Numerical Simulation Of Roll Type Electromagnetic Stirring For Continuous Casting Slab

The Roll Type Electromagnetic Stirring in the secondary cooling zone of the continuouscasting Slab was researched in this article. By means of finite element analysis softwareANSYS, the effects of different process parameters (current intensity and current frequency)and structures of a group of electromagnetic stirrer （the material and the placket angle of thering shielding magnetism）on magnetic flux density and magnetic force in the slab werestudied firstly. Then, the best of process parameters and structures from a practical view weresought in order to make the stirring effect of the Roll Type Electromagnetic Stirring optimize.Lastly the influence of the different roller distances (1220mm、720mm and0mm) and stirringmodes (three-ringlike type and ambi-butterfly type) on the fluid flow of the slab was analyzedon the condition of the best process parameters of the two groups of electromagnetic stirrer.When the current frequency was6Hz and the current intensity ranged from280A to480A,the magnetic flux density and magnetic force were increased as the current intensity but theincreasing extent of the magnetic flux density was becoming smaller. At the current intensity480A the magnetic flux density and magnetic force could reach0.0703T and12692N/m~3.When the current intensity was400A and the current frequency ranged from4Hz to6Hz,magnetic flux density was decreased as the increase of the current frequency but the magneticforce was opposite. The magnetic force could reach maximum value of12736N/m~3.The ring shielding magnetism which was respectively made of copper, aluminum andsilicon steel and the placket angle of which was respectively90degree,120degree,150degreeand180degree was analyzed. Compared with absence of ring shielding magnetism, themagnetic force in the centre of slab obviously decreased when the ring shielding magnetismwas made of silicon steel, but increased by677N/m~3and472N/m~3respectively when the ringshielding magnetism was made of copper and aluminum. When the placket angle of the ringshielding magnetism was180degree, the magnetic force in the centre of the slab was minimal,about1510N/m~3. The maximal value was about11756N/m~3as the placket angle of the ringshielding magnetism was120degree.When the distance of two groups of electromagnetic stirrer was1220mm, four lessstrength circulations were formed for ambi-butterfly type but a strong centre circulation wasformed for three-ringlike type. So in this case the three-ringlike type was better than the ambi-butterfly type. When the distance of two groups of electromagnetic stirrer was0mm, one smallstirring region was formed in the centre of the slab for three-ringlike and the stirring intensity became evidently weakened, but for ambi-butterfly type the ambi-butterfly flow field becamethe very strong single-butterfly flow field. In this case, the ambi-butterfly type was better thanthe three-ringlike type.