The flow field of in a 40 t tundish with different flow control devices for eight-strand continuous casting has been simulated by test of water model with 1-3.5 geometric similarity scale. Results show that the average stagnation time of original tundish is short and the difference of residence time between four outlets at one side of tundish is large ； as compared original tundish the dead area volume fraction of tundish with optimum weir and double diversion holes and with optimum C12W1 rectangle weir respectively decreases by 19. 15% and 31. 49%

and the difference value of stagnation time between four outlets at one side also decreases ； the installed turbulence modifier can increase stagnation time and peak time of molten steel

but not effectively reduce the dead area volume fraction.