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Knowledge of laws of strong evaporation is instrumental for the solution of a number of applied problems: the effect of laser radiation on materials (Gusarov and Smurov in Phys. Fluids 14:4242–4255, [1]), calculation of the parameters of discharge into vacuum of a flashing coolant (Larina et al. in Fluid Dyn. 31:127–133, [2]), etc.

The knowledge of the laws governing intense evaporation is important for vacuum technologies, exposure of materials to laser radiation, outflow of a coolant on loss of sealing in the protective envelope of an atomic power plant, and for other applications.

A semi-empirical model based on the linear kinetic theory was developed for intense evaporation. The extrapolated drops for pressure and temperature at the condensed phase surface were calculated through summing of linear and squared terms. The analytical dependencies were obtained for gas parameters in gas-dynamic zone as functions of Mach number, condensation coefficient, and the number of degrees of freedom for molecules of ideal gas. The calculations from semi-empirical model are in agreement with results from known analytical and numerical studies.

In recent years, there has been a growing interest in new fundamental and application problems focused on the study of strong phase transitions like evaporation and condensation. Problems of this kind arise in the study of many processes.

Nonequilibrium evaporation and condensation are important aspects in numerous fundamental and applied problems.

An approximate kinetic analysis of the process of intense evaporation has been carried out. The analytical solutions obtained for temperatures, pressures, and mass velocities of vapor agree well with the available numerical and analytical solutions. The evaporation limiting mass velocity has been calculated.

The Landau problem on the evaporation front stability is generalized to the case of finite thickness of the evaporating liquid layer. The analysis of the influence of additional factors, the impermeability condition of solid wall, and resulting pulsations of mass velocity is carried out.

Kinetic analysis of intensive evaporation based on the “method of balances of reverse molecular flows” has been performed. A technique of “drift velocity correction” for the simulation of the distribution function (DF) of the molecules incident onto the boundary is proposed. Analytical solutions of the equations of the balance of mass, momentum, and energy determining the macroscopic parameters of the evaporation process have been derived. The analytical solution is in good agreement with the results of numerical simulation of intensive evaporation performed using the numerical method.

Using an approximate method of analysis developed earlier for studying heat-exchange processes occurring with a periodic intensity, the problem of periodic evaporation of a liquid film from the surface of a heat-transfer wall is considered.