Abstract: By Fluent 6.3, this paper develops a mathematical model of three-dimensional and
three-phase flow in the molten bath of EAF with side accessorial oxygen lance to study the
transient phenomena of jet impingement on molten steel. The simulation result shows that the
impingement of the supersonic oxygen jet will cause impact dent on the molten steel surface, will
inspire wave of the molten bath surface from the dent centre to the bath center, and will cause
vortexes under bath which become the centre of molten steel circumfluence. The velocity of
flowing molten steel under the oxygen lance or around furnace wall will be faster than that at the
center of bath. With oxygen jet enhance, the center of vortexes will be more apart from the
impingement point of jet and will be lower to the bottom of bath. The area of impact dent S (m2) is
almost in linear relationship with flow rate of jet QO2 (m3/h), in direct proportion. After
consulting, the relationship between the area of impact dent and flow rate of jet can be expressed
by the following mathematical equation:
2 0.0004 * 0.0932 .

Key words: electric arc furnace, oxygen jet, three-phase flow, numerical simulation