Effects of Magnetic Field on Entropy Generation in Flow and Heat Transfer due to a Radially Stretching Surface

We investigate the effects of magnetic field on the entropy generation during fluid flow and heat transfer due to the radially stretching surface. The partial differential equations governing the flow and heat transfer phenomenon are transformed into nonlinear ordinary differential equations by using suitable similarity transformations. These equations are then solved by the homotopy analysis method and the shooting technique. The effects of the magnetic field parameter M and the Prandtl number Pr on velocity and the temperature profiles are presented. Moreover, influence of the magnetic field parameter M and the group parameter Br/Ω on the local entropy generation number Ns as well as the Bejan number Be are inspected. It is observed that the magnetic field is a strong source of entropy production in the considered problem.