Modelling on the penetration depth of the coherent supersonic jet in EAF steelmaking

Abstract

The coherent supersonic oxygen supplying technology is now widely adopted in EAF steelmaking process. However, there has been limited research on the impact characteristics of the coherent supersonic jet. In this work, integrating theoretical modelling and numerical simulations, a hybrid computing model was developed to predict the penetration depth of the coherent and conventional supersonic jet. The results show that the lance height has much significant influence on the jet penetration depth, and the penetration depth of the coherent supersonic jet is much larger than that of the conventional supersonic jet at the same lance height. The k value reflects the velocity attenuation of the main supersonic jet, which is a key parameter of the hybrid computing model. Finally, the hybrid computing model and its modified models can well predict the penetration depth of the coherent and conventional supersonic jet with the error being no more than 3.92 pct.

Effect of Lance Structure on Behavior of Coherent Jet in EAF Steelmaking Process

“…The pitot tube was designed with a water-cooled structure. When the dynamic and static pressure were measured by the pitot tube, the Equations (1) and (2) were used to calculate the axial velocity of the coherent jet [18] (…”

“…The oxygen lance plays an important role in the electric arc furnace (EAF) and basic oxygen furnace (BOF) steelmaking processes, which delivers the oxygen into the molten bath under supersonic condition [1,2]. Before the supersonic jet reaches the molten bath, its velocity keeps reducing, because of an entrainment phenomenon between the jet and the surrounding ambient gas, which lowers its impaction ability and oxidation rate [3,4].…”

Investigation on Coherent Jet Potential Core Length in an Electric Arc Furnace

“…However, the computational expenses will limit the use of the model for industrial applications. Alam et al use a one‐step CH 4 ‐O 2 combustion reaction, while Wei et al use GRI‐Mech 3.0 for CH 4 ‐O 2 combustion reactions.…”

“…[4] The eddy dissipation (ED) combustion model with simplified one-step methane-oxygen reaction mechanism was applied to simulate the combustion process. Validation of the CFD model was conducted by comparing the jet axial velocity with the measurements obtained by Anderson et al [2] Wei et al [5,6] also studied the coherent jet with CO 2 and O 2 mixed injection simulation. The eddy dissipation concept combustion model was applied and used GRI-Mech 3.0 mechanisms to calculate the methane-oxygen combustion.…”

“…Alam et al use model modifications for conventional supersonic jet and coherent jet. However, Wei et al either use the standard k‐epsilon turbulence model or change the model constant. Selection of combustion model reaction mechanism is another critical factor that will affect the prediction of jet flow properties.…”