Study on the Asymmetric Fluid Flow in the Continuous Casting Mold

Abstract

It is very important to understand flow patterns within the continuous casting mold because they have a significant impact on product quality. Water model experiment and numerical simulation conducted to identify the fluid flow pattern in the steel slab continuous casting mold. The fluid flow pattern in the mold is not steady but instead an oscillatory flow with a specific oscillation frequencies. We identified the physical origins of various specific oscillation frequencies, and confirmed through experimentation and simulation that each frequency is related to the cross flow and injection stream oscillation. Moreover, the degree of oscillation at each frequency appears differently depending on the location within the mold, and is shown to have a effect near the mold wall. Water model experiment was conducted to observe the surface fluctuation corresponding to different port angles of the submerged entry nozzle in the steel slab continuous casting mold. When the port angle has low values, the amplitude of the surface fluctuation is relatively larger than for higher angles. We demonstrate that these phenomena are related to the fluid flow patterns in the mold by numerical simulation. Fluid flow patterns are asymmetric and unsteady for low port angles, with repetition of vortex nucleation and annihilation. However, fluid flow patterns become symmetric with increased SEN port angles. These results not only provide a better understanding of complex oscillatory flow patterns, but also provide a method to obtain a stabilized surface within the mold.