A numerical method is developed for calculating the radiating axisymmetric flowfield accounting for nonequilibrium thermochemistry. Solutions of the flow with radiation are obtained in a fully coupled manner using a fully implicit time-marching method through a full block-matrix inversion. The method is used in calculating the radiation from the blunt-body shock layer in both air and carbon-containing airflows. The calculated results are compared with the experimental data obtained in a ballistic range at flight speeds of up to 13.4 km/s. For aluminum models, which do not ablate, the experimentally observed spectral features are qualitatively reproduced by the calculation, which assumes the shock layer to contain only the air species. For polycarbonate models, which ablate, additionally carbonaceous species must be included in the calculation in order to bring about qualitative agreement. Quantitative agreement is obtained for the ablating models only by accounting additionally for a blackbody radiation, produced possibly by spalled carbon particles.
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