REVIEW OF CHEMICAL-KINETIC PROBLEMS OF FUTURE NASA MISSIONS .1. EARTH ENTRIES

The nonequilibrium thermochemical relaxation phenomena occurring behind a shock wave surrounding an object flying in the Earth's atmosphere have been studied intensely since the 1960s. Experimental observations of the phenomena have been made mainly using shock tubes. The paper concludes that the observed ionization behavior behind the normal shock wave in air at super-escape velocities is reproduced fairly well using a set of ionization rate coefficients given in the present work. Radiation intensity emitted from the nonequilibrium region is less than that emitted from the equilibrium region in the super-escape velocity ranges, i.e., radiation undershoot occurs.