Rarefied Gas Flow Reflection from a Wall with an Orifice and Gas Outflow into a Vacuum

The unsteady two-dimensional problem of the reflection of a uniform supersonic rarefied-gas flow incident normal on a wall with an orifice and the gas outflow through the orifice (slot or channel) is solved on the basis of the kinetic S-model. The slot influence on the reflection nature, the velocity of the shock wave reflected from the wall, and the formation of a gas jet flowing out into a vacuum is studied as a function of the incident flow velocity, the gas rarefaction degree, and the conditions imposed on the wall. The effect of the wall thickness, that is, the length of the channel, through which the gas flows out, is also investigated. The gas flow rate through the orifice is calculated as the main integral characteristic. The attainment of steady reflection regime in the outflow process is traced. The kinetic equation is solved numerically using the conservative difference method of the second order with respect to all variables.