Electromagnetic Field Under The Action Of Liquid Metal Surface Movement And Control Law

With the continuous development of the theory of hydromagnetics and its application in metallurgy, more and more diversified electromagnetic field are imposing in traditional foundry to improve the quality of casting metal. Among the rest, the electromagnetic shaping (electromagnetic casting and electromagnetic continuous casting) and electromagnetic stirring techniques both are very important applications. The motion of the molten metal surface has great effects on quality of casting metal. As a result, to obtain the controlling rule of electromagnetic field of the motion of molten metal surface, the distributing rule of electromagnetic field imposed in electromagnetic shaping and electromagnetic stirring system and the motion of the molten metal surface under different electromagnetic field were systemic studied in dissertation.The motion of the molten metal surface was measured by a laser gauging sensor and the distribution of electromagnetic field in different experiments was measured by "the small coil method". Main research results are as follows:The distribution of electromagnetic field in inductor goes sameness when imposing high frequency magnetic field and intermediate frequency magnetic field where the magnetic flux density is symmetry along the center of inductor height and in which the distance from the center of inductor is further, the magnetic flux density is stronger. High melt surface stability could be obtained when molten metal level is located equally with upside of induction coil.Not the distribution of electromagnetic field but just the magnitude of the magnetic flux density is changed when modifying power and the magnetic flux density is stronger when power goes greater. The shape of melt surface rises and the fluctuation of melt surface increases when power goes greater. Stronger magnetic flux density could be obtained when imposing intermediate frequency magnetic field and the shape of melt surface rises higher when frequency of magnetic is 2.5kHz than 30kHz.The magnetic flux density in molten metal under condition with loading is almost zero because the phenomena of "skin effect" exists, and the distribution of it is the same as which without loading. The fluctuation rule of melt surface in different radius is almost the same under certain magnetic frequency and power. The magnetic flux density and the stirring intensity are stronger when field frequency is 5Hz than lOHz and the depth of melt surface burble comes bigger when power goes greater.