Evaporation and condensation phenomena of a binary gas mixture on a droplet

Abstract

The aim of the present project is to model numerically the steady evaporation and condensation phenomena which take place on the surface of a spherical droplet suspended in a binary mixture composed by its vapor and a non-condensable gas at arbitrary Knudsen number. The numerical modeling will be focused on the solution of a kinetic model to the Boltzmann equation with appropriate boundary conditions. The rigid-spheres model to the intermolecular interaction potential will be assumed. The coupled kinetic equations for the constituent of the mixture will be solved by using a discrete velocity method which takes into account the discontinuity of the distribution function of molecular velocities on the spherical interface. The hydrodynamic equations will also be solved in order to compare the results obtained via hydrodynamic and kinetic approaches and verify their reliabilities. The macroscopic properties of the gas mixture such as density, bulk velocity, heat flux and temperature around the spherical droplet will be presented in a wide range of the Knudsen number. (AU)