Influence of Ambient and Oxygen Temperatures on Fluid Flow Characteristics Considering Swirl-type Supersonic Oxygen Jets

摘要

In vanadium extraction converter steelmaking, the swirl-type oxygen lance has been applied to improve the dynamic condition of the molten bath reaction to achieve a higher oxidation rate of vanadium and better vanadium slag quality, because the swirl-type jet can generate not only axial and radial forces but also tangential ones. Recently, the swirl-type supersonic jet with preheated oxygen was proposed to further enhance the agitation ability of the oxygen jet on the molten bath. In this study, the effects of the ambient temperature and oxygen temperature on the swirl-type supersonic jet behavior were analyzed to achieve better formulation and optimization of the process parameters. The flow characteristics of swirl-type oxygen jets were simulated by computational fluid dynamics software at 300 K, and 1 700 K ambient and 300 K, 450 K and 600 K oxygen temperature, and partial results were validated against data from a preheating jet experiment. An analysis of the results shows that the centerline jet velocity was increased by preheated oxygen, and at higher ambient temperature, a longer core length was formed and the velocity fluctuation was aggravated. The influence of the preheating temperature on the core length was more evident at lower ambient temperature. From a dynamic perspective, the molecular motion was improved and with respect to energy, the internal energy of the oxygen jets could be preserved at higher ambient temperature.