ONE-DIMENSIONAL EXPANSION OF A LAYER OF EVAPORATING MATTER INTO VACUUM

The one-dimensional problem of the expansion of material evaporated fr om the surface of a body by a short-time powerful energy pulse into a vacuum is studied. An asymptotically self-similar solution is construc ted for times which are long compared with the pulse width. Integral r elations for the mass, energy, and momentum of the evaporated material are employed together with the equations of gas dynamics; this makes it possible to find the form of the solution, differently related with the solution of the well-known problem of the expansion of a gas into a vacuum from a constantly acting source. The solution found physical ly corresponds to detachment of a cluster of evaporated material from the body and propagation of this cluster in space while spreading at t he same time. The results of the numerical modeling are in good agreem ent with this theoretical scheme.