Entropy Generation Analysis for Variable Viscous Couple Stress Fluid Flow through a Channel with Non-Uniform Wall Temperature

Abstract

This article addresses the influence of couple stresses in minimizing of entropy generation rate associated with heat transfer irreversibility in the steady flow of a variable viscous fluid through a channel with a non-uniform wall temperature. The flow is induced by a constant axial pressure gradient applied in the flow direction. It is assumed that the fluid viscosity varies linearly with tem perature. Analytical expressions for the dimensionless equations governing the fluid velocity and temperature are derived and used to obtain expressions for volumetric entropy generation numbers, irreversibility distribution ratio and the Bejan number in the flow field. Plots for different pertinent parameters entering the velocity and temperature fields are displayed and discussed.