Entropy Analysis on Unsteady MHD Flow of Casson Nanofluid over a Stretching Vertical Plate with Thermal Radiation Effect

Abstract

This article proposes to study the entropy analysis on an unsteady magnetohydrodynamic flow of Casson nanofluid and convective heat transfer over a time dependent stretching vertical plate. We have treated Buongiorno’s model to characterize the thermophysical properties of nanofluid. The effect of thermal radiation and viscous dissipation of energy for non-Newtonian nanofluid and the external magnetic field are examined. The set of partial differential equations for time dependent flow of nanofluid are reduced to a system of coupled ODEs by a suitable similarity transformation. These reduced equations are solved by employing the fourth order Runge–Kutta-Fehlberg method along with shooting technique. The flow behavior of non-Newtonian Casson nanofluid, heat transfer characteristics, nanoparticle concentration profiles and entropy analysis have been made to understand the impact of different dimensionless parameters. Furthermore, the expression for dimensionless wall shear stress, heat and mass transfer rate over a heated vertical plate have been investigated. The study shows that entropy generation sharply increases with Casson parameter, whereas it increases near the plate with the thermal radiation. The entropy generation measuring through Bejan number has significant impact in aeronautics propulsion and power engineering to predict the efficient performance of the entire system.