contact discontinuities. In order to reduce these difficulties, many methods have been attempted, such as modifying This paper concerns the extension of the gas-kinetic BGK-type scheme to multicomponent flow calculations. In this new scheme, the flux function [13], introducing nonconservative varieach component satisfies its individual gas-kinetic BGK equation ables [11], or designing the specific numerical discretization and the equilibrium states for each component are coupled in space to update Y for certain flow solvers [1]. Currently, hybrid and time to have common temperature and velocity. The particle schemes have become popular for multicomponent flow diffusion in gas mixtures is included naturally in the gas-kinetic calculations [12]. Based on gas-kinetic theory, many lattice model. The current scheme can handle strong shocks and be oscillation-free through the material interface. The scheme guarantees of the material interface ( ฯญ 0). The numerical results confirm the collisionless Boltzmann equation, yielding results which accuracy and robustness of the BGK-type scheme. แฎ 1997 Academic are more diffusive than those obtained from classical high Press resolution difference schemes. The physical reason and remedy for this is analyzed in a recent work [22]. 122