MHD flow and heat transfer of an Ostwald–de Waele fluid over an unsteady stretching surface

Abstract

An analysis is carried out to study the effects of variable thermo-physical properties on an unsteady MHD flow and heat transfer of an Ostwald–de Waele fluid over a stretching surface. The thermo-physical properties, namely, viscosity and thermal conductivity of the fluid are assumed to vary with temperature. Using similarity transformation, the governing partial differential equations are converted into coupled, non-linear ordinary differential equations with variable coefficients. The resulting non-linear equations are solved numerically by a second-order finite difference scheme known as the Keller-box method for various values of the pertinent parameters. Also, the numerical results are obtained for special cases and are found to be in good agreement with those of the results available in the literature. Further, the results obtained reveal many interesting behaviors that warrant further study of the equations related to non-Newtonian fluid phenomena, especially the shear-thinning phenomena. Shear thinning reduces the wall shear stress.

Keywords

• Ostwald–de Waele fluid
• MHD flow
• Heat transfer
• Variable fluid properties
• Unsteady stretching surface
• Finite difference method