Numerical Analysis of Magnetic–Fluid–Thermal Multifield Coupling Processes in Electric Fused Magnesia Furnace

Abstract

The production of fused magnesia is a process in which raw materials are melted and recrystallized in the electric-fused magnesia furnace (EFMF). Temperature is the key factor that affects production, but it is difficult to be observed and monitored due to the high internal temperature. Thus, the working current is the standard for workers to judge whether the production process is normal. In order to master heat transfer characteristics in the furnace and accurately control the processes, a three-dimensional mathematical model of coupling the magnetic–fluid–thermal multifield has been established in a six-electrode EFMF. The model also considers the thermal decomposition of magnesium carbonate in the furnace. The phase change of materials is simulated by the solidification and melting model. The results show that the current density and Joule heat are concentrated in the region below the electrode. When the current size increases to 12,500 A, the molten pool begins to be connected. The average wall temperature at the end of the smelting stage is only 317.54 K, which conforms to the reality. The results of this study could provide guidance for practical production.