Experimental and Numerical Studies of Radiation Emission from High-Temperature Air Behind 10 km/s Shock Waves

In order to estimate the exact heat transfer from shock-heated air to the re-entering space vehicles, one needs the accurate understanding of its radiative characteristics.

The 10 km/s shock waves are produced by a free-piston, double-diaphragm shock tube, and the total and spectral-resolved radiation intensities of the shocked air are observed by using an image converter camera and a pair of photomultipliers.

The numerical analysis is carried out for one-dimensional, steady hypersonic flows with non-equilibrium chemical reactions of hot air, including the evaluation of radiation intensity.

The double-peak characteristic of radiation intensity for the shock waves above 10 km/s and the time-lag of radiation peak for different wave length are experimentally observed and qualitatively reproduced in numerical simulation.