## THERMAL SCIENCE

International Scientific Journal

### MHD FREE CONVECTION-RADIATION INTERACTION ALONG A VERTICAL SURFACE EMBEDDED IN DARCIAN POROUS MEDIUM IN PRESENCE OF SORET AND DUFOUR'S EFFECTS

**ABSTRACT**

The effects of thermal radiation and magnetic field on heat and mass transfer characteristics of natural convection about a vertical surface embedded in a saturated Darcian porous medium has been investigated taking into account the Soret and Dufour effects. The Rosseland approximation for the radiative heat flux is used in the energy equation. It is found that the similarity solution exists in the present case. The resulting set of coupled non-linear ordinary differential equations is solved numerically using shooting technique. Dimensionless velocity, temperature, and concentration profiles are presented graphically for various values of radiation parameter and the Nusselt and Sherwood numbers are tabulated for different values of the involved parameters. It is found that the Nusselt number increases and Sherwood number decreases as the radiation parameter increases but both the Nusselt number and Sherwood number decrease as the magnetic field parameter increases.

**KEYWORDS**

PAPER SUBMITTED: 2008-11-19

PAPER REVISED: 2009-04-05

PAPER ACCEPTED: 2009-04-14

**THERMAL SCIENCE** YEAR

**2010**, VOLUME

**14**, ISSUE

**Issue 1**, PAGES [137 - 145]

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