Abstract
The dissolution of alumina in cryolite is a complex process, and better understanding is needed to ensure stable cell conditions and high energy efficiency. Additions of cold powder result in freezing of bath that hinders dissolution, and creation of rafts. The current work aims to develop and demonstrate a CFD framework in OpenFOAM for freezing of bath on a fed dose of alumina, based on the volume of fluid (VOF) method, where appropriate source- and sink terms are applied. Essential features have been verified by comparison with a Stefan problem, while simulating the dose as a floating rigid object demonstrate that a larger layer of freeze increase the dam** of its movement. When simulating the dose as an immiscible fluid, spreading will hinder enough freeze to be formed around the dose. Hence, the added source terms behave as intended, but improvements on the alumina-bath interactions are needed.
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Acknowledgements
The current work has been funded by SFI Metal Production (Centre for Research-based Innovation, 237738). The authors gratefully acknowledge the financial support from the Research Council of Norway and partners of the center.
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Gylver, S.E., Einarsrud, K.E. (2023). CFD Modelling of Solidification and Melting of Bath During Raft Formation. In: Broek, S. (eds) Light Metals 2023. TMS 2023. The Minerals, Metals & Materials Series. Springer, Cham. https://doi.org/10.1007/978-3-031-22532-1_92
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DOI: https://doi.org/10.1007/978-3-031-22532-1_92
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