Numerical stduy of the effect of gas nonideality on shock wave focusing in a channel with a hemispherical end

A physical and mathematical model, computational algorithms, and results of calculations of focusing and reflection from a flat bottom of a shock wave propagating in a channel with the hemispherical end filled with high-temperature air are presented. Three flow models are studied: ideal, frozen, and equilibrium. It is shown that the end face coordinate has little effect on the parameters of the reflected shock wave, which can be used to set the boundary conditions. The use of the ideal model leads to significant differences in the values of temperature and pressure both near the flat bottom and in the entire channel. The results of calculations according to the frozen model are close to the equilibrium results at a distance from the bottom but give a significantly overestimated temperature near it.