R. I. Khalilov, A. D. Mamykin, R. S. Okatev, I. V. Kolesnichenko

THE IMPACT OF FLOW INDUCED BY ROTATING MAGNETIC FIELDS ON PROCESSES IN A MOLTEN CONDUCTIVE MEDIUM

This paper studies a method of stirring liquid metal by the action of rotating magnetic fields using two ring inductors placed next to each other. These inductors generate magnetic fields rotating in opposite directions. The aim of this study is numerical investigation of the generated fluid flow and its impact on the homogenization of a two-phase medium, as well as on the crystallization process. The impact of these electromagnetic forces proves to cause the generation of intense poloidal flow component. The arising flow is accompanied by oscillatory motion of vortex structures and their interaction resulting in effective mixing of the liquid metal. The moderate values of the force parameter have been found to lead to the most homogeneous medium under stirring. Under non-stationary action, the force parameter modulations in a certain frequency range have practically no effect on the homogeneity occurrence time and the homogeneity value. The positive effect of stirring by magnetic fields of complex topology on the rate and homogeneity of metal solidification is stated. The obtained results are relevant for improving the quality of foundry ingots.

Acknowledgment: The work was performed according to government budget plan No. 122030200191-9 and supported by grants from the RFBR and Perm Krai, project No. 20-48-596015.

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