Physical and mathematical models of steel flow and heat transfer in a tundish heated by plasma

Temperature control of liquid steel by plasma heating is physically and mat hematically modeled. A dimensionless plasma heating number is employed for scaling up of healing operations between a steam jet for water model and a plasma prototype. Overall responses of step-input temperatures in steel are fairly well predicted by the physical model. Fluid-flow structure and ther mal fields, in terms of dimensionless temperatures, of steel are different from those of water. Two positions of plasma in a tundish were studied, cen tered and off-centered. The second position decreased the heating response of a plasma, although a more homogeneous thermal field was obtained in rega rd to the first position. Consequently, a centered position offered a faste r thermal response than the off-centered one. Flow controllers decreased th e efficiency of plasma due to the formation of stagnant zones located in th eir proximity, which were not active enough to exchange momentum and heat w ith the bulk flow.