Abstract: During the continuous casting process, the formation and growth of the solidified shell directly determine production safety and product quality, while the flow behavior of molten steel is a critical factor influencing heat transfer during initial solidification and the stability of the solidification front. Therefore, a three-dimensional coupled mathematical model of flow, heat transfer, and solidification in the continuous casting mold was established. The effects of argon flow rate and casting speed on the flow field, temperature distribution, and shell thickness within the mold were systematically simulated. The results indicate that the molten steel exhibits a double-roll flow pattern in the mold. The main jet impinges on the narrow face and forms recirculation flows, leading to significant differences in heat transfer intensity across different regions. At the narrow face, the thickness of the solidified shell and the flow velocity of molten steel at the solidification front show a "first decrease, then increase" trend, demonstrating a clear quantitative correlation. In contrast, at the wide face, due to the upper recirculation flow and intense turbulent mixing near the center, no stable correlation is observed between shell thickness and flow velocity. The findings of this study can provide a theoretical basis for optimizing continuous casting parameters and controlling solidification front stability.

Key words: continuous casting; mold; molten steel flow; solidified shell; temperature distribution; argon flow rate; casting speed