Peristaltic motion of non-Newtonian fluid with variable liquid properties in a convectively heated nonuniform tube: Rabinowitsch fluid model

This paper investigates the effects of variation in viscosity and thermal conductivity on the peristaltic mechanism of Rabinowitsch fluid through a nonuniform tube. The convective surface conditions and wall properties are taken into account. The governing equations of motion, momentum, and energy are rendered dimensionless and are solved using long wavelength and small Reynolds number approximations. The series solution technique is employed to solve the resulting nonlinear temperature equation. The effects of relevant parameters on physiological quantities of interest are analyzed graphically, and the validation of the present model with the existing literature has been presented through graphs. The outcomes of the study reveal that an increase in the value of variable viscosity and thermal conductivity enhances the velocity and temperature profiles for dilatant, Newtonian, and pseudoplastic fluid models. Further, an increase in the value of variable viscosity enhances the skin friction coefficient and Nusselt number. Moreover, the presence of variable viscosity diminishes the volume of the trapped bolus.