Abstract
In the last decades, electromagnetic braking (EMBr) systems become a powerful tool to dampen possible jet oscillations in the continuous casting mold. Further studies showed that if a EMBr is not positioned correctly, it can induce flow oscillations. Hence, the design of these braking systems can be promoted by adequate CFD simulations. In most cases, unsteady RANS simulations (URANS) are sufficient to resolve low-frequency, large-scale oscillations of these MHD flows. Alternatively, Large Eddy Simulations (LES) may also resolve important details of the turbulence. However, since they require much finer computational grids, the computational costs are much higher. A bridge between both approaches are hybrid methods like the Scale Adaptive Simulation (SAS). In this study, we compare the performance of SAS with URANS and LES. Results are validated in detail by comparison with data from a Ruler-EMBr model experiment.
Acknowledgments
The research is supported by the Helmholtz Association of German Research Centres e.V. in form of the LIMTECH Alliance project C3: Modeling of steel casting. This support is sincerely acknowledged by the authors. The help through the interdisciplinary work in the Helmholtz LIMTECH research alliance is gratefully acknowledged as well. The authors are grateful to Klaus Timmel and Sven Eckert (Helmholtz–Zentrum Dresden–Rossendorf) for providing the velocity measurement database. Further a special thanks is given to Thomas Wondrak (Helmholtz–Zentrum Dresden–Rossendorf) and Martin Niemann (Technische Universität Dresden) for fruitful discussions regarding the subject.
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