Theory of high subsonic flow CO electric discharge lasers

A self-consistent model for high subsonic flow electric discharge CO laser systems with coincident optical and flow axes is presented. The model employed here couples the kinetics of the electrons and heavy particles with the optical and fluid dynamic processes in the laser system. The resulting integro-differential system of equations governing this multi-level system is solved by an exact numerical scheme. The effects of composition, total mass flow rate, inlet temperature and pressure, mirror reflectivity and input power on the maximum average small signal gain coefficients, the intensities and the efficiency are examined. The results indicate that for a given input power and N2 fraction, the efficiency increases by reducing the inlet temperature and increasing the velocity and/or the fraction of CO. Moreover, transitions on the lower vibrational bands can be obtained at the expense of lower efficiencies by reducing the CO fraction.