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The inductive skull melting technology has many advantages for melting ofirmovative materials in the field of glasses and oxides.It offers high processing temperatures and the compliance of necessary purities at the same time.Applicable materials are in particular optical glasses,which are applied for lenses,fibers or filters,because the skull melting technology allows high process temperatures and high purities of the final product.In the production of glass materials strong requirements have to be fulfilled regarding the optical characteristics,which are mainly defined and influenced by the melting of the raw material and the following terming process.An unsolved problem in the melting process of glasses and oxides using the inductive skull melting technology was in the past the unknown heat and mass transfer in the melt because temperature and melt flow measurements in the melt are practically impossible due to the high tempera~tres.On the other hand the temperature and velocity distribution in the melt is very important regarding the safety of the melting process,the process control for producing the required properties of the material or the further development of skull melting installations.The paper describes a new numerical model which is able to simulate the instationary 3D melt flow of glasses and oxides.The numerical model takes into account electromagnetic,convection and Marangoni forces.By this a comprehensive view of the hidden processes in the practical experiments could be obtained.By means of the new numerical model different glass and oxide melting processes were simulated and the results were compared with experimental results.The comparisons show first of all a very good agreement between experimental and numerical results at the melt surfaces.Additionally the numerical results allow to look much deeper inside the melt and show interesting new effects of the heat and mass transfer below the melt surface which were unknown before.
The inductive skull melting technology has many advantages for melting ofirmovative materials in the field of glasses and oxides. It offers high processing temperatures and the compliance of necessary purities at the same time. Applicable materials are in particular optical glasses, which are applied for lenses, fibers or filters, because the skull melting technology allows high process temperatures and high purities of the final product. the production of glass materials strong requirements have to be fulfilled regarding the optical characteristics, which are mainly defined and influenced by the melting of the raw material and the following terming process. An unsolved problem in the melting process of glasses and oxides using the inductive skull melting technology was in the past the unknown heat and mass transfer in the melt due temperature and melt flow measurements in the melt are practically impossible due to the high tempera ~ tres.On the other hand the temperature and velocity dis tribution in the melt is very important regarding the safety of the melting process, the process control for producing the required properties of the material or the further development of skull melting installations.The paper describes a new numerical model which is able to simulate the instationary 3D melt flow of glasses and oxides. The numerical model takes into account electromagnetic, convection and Marangoni forces. By this a comprehensive view of the hidden processes in the practical experiments could be. By the new numerical model different glass and oxide melting processes were simulated and the results were compared with experimental results. The comparisons show first of all a very good agreement between experimental and numerical results at the melt surfaces. Additionally the numerical results allow to look much deeper inside the melt and show interesting new effects of the heat and mass transfer below the melt surface which were unknown before.