Nonequilibrium Phenomena Behind Strong Shock Waves Generated in Superorbital Reentry Flight

摘要

The aerothermodynamic behavior behind the strong shock wave in air that is associated with a superorbital reentry flight was investigated experimentally. For the experiment, a free-piston-driven shock tube was used, and radiation from behind the shock front was investigated spectroscopically. Based on the spectroscopic measurement, the spatial distributions of the rotational/vibrational temperatures of molecules (N_2 and N_2~+), the electron excitation temperature of atomic nitrogen N, and the electron density were determined in the region behind the shock front. These results were reviewed by comparison with those previously determined for a nitrogen gas. It was found that there is remarkable resemblance in such distributions between air and a nitrogen gas. This suggests that the existence of molecular oxygen in air has only a minor influence on the behavior of temperatures of N_2, N_2~+, and N, and of the electron density.