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In steel continuous casting,double-ruler electromagnetic braking(EMBr)is often applied to control the flow pattern in the mold.In addition,argon gas is usually injected to prevent clogging,but the bubbles also affect the flow pattern,and may become entrapped to form defects in the final product.To investigate the combined behaviors,plant measurements were conducted and a computational model was applied to simulate turbulent flow of the molten steel and the transport and capture of argon gas bubbles into the solidifying shell in a continuous slab caster,including EMBr.An Eulerian k-ε model of the steel flow was two-way coupled with a Lagrangian model of the large bubbles using a Discrete Random Walk method to simulate their turbulent dispersion.The top surface velocities agreed well with nailboard measurements,and indicated strong cross flow caused by biased flow of Argas due to the slide-gate orientation.Then,the trajectories and capture of over two million bubbles(25 μm to 5 mm diameter range)were simulated using an advanced capture criterion.The number,locations,and sizes of captured bubbles agreed well with measurements,especially for larger bubbles.The relative capture fraction of 0.3%was close to the measured 0.2%for 1mm bubbles,and occurred mainly near the top surface.About 85%of smaller bubbles were captured,mostly deeper down in the caster.EMBr produced similar behavior with slightly lower capture rates.