Optimizing the Performance of a Dual-Injection Gas-Stirred Ladle Using Physical Modeling

Herein, the effects of the angle between nozzles, oil thickness, gas flow ratio, and gas flow rate on mixing time and open eye area in a physical model of a gas-stirred ladle with dual plugs are studied. The effect of the variables under study is determined using a two-level factorial design. Particle image velocimetry (PIV) is used to establish, through the analysis of flow patterns, the effect of the studied variables on the hydrodynamics of the system. Results suggest that operating conditions significantly change the flow structure and greatly influence the system's mixing time and open eye area behavior. The Pareto front of the optimized results on mixing time and open eye area is obtained through a multiobjective optimization using a genetic algorithm (NSGA-II). The results are conclusive in that, for optimal performance, the ladle must be operated using an angle slightly higher than 90 degrees between plugs, a differentiated flow ratio, high oil thickness, and a gas flow rate adjusted according to whether the preference is given to the protection of the bath or to the mixing process.