The three-dimensional time-dependent flow of silicon melt in an electromagnetic Czochralski system was numerically investigated. Two different types of electrodes were used in the mathematical modeling to determine the mechanisms of heat and oxygen transfer in the melt. The results showed that electromagnetic force in the azimuthal direction suppressed natural convection due to centrifugal force. It was also shown that heat and oxygen transfer from a crucible wall to the solid-liquid interface was enhanced due to off-centered vortices. (C) 2002 Elsevier Science B.V. All rights reserved.