Numerical Studies on Molten Steel Flow and Heat Transfer in a Thin-slab Steel Caster under Different SEN Designs
(Room 202A)
09 May 17
10:30 AM
-
11:00 AM
Tracks:
Industrial Laser Welding, Surface Treatments & Gas Interaction During Casting of AHSS
Occurrence of break-outs (BO) during casting of narrow slabs has been observed to be influenced by the SEN design in one of ArcelorMittal’s thin-slab casters. 3-D computational fluid dynamics (CFD) models are developed to perform both steady-state and transient simulations of molten steel flow and heat transfer in the SEN and in the CSP caster for three four-port SEN designs (type- A, B and C designs). Despite of the similar port size and location among all three SENs under study, two major design differences exist, including a top insert design at SEN entrance and height of the flow divider at the bottom of the SEN. The computational models are validated by water model measurements of SEN port opening velocities. Both water model experiments and numerical simulation results suggest that SEN design with a taller bottom flow divider causes the increase of both mean and variations of the upper port flow rates and the left-right biased flows in the SEN with, which leads to large-scale asymmetric flows in the CSP mold region. Transient heat transfer simulations further show that this unstable biased flow in the mold increases the occurrence of “hot spots” near the shell around the funnel-to-flat transition region, which might be responsible for local steel re-melting and break-out as ferro-static