Radiation modeling with direct simulation Monte Carlo

Improvements in the modeling of radiation in low density shock waves with direct simulation Monte Carlo (DSMC) are the subject of this study. A new scheme to determine the relaxation collision numbers for excitation of electronic states is proposed. This scheme attempts to move the DSMC programs toward a more detailed modeling of the physics and more reliance on available experimental data. The new method is compared with the current modeling technique and both techniques are compared with available data. The differences in the results are evaluated. The test case is based on an AVCO-Everett shock tube experiment, a 10-km/s standing shock wave in air at 0.1 Torr. The new method agrees with the available data as well as the results from the earlier scheme and is more easily extrapolated to different flow conditions.