Numerical modeling of solidification front shape in electroslag remelted ingot under correction of electrode metal drop trajectory

The present study addresses numerical modeling of the solidification front dynamics in an electroslag remelted (ESR) ingot, achieved through targeted adjustment of the trajectory of molten electrode metal drops falling into the slag bath. Particular emphasis is placed on analyzing the effect of forced rotation of the consumable electrode on the spatial distribution of temperature fields and morphology of the solidification boundary. Numerical experiments were conducted for an industrial-scale ESR unit equipped with a water-cooled copper crystallizer (90 mm in diameter) and a consumable electrode (40 mm in diameter). Development of a digital twin based on computational fluid dynamics and magnetohydrodistics principles enabled accurate reproduction of the actual production process and identification of heat and mass transfer patterns. Analysis of temperature gradients allowed precise localization of zones with maximum heat generation. Visualization of numerical fields near the steel solidus temperature confirmed the radial shift of the drop trajectory toward the periphery of the slag bath within the range of 25 – 35 mm. The mathematical model consistently integrates Maxwell’s equations for electromagnetic field calculation, conservation laws of mass and momentum, and thermal kinetics accounting for Joule heating. Numerical calculations under direct current polarity demonstrated that centrifugal displacement of drop transfer, combined with reversal of convective flows, promotes formation of a stable horizontal solidification front. This modification substantially enhances structural homogeneity of the ingot and minimizes the thickness of transition zones between layers in multilayer castings. A critical range of electrode rotation speeds was established; exceeding this threshold destabilizes the meniscus, enlarges drops, and deteriorates product quality. The obtained theoretical results fully correlate with full-scale experimental data. The model was verified by comparing calculated and experimental data on position of the interfacial boundary. The scientific substantiation of implementing controlled electrode rotation for optimizing thermal process parameters, ensuring stable metal quality, and improving overall energy efficiency of metallurgical production is provided.

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