| With sixty years progress, continuous casting technology is now developing to the orientation of high withdrawal velocity and near net shape of few-defect products, accompanied by a series of relative technologies concerning tundish, mold and second cooling zone aiming at high efficiency, high quality and diversity products.Having functions of purification, solidification, heat exchange and chemical reaction, continuous casting mold is the important chain of strand quality control and the key part influencing on molten steel flow, heat transfer and solidification.Electromagnetic stirring (EMS) has been widely applied in continuous casting process for its advantages of high energy density, non-contact and easy control. The mechanism that mold EMS improves strand quality is intensive fluid flow and heat/mass transfer of solidification process by means of electromagnetic force. The distribution of magnetic field and electromagnetic force is the foundation of analysis fluid flow and heat transfer. Although some physical experiments and mathematical modeling of EMS have been reported, the researches on theoretic analytic modeling of EMS and the distribution character of electromagnetic field used in continuous casting are still imperfect for its complication. These problems are just the difficult points of EMS investigation and the obstacles of EMS developing.The present subject is part of a research project submitted by Baoshan Iron and Steel Corporation named Study on ManufactureTechnology of Round Billet with High Withdrawal Velocity and Non-Defection. The project demanded to prove up factors that influenced strand quality with mold EMS in round billet continuous casting. With this purpose, electromagnetic stirring was investigated in aspects of theoretic analysis, mathematical modeling, computer simulation, experimental measure and process optimization.During the theoretical analysis of electromagnetic stirring process of continuous casting of round billet, the effect of several elementary dimensionless numbers including Reynolds number (Re), magnetic Reynolds number (Rem), Hartmann number (Ha) and magnetic interaction parameter (N) on electromagnetic stirring procedure were analyzed. The quasi-static magnetic field equations of EMS in continuous casting mold and electromagnetic force equations were deduced at right angle and column coordinate system based on magneto-hydrodynamics equations. According to the physical meaning of dimensionless numbers, the influence of liquid steel flow on electromagnetic field could be neglected during the analysis of EMS process in continuous casting so that its analysis and calculation could be simplified. Moreover, the models of magnetic field and electromagnetic force of arbitrary empty loaded windings were illustrated by mathematical analytic method. Based on above work, the distribution modeling of 2-D and/or 3-D electromagnetic field, electromagnetic force for traveling wave and rotating magnetic field in continuous casting mold were obtained respectively, which provided theoretic foundation for the analysis of EMS process. It shows that the distribution of magnetic field and electromagnetic force are related to current strength, frequency, the pole pair number of thestirrer, spatial position and media parameters.According to general equation of fluid flow and heat transfer, 2-D and/or 3-D mathematical modeling of fluid flow and heat transfer with/without EMS in continuous casting mold were presented at right angle and column coordinate system. The mathematical modeling of electromagnetic field of EMS in continuous casting was described by means of the combination of magnetic vector potential and electric scalar potential. Furthermore, the mathematical modeling of meniscus shape of molten metal in continuous casting mold was deduced and analyzed under conditions of static state and electromagnetic field. Comparing their calculated modeling, the difference is that electromagnetic force changes liquid steel flow consequently to influence meniscus shape with EMS...
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