem is solved using regular perturbation method in terms of
a variant of Weissenberg number . The numerical solution of the problem is also computed by
using shooting method, and comparison of results of both solutions for velocity field is presented.
The expressions for axial velocity, frictional force, pressure rise, stream function, and axial pressure gradient are obtained, and the effects of various emerging parameters on the flow characteristics are illustrated graphically. Furthermore, the streamlines pattern is plotted, and it is observed that trapping occurs, and the size of the trapped bolus varies with varying embedded flow parameters.