Abstract: High-speed slab continuous casting can significantly improve production efficiency;however,severe fluctuations in liquid surface flow velocity under high casting speeds are prone to causing slag entrainment defects,and most conventional slab continuous casters are not equipped with electromagnetic braking systems.To explore a lowcost and high-efficiency flow field control method under high casting speeds,this study proposes a new approach:suppressing rapid liquid surface flow by inserting baffle rods.Using a combination of numerical simulation and physical water modeling,a 920 mm×180 mm mold model was established.With the diameter（30,50,70 mm）and insertion depth（10,15 cm）of cylindrical refractory rods as variables,the regulation laws of cylindrical baffle rods on the liquid surface flow velocity and fluctuation in the mold were investigated.The results show that the diameter of the baffle rod plays a dominant role in regulating the mold flow field.Compared with the condition without a baffle rod,the 70 mm baffle rod reduces the overall flow velocity by 19.5%,which is 3.2 times the reduction rate of the30 mm baffle rod（6.1%）.The reduction in liquid surface fluctuation increases from 11%to 39%,a 3.5-fold improvement.The effect of insertion depth on the flow field exhibits a threshold effect:only when the diameter is no less than 50 mm,increasing the insertion depth to 15 cm can additionally reduce the flow velocity by 3.2%-5.4%and the fluctuation by 12.8%.For small-diameter rods（30 mm）,increasing the depth has a weak regulatory effect.The optimal parameter combination in this study is a baffle rod with a diameter of 70 mm and an insertion depth of15 cm.Under this condition,the maximum liquid surface velocity（at point P2）decreases to 0.2m/s（a cumulative reduction of 17.7%）,and the velocity in the central area（at point P4）decreases to 0.115 m/s（a reduction of22.8%）.The fluctuation value in the jet core area（at point P2）decreases to 0.21 cm（a reduction of 40.0%）,and the fluctuation in the slag entrainment risk area（P2/P5）stabilizes at 0.21-0.23 cm.