A corrective forcing term in the lattice Boltzmann explicit velocity-difference model for mass transfer applications

The lattice Boltzmann method (LBM) is a mesoscopic approach to model transport phenomena, capturing the fluid behavior and integrating thermodynamics. However, LBM often oversimplifies the mass transfer modeling by relying on passive scalar and inconsistent force models. This study focuses on improving a kinetic-based collision model by incorporating a corrective forcing term, identified through Chapman-Enskog analysis, to ensure accurate recovery of the Navier-Stokes equation at low Knudsen number. The impact of the corrective term is validated using the Couette flow benchmark with suction-injection for a fixed Péclet and varying Reynolds numbers. Although numerically negligible, it is crucial for eliminating spurious algebraic terms and enhancing mass transfer modeling in LBM.