Abstract: The H² funnel-shaped mold for FTSC process can produce the slab with width of 860 mm~1 730 mm.The study on molten steel flow,heat transfer and solidification behavior of H² mold with different widths can help to make a better understanding about metallurgical behaviors in the H² mold and provide guidance for equipment manufacturing and process parameters optimization.Numerical simulation technique is employed to study the fluid flow,heat transfer and solidification behaviors in the mold with the casting speed of 4.5 m/min and the H² mold widths of 900 mm,1 300 mm,and 1 700 mm.The results show that with the increase in mold width,the flow field has noticeable change,and the wave fluctuation at the free surface near the SEN intensifies.Under the conditions of different widths of mold,the differences in surface temperature and solidified shell thickness of the slab at the exit of the mold are mainly reflected near the narrow face.