Abstract: The unsteady fluctuation behavior of the slag-metal interface in a slab continuous casting mold was studied using the volume of fluid(VOF)method. The morphology of the meniscus was simulated using the geometric reconstruction scheme. The effects of casting speed， immersion depth and port angle of submerged entry nozzle(SEN) on the interface fluctuation in the mold were studied. The results show that the interface fluctuation is ever changing with time. The fluctuation is small and increases with time at the beginning of the casting. After attaining dynamic steady state， serrated fluctuation phenomenon appears around the SEN. The reason for the serrated fluctuation is the existence of vortices. The fluctuation increases with increasing the casting speed， and decreases with increasing the immersion depth and port angle of the SEN.

Key words: continuous casting mold, unsteady state, VOF method, slag-metal interface, fluctuation