Thermal Lattice Boltzmann Bgk Model for Ideal Binary Mixtures

A lattice Boltzmann model for binary mixtures is formally derived from a two-fluid kinetic model for Maxwell molecules by discretizing the Boltzmann equation. In this model, collisions among the same and different species are treated separately, as non-linear BGK terms, enabling the independent management of the species viscosities and thermal conductivities from the binary diffusion coefficient. The velocity space is discretized in accordance with a quadrature method with prescribed abscissas. A Chapman-Enskog analysis is performed for deriving the macroscopic mass, momentum end energy transport equations. The model is verified against the analytical solutions of the diffusion equation for several concentration, velocity and temperature initial conditions.