Some remarks on the dynamics of deformable bodies.
factor of 2 appear in the nonequilibrium region, thus illustrating the uncertainties regarding the behavior of species other than CN. Except for their equilibrium levels, the curves for N and NO are omitted from the figure for clarity, but their behavior in time and magnitude is similar to that of 0 and CN, respectively, and in good agreement with the 16-reaction system. It is also shown in Ref. 1 that both the experimental data and the computed results follow binary scaling laws in the nonequilibrium region. Hence, the effects of varying ambient density are accurately reproduced, and it is only necessary to compare results obtained with the two chemical models at other shock speeds and gas mixtures. For these comparisons, the magnitude and time of the peak intensity are indicative of the adequacy of the 9-reaction system, and if they agree with the data, the remainder of the intensity profile is also found to be matched. The variation of the peak CN intensity over the range of shock speeds considered was computed using the 9-reaction system of Table 1 and is compared with computations using the 16-reaction system and experimental data in Fig. 2. The results show the predictions made with the 9and 16-reaction systems to be similar in the speed range from 5.8 to 7.0 km/sec, which is that of primary interest for Mars entry. The computed and experimental times to peak CN intensity are shown in Fig. 3. Again, the results for both reaction systems are similar and provide a good approximation to the experimental data. The foregoing results indicate that the predictions based on the simplified chemical model of 9 reactions presented in Table 1 are adequate for estimating the nonequilibrium radiant emission of CN in shock-heated mixtures of C02 and N2 for the range of speeds of current interest for entry into the Martian atmosphere.