Abstract: To improve the mixing effect and inclusion removing during the ladle bottom blowing refining process at an electric furnace factory,the water modeling experiment was conducted. Results show that the distance of two gas columns is too close,so stacking and shifting of the gas columns occur when the gas flow rate is large,which make the flow field of molten steel unstable. According to the results,it is proposed that the bottom blowing position should be located at 0.5R-0.5R-135°(R is the ladle bottom radius),and the critical gas flow rate for slag entrapment is 0.24 m³·h^-1.