An mathematical model for nozzle with three ports in continuous casting thin slab was established by coupling thermo-flow method based on mass equation

movement equation and energy equation of liquid steel in mould to simulate velocity field and temperature field in liquid steel. The main features of flow field and temperature field in nozzle with three ports during continuous casting were described to analyze effects on quality of billet. Meanwhile

the effects of immersing depth of nozzle and casting speed on the meniscus shape of liquid steel were understood to optimize flow field and pouring parameters of liquid steel in mould.