On the vorticity transfer by electrically induced vorticall flow in two-layer fluid

V. Kh. Vlasiuk¹ - E. Shcherbinin²

¹ Vinnitsa Polytechnical Institute, Vinnitsa, Ukraine
² Institute of Physics, University of Latvia, Salaspils-1, LV-2169, Latvia

Abstract
At the calculating of hydrodynamics in the working region of the electroslag remelting metallurgical process one should take into consideration the presence of two liquid layers, which differ after their physical parameters (electrical conductivity, density and viscosity): upper layer of the melt of slag and lower liquid metal layer, which are separated by moving dividing boundary. Usually the working region has a cylindrical vessel from the upper part of which the electrode being remelted is introduced, the cross-section of which is smaller, but in some cases much smaller, than cross-section of the vessel. As a result of this the formation of electrical vortex flow (EVF) takes place, which arises due of to non-uniform distribution of electrical current density along the height of the slag bath. The general pattern of the EVF can be predicted: it is a jet like flow starting from the smaller electrode and diverging along the radius at the separating boundary and a back flow along the side walls of the cylindrical vessel. At the high intensity of EVF (at high values of melting current) above mentioned types of flow are accompanied by formation of different kind of boundary layers, the interaction between which defines more fine structure of flow in both liquid layers. EVT takes place in a closed cylindrical volume, which has demanded for the introduc-tion of a new concept of the boundary layer and determination of its dimensions at these conditions. Earlier authors proposed for such a specific flows to use the position of the lines with zero vorticity of velocity for the determination of boundaries of the boundary layer. In present work the results of numerical calculations of EVF in two layer cylindrical vessel have been reported, and basing on the study of the distribution of vorticity field the trends in the redistribution of velocity field have been evaluated depending on the parameters of technological process and relative depth of the melt layers. Figs 6, Refs 8.