A New Kinetic Model for Assessing the Performance of Advanced CO₂ Gasdynamic Lasers

Abstract

A theoretical analysis of CO2 gasdynamic laser ( CO2-GDL) performance using a six-temperature model is described in this paper. This model has specifically included vibrational transfer processes associated with vibrational non equilibrium of O2 and H2O so that the kinetic behaviors of these species in an active laser medium can be properly assessed. The calculation carried out with this model showed that presence of O2 in the laser medium together with H2O reduces the population inversion. Consequently, under the condition where the concentration of H2O was ∼4 mol%, every additional percent of O2 was found to be about one percent reduction in the small signal gain of a CO2-GDL. The calculation resulted in good agreement with experimental studies in the variation of the small signal gains as well as vibrational temperatures for various laser gas composition.