Numerical Simulation Of Magnetic Field And Flow Field In Electromagnetic Stirring In Ladle Furnace (LF-EMS)

Electromagnetic stirring in ladle furnace (LF-EMS) is an important stirring means of ladle furnace refining process. Electromagnetic stirring (EMS) utilizes the electromagnetic force that intensifies flow of molten steel. The flow improves the conditions of heat transfer and mass transfer and meets the requirement of thermodynamics and dynamics in ladle refining. Combined the other ladle refining means, for example electric arc heating, electromagnetic stirring can bring good metallurgy efficiency. Electromagnetic stirring has highly reliability, safety and economic. It can significantly improve the quality of steel products and production efficiency.The ANSYS is a large popular finite element analytic ware. Based on the electromagnetic theory and flowing theory, the three dimensional finite element model of magnetic field and flow field of molten steel was built by ANSYS. The electromagnetic fields and the liquid metal velocity in the coupling fields were studied by the method of numerical simulation. The simulation results show that, under the coil loading, alternating electromagnetic fields are generated around stirrer, along the ladle radius direction the magnetic field intensity in the liquid steel shows acute attenuation; the electromagnetic force is generally upward direction, thus promotes the molten steel along the ladle wall upward movement, and forms a single large circulation, while, the speed and turbulent kinetic energy distributes evenly. The flow meets the need of ladle metallurgy.In the different of coil winding and current forming of power supplying, the distribution of magnetic field and flow field in ladle furnace is basically the same, different in numerical. For the 90t ladle, electromagnetic stirrer preferentially selects the forms of centralized winding, loading two-phase low-frequency current electromagnetic stirrer.The distribution of magnetic field and flow field in different distance between ladle and stirring were researched. With the decreasing distance between ladle and stirring, induction density and magnetic force in ladle furnace can be further enhanced, so it could play a very good mixing effect. In actual working conditions permitting, it should minimize the distance between ladle and stirring as far as possible. The influence of technological process parameters, including current intensity and current frequency are investigated. The results show that, while the increasing of the current intensity and current frequency, the stirrer can increase the stirring intensity and expand the stirring area,but too much of steel flow velocity makes against the refining of steel. Electing frequency range from 1.1Hz to 1.8Hz, current intensity in a range from 800A to 1200A, process conditions can meet ladle refining requirements.