Abstract: Based on the prototype of a tundish for fourstrands symmetrical casting 360 mm×480 mm bloom, the effect of different flow control devices on flow field of liquid in tundish were studied by using geometric similarity raito 1∶3 water model to get optimum baffle. Results show that average residence time in tundish without flow control device is rather small, and dead area volume fraction was 50.09 %; with using the optimum new Ytype baffle, piston flow zone in tundish increased by 14.22 % and dead area volume fraction decreased by 32.49 %, the standard deviation of average residence time of two nozzle is small. Onsiteexperiment shows that T.O mass fraction in liquid in tundish is decreased by 45.61 % and total inclusions are reduced from 0.46 mg/kg to 0.17 mg/kg.

Key words: tundish of four strand casting, numerical simulation, physical simulation, flow field