Computational Simulation of Electromagnetic Fields in an Aluminum Electrolysis Cell

Computational assessment of magnetohydrodynamic stability in aluminum electrolysis cells is predicated on the availability of electromagnetic data of sufficient fidelity. While the currents within the fluid layers may be resolved considering only conductors local to the cell of interest, the other Lorentz interaction driver, the magnetic field, may be realizably influenced by conductors and magnetizable materials near and far. Quantification of acceptable domain extent is subject to the specifics of the operation. Furthermore, simulations must remain tractable in economically viable timeframes to be of engineering use, placing additional constraints on the extent of the modeled domain. This study seeks to elucidate the subjects of extent and fidelity concerning the cell technology at Alcoa’s Mosjøen smelter. Toward that goal, this effort explores the formulation and execution of electromagnetic simulation using the commercially available COMSOL Multiphysics. Domain truncation, as well as conductor and ferromagnetic component fidelity of neighboring cells, are investigated.