Evaporation in a Binary Liquid Falling Film

Thin liquid films are ubiquitous in both nature and industrial applications. We focus on the stability and dynamics of a fluid film of two miscible liquids falling along an inclined plane with one component is evaporating at the free surface. We utilize Navier-Stokes equation, heat equation and vapor-liquid jump conditions at the free surface. We non-dimensionalize the system and apply perturbation theory to obtain evolution equations for film and concentration. As the film travels, the film profile overlaps with the concentration profile, and three types of sharp transition will occur in the film profile: a. film peak speeds up and moves forward, b. film peak moves backward and then moves forward again, c. film will be slowed and two local peaks will form in the film