Hermite–Padé approach to thermal radiation effect on inherent irreversibility in a variable viscosity channel flow

This present work examines the effect of thermal radiation on inherent irreversibility in the flow of a variable viscosity optically thin fluid through a channel with isothermal walls. First and Second Laws of thermodynamics are employed in order to analyze the problem. The simplified governing non-linear equations are solved analytically using a perturbation method coupled with a special type of Hermite–Padé semi-analytical technique. Expressions for dimensionless velocity and temperature, thermal criticality conditions and entropy generation number are obtained. Both numerical and graphical results are presented and discussed quantitatively with respect to various parameters embedded in the problem.