CFD modelling of shrouded jet impingement on a liquid surface

A computational fluid dynamics (CFD) model was developed to simulate the liquid flow field and surface deformation caused by an impinging shrouded supersonic jet on a liquid bath from the top as used in oxygen steelmaking. Air and water was used to simulate the gas and liquid phases respectively, inside the steelmaking furnace. No slag condition was assumed. Two different computational domains were used to avoid the difficulties that arise from the simultaneous solution of compressible gas phase and incompressible liquid phase. The two computational domains were: 1) single phase domain and 2) multiphase-domain. In the single phase domain, the compressible gas phase was solved and the gas-liquid interaction was simulated in the multiphase domain. The effect of shrouding gas flow rates on the axial jet velocity distribution, depth of penetration and velocity distribution of liquid phase were investigated. A high shrouding gas flow rate was found to increase the potential core length of the jet, depth of penetration and liquid free surface velocity which in turn contributes in reducing the mixing time.