Experimentally validated coupled modelling of the heat transfer processes of electromagnetically driven flow within a cold-crucible induction furnace

Abstract

This paper presents a coupled numerical study of the thermal processes that occur in the vacuum induction furnace with a cold crucible. In this furnace type, the high quality metals like titanium are thermally processed. The perspective aim of this work is to improve crucible structure to reduce the skull volume on the basis of the validated numerical model. In the developed code, the two-way coupling of the electromagnetic and thermal phenomena is employed to mainly predict the shape and temperature of the melt free surface. Both these parameters were measured using contactless methods with infrared and high-speed cameras. Moreover, the shape and mass of the skull was also predicted and compared with the experimental data. The numerical simulations were performed for a repeating part of the full 3-D domain for three different portions of the titanium charge. In the coupling transient procedure, the electromagnetic submodel produced a field of power losses generated within the molten metal space, while the thermal model was responsible to generate the free surface shape. The data transfer after each time step was performed from the initial flat free surface until the monitored data became constant as observed during the tests in the lab. The results showed that compared shape and the temperature were predicted with a quite satisfactory accuracy.