Abstract: Transformation of automatic steel-making was carried out at a steel plant in northern China. In this process, lost of problems had emerged such as low intensity of oxygen blowing , long smelting period, much splashing of molten metal and short lifespan of lance head. According to the fact above, the parameter and operation of oxygen lance have been designed and optimized again and the interaction between the oxygen lance jet and the molten pool has been analogously simulated by Fluent fluid dynamics software. The result shows with the increase of the Mach number of oxygen lance from 1.9 to 2.15 and the change of lance and flow through the L/L0 control, the oxygen lance jet with high Mach number can perform fully and problems mentioned above have been significantly improved as expected.

Key words: high Mach number oxygen gun head, Mach number, numerical simulation, jaw diameter