Numerical study of electromagnetic stirring in a process containing liquid glass and metal

International audienceIn a part of a process currently being developed to compact solid radioactive wastes in packages for long time storage, some metal and some glass are melted in a container by low frequency electromagnetic induction. This paper presents a numerical study performed to analyze the stirring of the liquids, in order to prevent the solidification of the free surface of the glass. The main difficulty for the modeling comes from the strong deformation of the interfaces, produced by the magnetic pressure, which is responsible for the strong coupling between electromagnetism and the fluid flow. The calculation is realized by a parallel coupling between COMSOLMultiphysics for the electromagnetism, and ANSYS Fluent for the three phase (VOF) turbulent flow. A parametric study was conducted on the Joule power in the metal, the frequency, and the quantity of glass in the crucible. Among other things, the results show that the stirring of the glass is stronger for lower frequencies when the quantity of glass is high, because of the reduction of the area of the interface with the air