Experimental and theoretical analysis of vibrational relaxation regions in carbon dioxide

The density distribution in the relaxation regions of shock waves in carbon dioxide were determined in the Mach number range 1·4 to 4·0 using an interferometer. The over-all density ratios were found to agree with the theoretical final equilibrium values. Detailed analysis of the relaxation regions showed that the simple relaxation equation is inadequate, the relaxation frequency depending on departures from equilibrium as well as on temperature.