Radiative gas-dynamic model of a continuous optical discharge in a gravitational field: quasi-optical approximation

Abstract

We consider a continuous optical discharge (COD) sustained by a vertically directed weakly focused CO2 laser beam, in a gravitational field. We used a full two-dimensional radiative gas-dynamic numerical model for the COD, which uses realistic quasi optics and takes refraction of the laser radiation in the plasma properly into account in the description of the laser beam propagation. The model is applied to calculate the parameters of the COD in a converging CO2 laser beam in free air atmosphere as a function of the laser power. We also demonstrate the effect of the selection of spectral groups, used in the multi-group diffusion approximation of the thermal radiation transport, on the model solutions.