Numerical Simulation of the Flow Field in an Ultrahigh-Speed Continuous Casting Billet Mold

Abstract

Ultrahigh-speed continuous casting is a critical element in achieving high-efficiency continuous casting. In the present work, a three-dimensional model of a 160 mm × 160 mm billet ultrahigh-speed continuous casting mold was developed for use in studying the influences of different casting parameters on molten steel flow. The results showed that the flow pattern in the mold was not associated with its casting speeds, submerged entry nozzle (SEN) immersion depths, or inner diameters. Variation in casting speeds significantly affected the liquid level of the steel–slag interface. Its liquid level fluctuation was reasonable at an SEN immersion depth of 80 mm. Its impact depth reached the shallowest point, which was conducive to upward movement within high-velocity and high-temperature regions, and accelerated the floating of non-metallic inclusions. Expanding the inner diameter of the SEN could effectively weaken the initial kinetic energy of the jet. However, it may cause a deeper impact depth and a degree of upward movement in the raceway, which exhibited the shallowest impact depth in the jet and the most reasonable behavior of molten steel at a liquid level for which the inner diameter of the SEN was 40 mm.

Numerical Simulation of Fluid Flow, Solidification, and Solute Distribution in Billets under Combined Mold and Final Electromagnetic Stirring

“…𝒄 𝒄 𝟎 (33) where 𝒄 represents the carbon concentration at the point, wt.%. 𝒄 𝟎 stands for the average carbon concentration at each sampling point in the experiment and is the initial carbon concentration in the molten steel in the simulation, wt.%.…”

“…This creates a smaller circulation around the meniscus, solidifying shell, and outer wall of the SEN. This region exhibits poorer fluidity compared to the area below the SEN, constituting a typical "dead zone" beneath the meniscus [33]. Most of the molten steel flows along the casting direction at the bottom of the circulation formed by the impact of the jet.…”