Rayleigh–Taylor stability with mass and heat transfer

Abstract

A nonlinear analysis of the Rayleigh–Taylor stability of two thermally conducting fluids is presented. Mass transfer across the interface due to the evaporation and condensation process is explicitly taken into account. The method of multiple scale expansion is employed for the analysis. The stability criterion is expressible in terms of various competing parameters representing the equilibrium heat flux, latent heat of evaporation, vapor pressure, gravity, surface tension, densities of the fluids, and thermal properties of the fluids. It is found that when the heat flux is strong enough and when the heat transfer mechanism is efficient enough, the system can be stabilized in the regimes where it would be linearly unstable. The study has also shed light on the validity of the quasi-equilibrium approximation employed in a previous nonlinear study of the stability problem. The implication for the phenomenon of boiling heat transfer is also discussed.