Dulce Y. Medina

Influence of the Slag Density on the Splashing Process in a Steelmaking Converter

The way in which slag density influences the slag splashing phenomenon in an oxygen steelmaking converter is numerically analyzed in this work. Several values of the density of the slag are considered, and their effect on the global mass balance and slag average volume fraction on the sidewalls of the converter is studied using isothermal, two-dimensional transient computational fluid dynamics simulations. Diameter of the slag drops is determined from the slag density and the impact velocity of the nitrogen jet. Besides, the effect of the nitrogen jet Mach number on the slag splashing is simulated and discussed. A qualitative comparison between the computer simulations and results from the literature is made.

Computer Analysis of a Methane Fired Crucible Furnace

Two design factors and one operation parameter of a methane fired crucible furnace are numerically explored in this work. These are the number of burners, the location of the exhaust gas exit, and the air-fuel ratio, respectively. Three dimensional steady state Computational Fluid Dynamics simulations are carried out in order to analyze the influence of the above factors on the mean cavity temperature in absence of thermal load, the methane content and the oxygen content of the exit gas.

Advantages of Hot Compression in the Manufacture of Al-B 4 C Composites

The aim of this work was to prove that preparation of Al-B4C by hot compression at 350 °C (HC) followed by sintering at 550 °C would improve mechanical properties with respect to manufacturing by cold compression (CC) followed by sintering at the same temperature, the later experiments were carried out in a previous work. Samples with aluminum matrix adding 0, 3, 5 and 7% were prepared by powder metallurgy technique and tested. The mechanical properties were better using HC. Remarkably, resistance to compression was 3.5 times larger for HC. Vickers hardness, resistance to wearing and impact, as well as density were higher for HC. Scanning electron microscopy of CC specimens exhibit a cellular microstructure while HC ones display a smooth appearance. The better properties of the HC samples are explained due to an improved flow of material at higher temperatures of compression.

Heat Transfer and Solidification of Molten Iron in a Pipe

The effect of the pipe wall temperature on the heat transfer and the internal solidification phenomena during the pouring of pure molten iron in a pipe is studied in this work. A mathematical model consisting in the motion, mass balance and heat equations is proposed. The Reynolds Stress Model is employed to simulate turbulence. The mathematical model considering transient three-dimensional simulations is numerically solved using the Computational Fluid Dynamics technique. To simplify the mushy zone problem, pure iron considered. Numerical simulations show that a pipe wall temperature of 300 K promotes early solidification and blockage, and yields strong internal gradients of velocity and temperature. Besides, a pipe wall temperature of 1000 K prevents solidification and promotes a more homogeneous flow and temperatures contours of molten iron in the pipe.

Numerical Analysis of Multiphase Flow in a Steel Oxygen Converter With Top and Bottom Blowing

Combined blowing in the steelmaking basic oxygen converter is a technique that allows more agitation in the metal bath, and gives a fast decarburization rate, accelerated removal of impurities and chemical and thermal homogenization. In this work the multiphase flow in an industrial-like basic oxygen converter with top and bottom blowing is analyzed by means of Computational Fluid Dynamics software. Turbulence in the converter is simulated by means of the classical K-e model given that this model yields more numerical stability during the integration for long times. Top jet velocities of Mach 1 and Mach 2, and 50 and 100 m s−1 of bottom injection velocities are used, and the results are compared with the conventional top blowing injection. Numerical results show that the combined blowing generates more agitation of the metal bath than that of the top blowing, however, from an operating viewpoint, combined blowing promotes that a significant volume of molten metal be expelled from the converter mouth.Copyright