Numerical Study of Condensation of a Polyatomic Vapor by a Shock Wave Based on the Kinetic Theory of Gases

A semi-infinite expanse of a polyatomic vapor bounded by its condensed phase is considered. The condensed phase is a thin liquid film on a solid wall of finite thickness. An incident shock wave is reflected at the liquid film, and thereby the pressure behind the reflected shock exceeds the saturated pressure. Then, the vapor begins to condense onto the surface of the liquid film. We present the results of numerical study of the behavior of vapor and the growth rate of liquid film based on the kinetic theory, the Gaussian-BGK model of the Boltzmann equation with a kinetic boundary condition of a mixed type including the condensation coefficient. It is shown that both the behavior of vapor and the growth rate of liquid film are considerably affected by values of the condensation coefficient. The numerical results are also compared with those by a previous theory.