An attempt has been made to study the Dufour effect on a transient MHD convective flow past a uniformly moving porous plate in presence of a heat sink when suction velocity as well as free stream velocity varies periodically with time. A uniform magnetic field is applied normal to the plate. The plate is assumed to move with a constant velocity in the direction of the fluid flow. The equations governing the flow, heat and mass transfer characteristics are solved analytically using perturbation technique. The profiles of the dimensionless velocity, temperature, concentration as well as skin friction, Nusselt number and Sherwood number at the plate are demonstrated graphically for various values of the parameters involved in the problem and the results are discussed.

MHD, chemical reaction, porous medium, Dufour effect, radiation absorption.