Journal of Theoretical
and Applied Mechanics
51, 1, pp. 25-38, Warsaw 2013
MHD flow and heat transfer of a micropolar fluid over a stretchable disk
A numerical study of an axisymmetric steady laminar incompressible flow of an electrically conducting micropolar fluid over a stretchable disk is carried out when the fluid is subjected to an external transverse magnetic field. The governing nonlinear equations of motion are transformed into a dimensionless form through Von Karman's logic similarity functions. An algorithm based on a finite difference scheme is used to solve the reduced coupled nonlinear ordinary differential equations with the associated boundary conditions. Effects of the micropolar parameters, the magnetic parameter and the Prandtl number on the flow velocity and temperature distribution are discussed. Investigations predict that the heat transfer rate at the surface of the disk increases with an increase in the values of micropolar parameters. The magnetic field enhances the shear and couple stresses. The shear stress factor is lower for micropolar fluids as compared to Newtonian fluids, which may be beneficial in flow and heat control of polymeric processing.
Keywords: magnetohydrodynamics (MHD); micropolar fluids; heat transfer; stretchable disk