The problem of solid body vaporization into vacuum is considered. Evolution of distribution function is governed by kinetic equation, whose right hand-side is equal to the Bhatnagar-Gross-Krook integral of collisions and the real integral of collisions of Boltzmann. Inadequacy to real physical process of collisions is numerically demonstrated, which occurs due to the fact that frequency of collisions does not depend on the velocities of collided particles. Due to the use of the Boltzmann equation the structure of the surface layer is investigated for which three zones for macroparameters are numerically established, these are: the zone of intense collisions, where local thermodynamic equilibrium is setting in, the transitional area and the zone where the flow is collisionless.

Mathematical modelling in actual problems of science and technics