Unifying the Interfacial Conditions of Thin Films
Thin films forming by adsorption and condensation, or undergoing transient evaporation and desorption, are typical examples of systems with moving boundaries. For treatment of transport processes in such a film, the conditions at the film surface need to be specified. In the present paper the equations for the interfacial mass and heat fluxes along with the interfacial conditions have been deduced for a multi-component, non-isothermal film from ordinary balances. The relationship describing the interactions between the phases across the interface couples the temperature, composition and velocity fields in the phases. As a boundary condition, it governs the profile of the film thereby taking into account the movement of its surface.