Mathematical model of supersonic jet centerline velocity for multi-nozzle oxygen lance

Abstract

The supersonic jet characteristics of multi-nozzle oxygen lance are the key to the quality of converter steelmaking. It is of great significance to clarify the velocity distribution characteristics of multi nozzle jet centerline to guide the production practice of converter steelmaking. Taking the oxygen lance for 260 t converter as the object, a three-dimensional geometric model is established to study the distribution characteristics of jet centerline velocity under different Mach number and inclination. The synergistic effect of Mach number and orifice inclination on jet attenuation is mainly studied. The mathematical expressions of jet deflection, Mach number and jet inclination are established, the calculation method of jet centerline deviation is proposed, and the previous mathematical model of jet centerline velocity is improved. The results show that the momentum transfer coefficient Kj of multi-nozzle oxygen lance is not only related to Mach number, but also affected by jet inclination. The deviation between the corrected mathematical model and the field measured results is 4.3%.