Distribuição De Gás Inerte Dentro Do Sistema De Refratário Durante O Lingotamento Contínuo De Placas: Modelo Físico E Matemático

Abstract

Distribuição de gás inerte dentro do sistema de refratário durante o lingotamento contínuo de placas [manuscrito] : modelo físico e matemático / Paulo Luiz Santos Junior. -2012.xvii, 83 f. : il. color.; grafs.; tabs.

The Effect of Upper Nozzle Refractory in Bubble Behavior Inside the SEN and Slab Mold in Continuous Casting: Physical and Mathematical Model

“…This in turn demonstrates that the diameter of the bubble in the mold, and the mechanisms that determine this size, rupture and coalescence of the bubbles, is critical in determining the behavior of the continuous phase and dispersed in the mold. This phenomenon was confirmed in a physical model and also been discussed by Banderas et al [13], and Santos et al [9]. Thus the liquid flow rate, for the flow ranges evaluated in this study, influences the process of gas distribution in the mold, besides the direct change of velocity and kinetic energy of the jet at the exit of the nozzle, and also affect the diameter of the bubble in the mold, i.e., higher liquid flows lead to smaller bubble diameters in the mold.…”

“…A modification of the central and upper flow was observed at 400l/min, which in turn allowed the formation of a double roll with smaller velocities in the mold and meniscus than in the 336l/min condition. These behaviors were observed in a physical model and discussed by Santos et al [9] and Banderas et al [13]. When comparing the images of Figure 8 of 336 l / min with those of 400 l / min it is seen that the region of the volumetric fraction is much more expanded in the second case.…”

“…The mathematical model of continuous casting with the MUSIG function showed continuous (water), dispersed (gas) and medium size bubbles compatible with those observed by Santos et all. [9] and Banderas et all. [13].…”

“…The results of the mathematical model of continuous casting nozzle -mold system are shown in figures 7, 8 and 9 for the conditions of 336 l/min and 400 l/min water flow with injection of 12 l / min of air in the upper nozzle. These parameters represent the usual production conditions for ultra low carbon steel (Santos et al [9]). In the mathematical model a minimum bubble diameter of 0.6 mm and a maximum of 3.2 mm for MUSIG function have been used.…”

“…The mathematical model of continuous casting was elaborated in such a way as to represent the physical conditions of the model in water with respect to the actual dimensions of the model. The water flow used was 336L / min and 400L / min with the air flow rate of 12 STPl / min (Santos et al [9]). The mesh was constructed with 350,400 nodes, being more refined at the outlet of the submerged nozzle and in the jet region (Figure 2 b).…”