Reflection of simple wave at vapor-liquid interface accompanied with phase change

When a sound in a vapor is reflected at an interface between the vapor and its condensed phase, the reflected wave is affected by a reflection-induced phase change at the interface, for which the macroscopic continuum theory cannot be applied and the boundary-value problem of the Boltzmann equation should be solved. We numerically solve the Boltzmann-Krook-Welander equation with a finite-difference method, and clarify the characteristics of the reflected wave and the reflection-indeced phase change.When a sound in a vapor is reflected at an interface between the vapor and its condensed phase, the reflected wave is affected by a reflection-induced phase change at the interface, for which the macroscopic continuum theory cannot be applied and the boundary-value problem of the Boltzmann equation should be solved. We numerically solve the Boltzmann-Krook-Welander equation with a finite-difference method, and clarify the characteristics of the reflected wave and the reflection-indeced phase change.