Effect of Radiation upon the Post-Shock State

Abstract

The effect of radiation upon the state of the gas behind a strong shock wave is studied. The equations of radiation gas dynamics are used, and it is shown that the two characteristic times, τ the time for radiative cooling, and λ/c, the mean time of photon flight, determine whether a strong shock wave is optically thin. The steady-state shock jump conditions for hydrogen are determined for plasmas which are optically thin, and they are compared with the Saha equilibrium solutions. The temperature decay, plasma velocity, and density behind strong shock waves are determined for the case of an optically thin bremsstrahlung radiating plasma. The time-dependent equations of the motion of a fluid interacting with radiation are examined and the radiative terms in these equations are presented as part of a general solution of the time-dependent radiative transfer equation.