Convective flows of micropolar fluids from radiate isothermal porous surfaces with viscous dissipation and Joule heating

In this study, the steady laminar free-forced convective flow and heat transfer of micropolar fluids past a vertical radiate isothermal permeable surface with viscous dissipation and joule heating is investigated numerically. The local similarity solutions for the flow, microrotation (angular velocity) and heat transfer characteristics are illustrated graphically for various material parameters. The effects of the pertinent parameters on the local skin friction coefficient, plate couple stress and the rate of heat transfer are also calculated. It was shown that micropolar fluids presented lower viscous drag and heat transfer values than those of the Newtonian fluids. The effect of radiation on the rate of heat transfer in a weakly concentrated micropolar fluid is higher than a strongly concentrated micropolar fluid. Results also show that full radiation has significant effect on the rate of heat transfer compared to the linear radiation. (C) 2008 Elsevier B.V. All rights reserved.