peristaltic flow of phan-thien-tanner fluid in an asymmetric channel with porous medium

This paper deals with peristaltic transport of phan-thien-tanner fluid in an asymmetric channel induced by sinusoidal peristaltic waves traveling down the flexible walls of the channel. the flow is investigated in a wave frame of reference moving with the velocity of the waveby using the long wavelength and low reynolds number approximations.the nonlinear governing equations are solved employing a perturbation method by choosing we as the perturbation parameter. the expressions for velocity, stream function and pressure gradient are obtained. the features of the flow characteristics are analyzed through graphs and the obtained results are discussed in detail. it is noticed that the peristaltic pumping gets reduced due to an increase in the phase difference of the traveling waves. it is also observed that the size of the trapping bolus is a decreasing function of the permeability parameter and the weissenberg number. furthermore, the results obtained for the flow characteristics reveal many interesting behaviors that warrant further study on the non- newtonian fluid phenomena, especially the peristaltic flow phenomena.