Reaction-limited evaporation for the color-gradient lattice Boltzmann model

Abstract

We present a method to achieve reaction-limited evaporation for the color-gradient lattice Boltzmann multicomponent model. Our approach involves a systematic way to remove fluid mass from the interface region in order to achieve evaporation rates similar to those in a reaction-limited regime. Through various tests, our method demonstrates accurate and consistent results for different interface shapes across a wide range of evaporation flux magnitudes. A single free parameter is required to choose the evaporation sites where fluid mass is exchanged between the components. We find that at unit density ratio, this single parameter allows for the correct description of an arbitrarily shaped interface with an error of less than 5%. For density contrasts, accurate results are observed for lower evaporation flux magnitudes and density ratios. Our proposed method can be applied to isothermal reaction-limited scenarios, such as evaporation in pure vapor or under a gas draft. It can also handle weakly space-time-dependent fluxes, making it suitable for specific non-isothermal applications such as drop evaporation from heated substrates.