STUDY OF THE BEHAVIOR OF CURRENT-CARRYING LIQUID IN THE BATH OF DC ARC FURNACE BY AN EXTERNAL VERTICAL MAGNETIC FIELD ON A PHYSICAL MODEL

When an external vertical magnetic field is applied to a current-carrying melt in the bath of a DC arc furnace, volumetric electromagnetic forces arise that drive it. Flows of metal and slag occur in the bath of the DC arc furnace. This can lead to their efficient mixing, but can also carry negative aspects,for example, associated with an increase in wear oflining in the region of the bottom electrode. The processes of conductive mixing in the bath of the DC arc furnace during smelting of metals and alloys remain poorly understood, there arise both theoretical questions related to the nature of the flows in the bath under the action of external and intrinsic magnetic fields of a given intensity, and practical with the absence of simple and reliable sources of external magnetic fields. The purpose of this paper isto qualitatively test the capabilities of a physical "transparent" model, to study the nature of currents of a current-carrying liquid under the action of an external vertical magnetic field, and to analyze the possibility of transferring simulation results to processes occurring in a five-ton bath of an industrial DC arc furnace. The principal possibility of studying the current flow behavior of a current-carrying melt under the influence of external magnetic fields on models using non-metallic electrically conducting transparent liquids is shown. In this work the authors have used a water solution of table salt, it allowed to estimate the velocity of the liquid on itsfree surface and near the bottom electrode using video. The physical modeling of the effect of an external vertical magnetic field on the current flowing current in a bath was carried out for different combinations of connecting the bottom electrode and different currents flowing through the bath. The current flowing current in the bath under the influence of an external vertical magnetic field was established when the central electrode or the bottom electrode is displaced from the axis of the bath. It was revealed that when the axis of the bottom electrode is displaced from the bath axis, the average rotation speed of the liquid in the horizontal plane increases. An estimate of the value of the vertical magnetic field strength (about 5  kA/m) is obtained, which should be accompanied by conductive mixing the metal bath of the five-ton steel-smelting arc furnace.

DC arc furnace, current-carrying melt, bath of a DC arc furnace, bottom electrode, intensity of magnetic field, flow pattern, volumetric electromagnetic forces, velocity melt

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