Characterization of the Turbulent Fluid Flow Structures in a Slab Mold with Experimental Measurements and Different Turbulence Models

Abstract

The turbulent flow of liquid steel in a slab mold was characterized using a commercial nozzle through physical water-model experiments and four turbulent models: 𝑘 − 𝜀 Realizable (RKE), Detached Eddy Simulation (DES), Scale-Adaptive Simulation (SAS), and Large Eddy Simulation (LES). The comparison between numerical results and the experimental measurements (using Ultrasound Velocimetry) permitted the characterization of flow structures along a sub meniscus region, (of great importance for flux-dragging phenomena) In general, all four models predict characteristic unsteady state turbulent flows. However, the 𝑘 − 𝜀 Realizable and DES models fail to predict instabilities in the internal flow of the nozzle, overpredicting sub-meniscus velocities in the mold. On the other hand, the SAS and LES models manage to predict the instabilities and changes in the internal flows inside the nozzles that occur at high frequencies and achieve an excellent agreement with the experimental velocity profiles. With the analysis of the results obtained, it is possible to say that the SAS model produces performances like those of the LES model with less computing effort and less cost.