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This paper presents entropy generation analysis for stagnation point flow in a porous medium over a permeable stretching surface with heat generation/absorption and convective boundary condition. We have used Von Karman transformations to transform the governing equations into ordinary differential equations.Thevelocity, temperature and concentration profiles obtained using the Homotopy Analysis Method. The HAM is a valid mathematical tool for most of non-linear problems in science and engineering. Finally we have computed the entropy generation number. The effect of the Prandtl number, Brinkman number, Reynolds number, suction/injection parameter, Biot number, Lewis number, Brownian motion parameter, thermophoresisparameterand constant parameters on velocity, concentration and temperature profiles are analyzed. Moreover the influences of the Reynolds number and Brinkman number on the entropy generation are presented.The entropy generation number increases with increasing the Brinkman and Reynolds number.

This paper looks at the series solutions of three dimensional boundary layer flow. An Oldroyd-B fluid with variable thermal conductivity is considered. The flow is induced due to stretching of a surface. Analysis has been carried out in the presence of heat generation/absorption. Homotopy analysis is implemented in developing the series solutions to the governing flow and energy equations. Graphs are presented and discussed for various parameters of interest. Comparison of present study with the existing limiting solution is shown and examined.

We investigate the Cattaneo-Christov heat flux model for a two-dimensional laminar boundary layer flow of an incompressible Oldroyd-B fluid over a linearly stretching sheet. Mathematical formulation of the boundary layer problems is given. The nonlinear partial differential equations are converted into the ordinary differential equations using similarity transformations. The dimensionless velocity and temperature profiles are obtained through optimal homotopy analysis method (OHAM). The influences of the physical parameters on the velocity and the temperature are pointed out. The results show that the temperature and the thermal boundary layer thickness are smaller in the Cattaneo-Christov heat flux model than those in the Fourier's law of heat conduction.