<p>Any conductor carrying electric current generates a magnetic field, with stronger currents producing more significant magnetic effects. In an electrolysis cell, direct current enters through busbars, whose structure critically affects the magnetic field distribution inside the cell. Conductive fluids exhibit flow fluctuations in the presence of magnetic field. Magnesium electrolysis involves a multiphase flow process where the combined effects of anode chlorine bubble drag force and Lorentz force drive electrolyte circulation, although the exact circulation mechanisms remain unreported. The multipolar cell represents a specialized magnesium electrolysis reactor with extremely narrow interelectrode channels. This study establishes a multiphysical field coupling model of electromagnetic-flow fields for magnesium electrolysis multipolar cells utilizing the finite element method to analyze their magnetic field characteristics and Lorentz force distribution. We primarily investigate magnetic field-induced flow intensification, comparing electrolyte flow with and without Lorentz force effects, including overall circulation patterns and interelectrode channel velocity distributions. The results reveal that while the Lorentz force has a limited overall effect on the electrolyte compared to the dominant gas-liquid phase forces, it can intensify wall flushing in specific areas, which may be mitigated by regulating the magnetic field and current distribution through busbar design. Turbulence intensity within the interelectrode channel primarily ranges between 10 and 20%. This work establishes a Multiphysics model quantifying Lorentz-force-gasflow interactions in industrial-scale multipolar cells, revealing how electromagnetic fields influence electrolyte circulation in narrow interelectrode channels and providing valuable insights for cell design optimization.</p>