Influence of turbulence and convection on the output of a high-power CO2 laser with a fast axial flow

Abstract

A high-power CW CO2 laser with a fast axial flow is investigated experimentally and theoretically. The gas flow is controlled by several different designs of the discharge tube which is either made of glass of cascaded metal discs. A high laser-gas purity is achieved by a Pt-Rh catalyst placed in the main flow. A laser power of 1.2 kW m-1 with 30% efficiency is reached. The active medium is described by assuming a five-temperature model and balancing the quantum densities of vibrational states of the CO2 and N2 molecules. This system of basic equations is completed by the mass, momentum and energy continuity equations. A model, method of solution and theoretical and experimental results are described and presented. The experimental results are in very good agreement with the theoretical predictions within a broad range of parameters.