Experimental and numerical investigations of the temperature field and melt flow in the induction furnace with cold crucible

Abstract

Comprehensive knowledge of the complicated physical behavior of the induction furnace with cold crucible (IFCC) is required to utilize the advantages of this melting aggregate in melting and casting chemically high-reactive materials, like titanium-aluminides (TiAl). Practical experiences show that the overheating temperature of the melt is decisive for the quality of the cast products. Therefore, a systematic analysis of the electromagnetic and in particular, the hydrodynamic and thermal behavior of the IFCC is carried out. The examinations of the influence of the construction elements as well as the process parameters on the temperature field and finally the overheating temperature in the IFCC are performed using specifically developed numerical models. The evaluation of the numerical results is done by experimental investigations, where aluminum serves as a model melt for the experimental determination of the thermal and hydrodynamic field of the melt. The analysis of the influence of construction-elements on the overheating temperature is focused on the design of the crucible wall and the crucible bottom, on the height-diameter ratio of the crucible and on the axial inductor position. The inductor current, the operation frequency and the crucible filling level are found to be very important for reaching a high overheating temperature.

Numerical Modeling of Flow Conditions during Steel Filtration Experiments

“…[6,7] The stirring processes and the melt flow in an ICF have been studied both numerically and experimentally for a long time. [8][9][10][11][12][13][14] Baake et al [8] demonstrated that the predictions, obtained with the standard k-e turbulence model are able to provide a good agreement with the experimentally determined time-averaged velocity field. However, the low-frequency pulsations in the velocity, which occur in the region between the main long-term vortices, prove difficult to be captured by adopting this model.…”

“…The Large eddy simulation (LES) was found to be a good variant for more accurate predication of the low-frequency fluctuations and the temperature distribution in the melt. [9][10][11][12] Schwarze et al [14] performed an unsteady Reynolds averaged Navier-Stokes simulation (URANS) in order to investigate the turbulent melt flow in an ICF adopting the Reynolds stress turbulence model. Using this turbulence model, the predicted results showed the presence of the large flow structure with low frequency fluctuations.…”

Numerical Investigation of Filtration Influenced by Microscale CO Bubbles in Steel Melt

“…[6,7] Many numerical and experimental investigations have been carried out to predict melt flow in an ICF. [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23] Numerous authors have reported that the large eddy simulation (LES) produces fairly accurate heat and mass transfer predictions, compared with the unsteady Reynolds-averaged Navier-Stokes (URANS) simulations. [9][10][11][12][13] In addition to simulating and studying the melt flow, other authors have investigated inclusions transport in an ICF.…”

Thermal and Hydrodynamic Analysis of the Melting Process in the Cold Crucible Using 3D Modeling

“…Practical experiences show that the overheating temperature of the entire melt, which is determined by the electromagnetic, hydrodynamic and thermal process factors, is one of the key parameters of this technological process. Due to its importance for modern industry it has become the subject for numerical modeling [1][2][3]. The task of optimising melt overheating faces the challenge of finding optimal combination of crucible height to diameter ratio, number of inductor turns and crucible sections, current strength and frequency.…”