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Aims to present recent activities in experimental investigations and numerical modelling of the induction cold crucible installation.

Temperature and velocity measurements using thermocouples and electromagnetic velocity probes were performed in aluminium melt which was used as a model melt. Measured temperature field and flow pattern were compared with transient 3D calculations based on large eddy simulation (LES) turbulence modelling scheme. Numerical results are in good coincidence with the experimental data.

The modelling results show that only 3D transient LES is able to model correctly these heat and mass transfer processes.

It is revealed that transient 3D modelling provides a universal tool for simulating convective heat and mass transfer processes in the entire melt influenced by large scale instabilities in the recirculating flows, which contain several main vortexes of the mean flow.

Experimental investigations of the turbulent flow velocities measured in the melt of experimental induction furnaces show, that beside the intensive local turbulence pulsations, macroscopic low‐frequency oscillations of the recirculated toroidal main flow eddies play an important role in the heat and mass exchange processes. Traditional numerical calculations of the flow and transfer processes, based on wide spread commercial codes using various modifications of the k‐ε turbulence model show that these models do not take into account the low‐frequency oscillations of the melt flow and the calculated temperature and concentration distributions in the melt essentially differs from experimental results. Therefore, the melt flow dynamics in an induction crucible furnace was numerically simulated with help of transient three‐dimensional calculations using the large eddy simulation turbulence model. This leads to a good agreement between calculated and measured periods of low‐frequency oscillations and heat and mass transfer between the toroidal flow eddies.

The purpose of this paper is to describe how electromagnetic stirring during continuous casting of ferrous and non‐ferrous metals is applied in order to increase the homogeneity and the material properties by improving the grain refinement in the solidification process. The fluid flow and thermal modeling was performed for studying the metal wire pulling process, where melt is being stirred at the solidification front (SF) by electromagnetic forces. Transient simulation has been carried out in order to investigate the periodical character of the process.

The numerical analysis was performed in 2D utilizing the rotational symmetry of the problem. First the electromagnetic fields were estimated using FEM and were subsequently exported as source terms in a coupled thermal and flow simulation with FVM.

The presented numerical model estimated the most suitable position between the stirring coil and the SF to achieve high flow velocities which improve the grain refinement process.

This work enables estimation of the melt solidification in an electromagnetic stirred continuous casting process with oscillating pull velocities.

The purpose of this paper is to introduce a numerical calculation method to study the uniformity of the magnetic field in a cold crucible used for directional solidification (DS) and provide information for designing a cold crucible that can induce a uniform magnetic field.

To obtain the characteristics of the magnetic field in a cold crucible and its influence on the directional solidification processing, based on experimental verification, 3‐D finite element (FE) models with different crucible configuration‐elements and power parameters were established to study the uniformity of the magnetic field in a cold crucible. In addition, different TiAl ingots were directionally solidified with different cold crucibles, and the solid/liquid (S/L) interfaced were examined to investigate the effect of the magnetic field on the macrostructure of those ingots.

The uniformity of the magnetic field in a given domain can be quantitatively analyzed by statistical methods. Numerical calculation results showed that the uniformity of the magnetic field can be improved by optimizing the crucible configuration and adopting lower frequency. Better uniformity of the magnetic field in a cold crucible is beneficial to directional solidification.

The calculation of the uniformity of the magnetic field is proposed as a method for quantitative study of the distribution characteristics of the magnetic field in a cold crucible. The relationship between the S/L interfaces of TiAl ingots and the uniformity of the magnetic field is initially characterised; additionally, techniques for improving the uniformity of the magnetic field in a cold crucible are suggested.

Heating with a low-frequency induction is a key phenomenon in a process dedicated to the treatment of nuclear wastes. This paper aims to present a step of the numerical model being developed to study this process.

A hydrodynamic model for the processing of a liquid charge consisting of a metallic phase and a dielectric one is developed based on a volume of fluid (VOF) approach coupled with electromagnetic calculations. The latter allows one to calculate the distribution of the Joule heating in the setup and radiative heat exchange inside the crucible is accounted with a surface-to-surface (S2S) model coupled with VOF.

Numerical results are compared with the measures obtained on the prototype of the process. The results are in good agreement but the model needs to be improved to consider the varying viscosity of the glass.

The usage of a S2S radiation model coupled to the VOF model is not common for studies of materials melted by electromagnetic induction. This paper demonstrates the feasibility of this approach.

To provide a selective bibliography for researchers and graduate students who have an interest in induction processes applied to the electromagnetic processing of materials.

The objective is to provide references that identify seminal, early work, and references that represent the current state of the art. References are listed in categories that cover the broad range of induction modeling and application issues.

A brief overview of the key areas in induction processing of materials is provided, but greater emphasis and space is devoted to the references provided.

The middle years of each topic area are not covered.

A very comprehensive coverage of material is provided to those with an interest in induction processing of materials.

This paper fulfils an identified information/resources need.

The purpose of present investigation is to analyze the in-mold electromagnetic stirring (M-EMS) process and the effect of stirrer frequency on fluid flow and solidification in a continuous casting billet caster mold.

A hybrid approach involving finite element and finite volume method has been used for the study. Finite element model is used to calculate time variable magnetic field, which is further coupled with fluid flow and solidification equations for magneto-hydrodynamic analysis with finite volume model.

Results show that though superheat given to steel before its entry into the mold is quickly removed, solid shell formation is delayed by the use of M-EMS. Final solid shell thickness, however, is slightly reduced. Increase in frequency is found to increase the magnetic flux density and tangential velocity of liquid steel and decrease in diameter of liquid core.

The work is of great industrial relevance. The model may be used to design industrial setup of in-mold electromagnetic stirrer and process could be analyzed and optimized numerically.

The paper evaluates the influence of M-EMS and its frequency on solidification and flow behavior in the continuous casting mold. The iso-surface temperatures from pouring temperature to liquidus temperature inside the mold have been shown. The findings may be useful for the steelmakers to reduce the defect in continuous casting.

Aims to present recent activities in numerical modeling of cold crucible melting process.

3D numerical analysis was used for electromagnetic problem and 3D large eddy simulation (LES) method was applied for fluid flow modeling.

The comparative modeling shows, that higher H/D ratio of the melt is more efficient when total power consumption is considered, but this advantage is held back by higher heat losses through the crucible walls. Also, calculations reveal that lower frequencies, which are energetically less effective, provide better mixing of the melt.

3D electromagnetic model, which allows to take into account non‐symmetrical distribution of Joule heat sources, together with transient LES fluid flow simulation gives the opportunity of accurate prediction of temperature distribution in the melt.

The purpose of this paper is to present in‐depth numerical modelling of heat and mass exchange in industrial induction channel furnace (ICF).

The turbulent heat and mass exchange in the melt is calculated using a three‐dimensional (3D) electromagnetic model and a 3D transient large eddy simulation method. The simulation model has been verified by flow velocity and temperature measurements, which were carried out using an industrial sized channel inductor operating with Wood's metal as a low temperature model melt.

The ICF is well‐established for melting, holding and casting in the metallurgical industry. But there are still open questions regarding the heat and mass exchange in the inductor channel itself and between the channel and the melt bath. Different new designed channel geometries have been investigated numerically in order to find an optimized shape of the channel, which leads to an improved heat and mass transfer.

Long‐term computations for the industrial ICF have been performed. Low frequency oscillations of the temperature maximum and its position in the ICF channel are considered.

Aims to present recent activities in numerical modeling of turbulent transport processes in induction crucible furnace.

3D large eddy simulation (LES) method was applied for fluid flow modeling in a cylindrical container and transport of 30,000 particles was investigated with Lagrangian approach.

Particle accumulation near the side crucible boundary is determined mainly by the ρ_p/ρ ratio and according to the presented results. Particle settling velocity is of the same order as characteristic melt flow velocity. Particle concentration homogenization time depends on the internal flow regime. Separate particle tracks introduce very intensive mass exchange between the different parts of the melt in the whole volume of the crucible.

Transient simulation of particle transport together with LES fluid flow simulation gives the opportunity of accurate prediction of admixture concentartion distribution in the melt.