DefinePK

Abstract

A genuine variational principle developed by Gyarmati, in the field of thermodynamics of irreversible processes unifying the theoretical requirements of technical, environmental and biological sciences is employed to study the mixed convection heat transfer about a semi infinite inclined plate in the presence of magnetohydrodynamic (MHD) and thermal radiation effects. The velocity and temperature distributions inside the boundary layer has been considered as a simple polynomial functions and the variational principle is formulated. The Euler-Langrange equations are reduced to coupled polynomial equations in terms of boundary layer thicknesses. The effects of the magnetic parameter (M), the mixed convection parameter (Ri), the angle of inclination (α), the radiation-conduction parameter (Rd), the temperature ratio (θw) and the Prandtl number (Pr) on the velocity and temperature profiles as well as on the skin friction and heat transfer parameters are presented and analyzed. For some specific values of the governing parameters, the results agree very well with those available in the literature. The present study establishes a high accuracy of results obtained by this variational technique.