Effect of alkali-metal atoms on vibrational relaxation in molecular-gas flows

Systems containing carbon dioxide, molecular nitrogen, and small admixtures of alkali-metal atoms are used in magnetohydrodynamic generators, gas lasers, and propulsion units. The present paper obtains quantitative data on vibrational disequilibrium in the system CO2-N2-A expanding in a supersonic nozzle. The effect of mixture-expansion rate on the variation of vibrational temperatures when alkali metals are added is studied. It is found that the electron excitation temperature is not equal to the N2 vibrational temperature. Even small additions (.01 % of total concentration) of alkali metals have a significant effect on vibrational relaxation in the gas system.