Specific features of unsteady exhaustion of a gas–particle medium into vacuum

Resumo

Results of an analysis of two-dimensional unsteady exhaustion of a one-velocity gas–particle medium into vacuum for limiting equilibrium cases of heat transfer between the phases are reported. Domains of existence of a one-dimensional Riemann wave and a lateral expansion wave, as well as boundaries of the flow expansion region are determined. Under thermal equilibrium conditions, the reverse flow is found to occupy a large domain extending beyond the boundaries defined by angles of expansion for an ideal gas and for a gas–particle mixture with thermally insulated phases. Exhaustion of a nonequilibrium (in terms of velocities and temperatures) two-phase medium into vacuum is numerically simulated. It is demonstrated that a barrel-shaped structure with wave expansion of the gas and a combined discontinuity in the expanding gas–particle mixture is formed.