Numerical Simulation of Water Electrolyzer

Based on the COMSOL Multiphysics platform, a two-dimensional steady-state and transient model of an alkaline (ALK) electrolyzer was established. The model comprehensively integrates thermodynamics, electrode reaction kinetics, ohmic overpotential, two-phase mass transfer, and transmembrane gas diffusion. Dimensional corrections were applied to multiple empirical formulas, while engineering parameters such as electrolyte flow velocity and membrane pore size were introduced to assess their impact on gas purity.Additionally, isotope separation models for dry cathode anion-exchange membrane (AEM) and proton-exchange membrane (PEM) electrolyzers were developed. Key parameters—including the liquid feed/consumption ratio (λ) and kinetic isotope effect coefficient (KIE)—were analyzed to evaluate their influence on outlet deuterium abundance.