A Lattice Boltzmann scheme for electrolytes by an extended Maxwell-Stefan approach

This paper presents an extended multicomponent Lattice Boltzmann model for the simulation of electrolytes. It is derived by means of a finite discrete velocity model and its discretization. The model recovers momentum and mass transport according to the incompressible Navier-Stokes equation and Maxwell-Stefan formulation respectively. It includes external driving forces (e.g. electric field) on diffusive and viscous scales, concentration dependent Maxwell-Stefan diffusivities and thermodynamic factors. The latter take into account non-ideal diffusion behavior, which is essential as electrolytes involve charged species and therefore non-ideal long and short range interactions among the molecules of the species. Furthermore, we couple our scheme to a Finite Element Method to include electrostatic interactions on the macroscopic level. Numerical experiments show the validity of the presented model.