Bondar O. Liquid metal electromagnetic stirring systems with periodic action of pulsing and traveling magnetic fields.

The оbject of research: liquid metal electromagnetic stirring systems in melting units and their power supply systems. The purpose of research: increasing of liquid metal electromagnetic stirring systems efficiency in melting units by means of changing force action on it of pulsing and traveling magnetic fields. Methods of research: based on fundamental electromagnetic fields and electric circuits theories positions, electric machines and apparatus theory, methods of mathematical modelling. Theoretical and practical results and innovations: Optimal design solutions of versatile electromagnetic systems based on line inductors with two- and three-dimensional ferromagnetic cores, which create by means of alternate single phase and multiphase power supply respectively pulsing and traveling magnetic fields have been developed, that allows to implement periodic changing of vortex flow structure in furnace bath and due to this to increase the effectiveness of liquid meatal stirring. New principle of liquid metal stirring by means of changing force action on it of pulsing and traveling magnetic fields, created by versatile electromagnetic systems, have been proposed, that allows essentially increase the effectiveness of liquid metal electromagnetic stirring process. For the first time on the basis of multiphysical modelling of interconnected electromagnetic, hydrodynamic and heat processes in versatile electromagnetic systems main regularities of liquid metal electromagnetic stirring in melting units under the alternate action on it of pulsing and traveling magnetic fields have been obtained. For the first time have been detected: a reverse of single circuit vortex flow of liquid metal in furnace bath when changing the magnitude of the pole division of versatile inductor in multiphase power supply mode; reverse of double circuit vortex flow of liquid metal in furnace bath when changing power supply frequency of versatile three-core inductor in single phase power supply mode. For the first time the influence of structural parameters of melting unit (ferromagnetic furnace frame and metal pocket) on effectiveness of versatile electromagnetic stirring system have been determined. A subject degree of introduction: Technical recommendations have been developed and suggestions for creation of versatile liquid metal stirring system and it power supply system have been formulated, which have been transferred to physical and technological institute of metals and alloys of NAS of Ukraine for developing of prototype of versatile electromagnetic stirrer of aluminum melting reverberatory furnaces. Obtained results of multiphysical modelling of physical processes have been transferred to Scientific and production center “Titan” of the Institute of electric welding named after Ye. O. Paton of NAS of Ukraine for using in technology of production of alloy ingots based on titanium and other metals by means of electron beam melting method. Effectiveness of implantation: Significant technical and economic effect have been obtained, that leads to improvement of melt quality, as well as to accelerating dissolution of solid additives, removing harmful impurities. Sphere of use: melting and preparation of metal melts technologies.