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Ablative Rayleigh–Taylor instabilities are analyzed in terms of an incompressible fluid model. A generalized surface wave dispersion relation can be derived for arbitrary step-profiles with ablative mass and heat flow. A systematic overview on different regimes of ablative stabilization and growth reduction is given. Convective stabilization by the incoming and outcoming flows are found included as upper and lower limits on the instability growth. Applications for self-consistent steady-state conditions are discussed and a comparison is made with previous numerical work.

The problem of vaporization of a light-absorbing metal into vacuum is considered. It is assumed that the density of the light energy flux is not excessively large so that there is no significant absorption of light by the vapor. The expansion of the vapor thus occurs in a centered rarefaction wave. The obtained boundary conditions relate the values of the hydrodynamic variables in the rarefaction wave with the surface temperature of the metal. This is accomplished by an approximate solution of the gaskinetic problem of vapor motion within a thin film directly adjacent to the phase interface. The velocity of the vaporization front, the surface temperature of the metal, the temperature and velocity of the vapor, and the recoil momentum are calculated.

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The effects of temperature and pressure nonuniformities at evaporation on the properties of liquid–gas interface are studied by molecular dynamics (MD) simulation and thermodynamic perturbation method on the basis of the van der Waals theory of capillarity. The structure and properties of the interfacial layer of equilibrium and nonequilibrium Lennard-Jones (12-6) systems are investigated. The surface tension, the two-particle distribution functions, the density fluctuation correlation lengths, and the evaporation coefficients are calculated using MD simulation. It is shown that the presence of the temperature gradient at the interface due to evaporation leads to reduction of the surface tension. The results of MD simulations are in agreement with the results of thermodynamic approach.