The comparison of the Riemann solutions in gas dynamics

In this paper, we compare two Riemann solution constructions of isentropic and non-isentropic gas dynamic equations, with the same initial values. We obtain that when rarefaction waves occur in the non-isentropic solution, the same family rarefaction waves occur in the isentropic solution, however, when advancing or reflected shock waves occur in the isentropic case, the same kind shock waves occur in the non-isentropic case. Moreover, by numerical calculation, it can be found that the wave intensities of the two solutions are quite close. Our conclusion reflects that almost non-isentropic gas dynamic process can be simulated by isentropic gas dynamic process in practice.