Dyanmics of unsteady one-phase turbulent flows in a continuous casting mould

The fluid flow dynamics of one-phase flows of liquid steel in a continuous casting mould was physically modelled using digital particle image velocimetry technology and mathematically simulated using a large eddy simulation approach. Both analyses showed that the flow of liquid through the mould fluctuates with time yielding asymmetrical and biased flows through both submerged entry nozzle (SEN) ports. Reynolds stresses close to the SEN ports increase approximately tenfold when the casting speed is increased from 0.8 m/min to 1.8 m/min. The highest Reynolds stresses are located in the boundary between the entering jet and the liquid bulk inside the mould producing high shear rates, Vorticity maps observe a random behaviour over time of magnitude and sign in the flow field at low casting speeds (0.8 m/min) and a layered structure with a more regular behaviour at high casting speeds (1.2 and 1.8 m/min). Vorticity and velocity/vector maps should be useful for SEN design aimed at higher casting speeds than the conventional ones with good control of fluid flow turbulence.