A parametric study to investigate the effect of radiation on a two dimensional free convective MHD flow of a viscous incompressible and electrically conducting fluid through a channel bounded by a long vertical wavy wall and a parallel flat wall with Soret and Dufour effects is presented. A uniform magnetic field is assumed to be applied normal to the flat wall. The equation governing fluid flow is solved analytically subject to the relevant boundary conditions. It is assumed that the solution consists of two parts, a mean part and a perturbed part. The long wave approximation has been used to obtain the solution of the perturbed part and to solve the mean part, the well known approximation used by Ostrach [1] has been applied. The perturbed part of the solution is the contribution from the waviness of the wall. The expressions for zeroth and first order velocity, temperature, concentration and skin friction and the rates of heat and mass transfer at the walls are obtained. Some of the results indicating the influence of radiation, Soret and Dufour effects on the above fields have been presented graphically.

MHD, free convective, radiation effect, Soret effect, Dufour effect.