CFD simulation of jet behaviors in a binary gas-solid fluidized bed:comparisons with experiments

Based on the experimental observation of the fluidization characteristics of solid mixtures(resin and rapeseed)with different densities and sizes,the jet behaviours of the binary system are simulated in a twodimensional jetting fluidized bed 0.30m in width and 2.00m in height.A simple mathematical model,by introducing two additional force terms in both gas and particle phase momentum equations of Gidaspow’s inviscid two-fluid model,is used to explore the effects of jet gas velocity and mixture combination on the jet penetration depth in the fluidized bed with a binary system.Experimental results show that there is a fluidization velocity interval(u_(if)-u_(ff))for the resin-on-rapeseed(flotsam-on-jetsam)segregated bed.The simulated jet penetration depth increases with the increase of jet gas velocity and the volume fraction of the flotsam(resin),which is in fair agreement with experimental data.The above findings show that the hydrodynamic model of Brandani and Zhang(2006),by introducing the average physical properties from Goossens et al.(1971),can be used to predict the jet behaviors of a well-mixing binary system.

Jet Behavior and Metallurgical Performance of Innovated Double-Parameter Oxygen Lance in BOF

A double-parameter oxygen lance used in a 300 t converter was designed to improve the metallurgical performance. A small-scale measurement of the jet behavior was done using a computer controlled scanning system. The experimental data on the velocity distribution at the jet centerline, the contour map of the jet velocity, the deviation of the jet centerline, and the velocity distribution of the axial section were compiled. According to the results of the small-scale measurement, the double-parameter lance was also employed for a BOF experiment. The metallurgy inde- xes show that the metallurgical performance was highly promoted by use of the double-parameter lance.

Numerical Simulation of Jet Behavior and Impingement Characteristics of Preheating Shrouded Supersonic Jets

As a novel supersonic jet technology,preheating shrouded supersonic jet was developed to deliver oxygen into molten bath efficiently and affordably.However,there has been limited research on the jet behavior and impingement characteristics of preheating shrouded supersonic jets.Computational fluid dynamics（CFD）models were established to investigate the effects of main and shrouding gas temperatures on the characteristics of flow field and impingement of shrouded supersonic jet.The preheating shrouded supersonic jet behavior was simulated and measured by numerical simulation and jet measurement experiment respectively.The influence of preheating shrouded supersonic jet on gas jet penetration and fluid flow in liquid bath was calculated by the CFD model which was validated against water model experiments.The results show that the uptrend of the potential core length of shrouded supersonic jet would be accelerated with increasing the main and shrouding gas temperatures.Also,preheating supersonic jets demonstrated significant advantages in penetrating and stirring the liquid bath.