Entropy Analysis for Unsteady MHD Boundary Layer Flow and Heat Transfer of Casson Fluid over a Stretching Sheet

Mohamed Ahmed MANSOUR, Abd Elnaser Sobhy Mohamed MAHDY, Sameh Elsayed AHMED, Shadia Saber MOHAMED


This paper investigates the entropy generation analysis of the unsteady two-dimensional magnetohydrodynamic (MHD) flow of electrically conducting non-Newtonian Casson fluid and heat transfer towards a stretching sheet in the presence of uniform transverse magnetic field with viscous dissipation and Joule heating effects. Using similarity solutions, the governing partial differential equations are transformed into ordinary differential equations and then solved numerically by MATLAB function bvp4c. The results of the present study indicate that the flow and temperature fields are significantly influenced by unsteadiness parameter Casson parameter , magnetic parameter  Prandtl number and Eckert number  It is found that the fluid velocity initially decreases with increase in the unsteadiness parameter and that temperature decreases significantly due to the unsteadiness parameter. Also, the effect of increasing values of the Casson parameter  is to suppress the velocity field and the temperature distributions. The influences of the same parameters, as well as the Reynolds number and the Brinkman number on the entropy generation, are also discussed.


Entropy, MHD, Casson fluid, stretching sheet, viscous dissipation

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Last updated: 12 August 2019