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Despite the age of the process, the blast furnace remains critical to industrial ironmaking. With advances in analysis technologies and control systems, and economic pressure from competitive new ironmaking techniques, modern blast furnace operation has become more efficient. However, room still exists for improvement, particularly in the blast furnace raceway region. Further development requires better understanding of phenomena within the blast furnace, including heat transfer, mass transfer, chemical reactions, and multiphase flow. To that end, computational simulation and visualization, in multiple approaches, are increasingly used to explore blast furnace phenomena. Current computational approaches range from simplified tools designed for rapid turn‐around times to complex solvers intended to capture the movement of discrete particles within the furnace. This paper reviews recent current state‐of‐the‐art techniques for simulation and visualization of the blast furnace developed by the Center for Innovation through Visualization and Simulation (CIVS) at Purdue University Northwest (PNW), as well as an overview of other advanced techniques in the field.

Numerical simulations of the coal gasification process inside a generic 2-stage entrained-flow gasifier fed with Indonesian coal at approximately 2000 metric tone/day are carried out. The 3-D Navier-Stokes equations and eight species transport equations are solved with three heterogeneous global reactions, three homogeneous reactions, and two-step thermal cracking equation of volatiles. The Chemical Percolation Devolatilization (CPD) model is used for the devolatilization process. Finite rates are used for the heterogeneous solid-to-gas reactions. Both finite rate and eddy-breakup combustion models are calculated for each homogeneous gas-to-gas reaction, and the smaller of the two rates is used. The water-shift reaction rate is adjusted to match available syngas composition from existing operational data without catalyst. This study is conducted to investigate the effects of different operation parameters on the gasification process including coal mixture (dry vs. slurry), oxidant (oxygen-blown vs. air-blown), and different coal distribution between two stages. In the two-stage coal-slurry feed operation, the dominant reactions are intense char combustion in the first stage and enhanced gasification reactions in the second stage. The gas temperature in the first stage for the dry-fed case is about 800 K higher than the slurry-fed case. This calls for attention of additional refractory maintenance in the dry-fed case. One-stage operation yields higher H 2, CO and CH 4 combined than if a two-stage operation is used, but with a lower syngas heating value. High heating value (HHV) of syngas for the one-stage operation is 7.68 MJ/kg, compared to 8.24 MJ/kg for two-stage operation with 72%-25% fuel distribution and 9.03 MJ/kg for two-stage operation with 50%-50% fuel distribution. Carbon conversion efficiency of the air-blown case is 77.3%, which is much lower than that of the oxygen-blown case (99.4%). The syngas heating value for the air-blown case is 4.40 MJ/kg, which is almost half of the heating value of the oxygen-blown case (8.24 MJ/kg).

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Arc melting is one of the commonly-used melting methods in modern material manufacturing. The present study established a numerical model coupling the electric arc plasma, solid melting, and liquid flow together to simulate the steel ingot melting process using the electric arc. The direct current electric arc behavioral characteristics with varying arc length generated by the moving electrode were analyzed based on the validated model. The effects of both the initial arc length and the dynamic electrode movement on the steel ingot melting efficiency were studied. A potential method was also proposed to apply the established model in simulating the electric arc furnace scrap melting. The study reveals that a reasonable and stable arc length can provide higher instantaneous heat flux and current density and reduce the arc dissipation, meanwhile balance the electrode consumption rate and melting efficiency to achieve the highest economic benefit. In addition, the dynamic electrode movement during the melting process maintains the original arc performance near the ingot top surface, which also results in a positive impact on the melting efficiency.

Gas‐stirred ladles are widely used in the steel secondary refining process. In order to produce high‐quality steel, a range of stirring conditions, from hard stirring for mixing to gentle stirring for inclusion removal, is required. In this paper, a full scale unsteady three‐dimensional computational fluid dynamics (CFD) model is developed to simulate the bubble behavior in a steel ladle. A volume of fluid (VOF)‐Lagrangian approach is applied to simulate multiphase flow characteristics. The VOF method is used to track the liquid steel and slag, while the Lagrangian method is used to track the movement of argon bubbles. A water model is used to validate the gas‐stirred ladle model against experimental data. Flow field and bubble breakup and coalescence phenomena inside the ladle is studied in the baseline case, and the effects of initial bubble diameter and gas flow rate during the stirring process have been investigated through parametric study as well.

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