Vortex formation in the continuous slab casting mould is a troublesome phenomenon that can pull mould powder/slag deep down into the liquid core and potentially damage the product quality. Submerged entry nozzle (SEN) clogging is one of the prime causes of vortex formation. This work is designed to investigate and quantify the inter-related effects of nozzle clogging, casting speed (CS) and SEN submergence depth on vortex frequency and penetration depth through water-model experiments. It is observed that the increase in degree of clogging and CS has an inter-related effect on flow asymmetry and impacted the vortex characteristics. At the combination of highest values of degree of clogging and CS, vortices formed are found to have high values of top-diameter, rotational speed, penetration depth, frequency and life. On the contrary, the SEN submergence depth has showed limited effect on these aspects except the penetration depth. With the increase in SEN submergence depth values, it is found that the number of vortices having depth greater than 80 mm is increased.
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