Numerical Simulation Of Flow And Heat Transfer Characteristics In Electromagnetic Stirring Ladle

LF secondary refining process has efficient refining capabilities to meet user's requirements for high quality products,which has become a key link in steel smelting process.Ladle stirring technology is a significant method to accelerate the smelting reaction rate,improve temperature uniformity and slightly adjust components.It plays a vital role to product high purity steel.In this thesis,the commercial software ANSYS is used to establish a three-dimensional finite element model to simulate the multiphase flow in bottom blowing ladle with electromagnetic stirring for 150t LF ladle.The basic characteristics of the magnetic field,the circulation flow,temperature and concentration distributions of molten steel has studied.It mainly considers the effect of some factors such as stirrer position,current frequency,current intensity on the changes of the multiphase flow,temperature changes and alloy concentration changes in the ladle.The electromagnetic field results show that the level electromagnetic force spinning clockwise,vertical electromagnetic force sticking straight up,the resultant force bring the liquid steel an upward rotational movement.The Euler-Lagrange multiphase flow model is used in the model.When coupled the electromagnetic force to the two-phase flow model,the calculation results show that the liquid steel and argon bubbles rotated in the ladle,argon column shifted and gas-liquid two-phase region extended.So rotational flow can improve the flow rate,short the mixing time,increase the residence time of argon in the ladle and reduce the impact for argon column to slag layer.The center EMS is better than eccentric EMS.Stirring method has little effect to steel temperature drop rate.After applying EMS in ladle bottom,the alloy added location need to be adjusted to the exit of argon,where the alloy diffused rapidly and mixing time is shortened.For center EMS,the greater the current intensity is,it will strength liquid rotational motion,increase liquid temperature,short alloy mixing time.Current frequency of the ladle has little influence on the flow field,temperature and concentration field.