Modelling of heat transfer coupled with columnar dendritic growth in continuous casting of steel

The general aim of this work is to calculate the extent of the equiaxed zon e in continuously cast steel products Free equiaxed grains can grow only in undercooled liquid regions. Undercooling of the bulk liquid occurs because the columnar dendrite tips growing from the mould reject solutes in the li quid The specific aim of this contribution is to calculate the thermal and physical state of continuously cast steel long products assuming a columnar solidification mode, taking into account the tip undercooling at the solid ification front. A 2-D heat transfer model has been developed where the col umnar solidification mode is assumed. The calculation of the undercooling a t the advancing solidification front is coupled with the heat transfer equa tion. The comparison between the results of the present model and the class ical heat transfer model indicates the importance of modelling the undercoo ling phenomenon. The influence of the secondary cooling has also been studi ed.