Advanced Approach for Radiation Transport Description in 3D Collisional-radiative Models

The description of radiation transport phenomena in the frames of collisional-radiative models requires the solution of Holstein-Biberman equation. An advanced solutuion method for 3D plasma obejcts is proposed. The method is applicable for various line contours in a wide range of absorption coefficients. Developed approach is based on discretization of the arbitrary plasma volume on a Cartesian voxel grid. Transport of photons between the cells is computed using the ray traversal algorithm by Amanatides [1]. Solution of the particle balance equations with computed in advance radiative transfer matrix is demonstrated for various typical arc shapes, like e.g. free-burning arc and cylindric arc. Results are compared with corresponding calculations using previously developed approaches. As the method is suited for finite geometries and allows for a strict solution of the radiation transport equation, applicability ranges of previous approximations can be specified

DUST PARTICLE CHARGE DETERMINATION IN CONSIDERATION OF NON-LOCAL EFFECTS IN A STRATIFIED GLOW DISCHARGE

A new theoretical method of dust particle charge determination is provided. This method is based on the calculation of the ion and electron fluxes on the dust particle surface in a spatially periodic strata field. The electron flux is calculated through the non-local electron distribution function (EDF), which is formed by inhomogeneous strata potential. The comparison between proposed theoretical method and the traditional method of using Maxwell EDF for dust particle charge calculation is done87-8

DUST PARTICLE CHARGE DETERMINATION IN CONSIDERATION OF NON-LOCAL EFFECTS IN A STRATIFIED GLOW DISCHARGE

87-87A new theoretical method of dust particle charge determination is provided. This method is based on the calculation of the ion and electron fluxes on the dust particle surface in a spatially periodic strata field. The electron flux is calculated through the non-local electron distribution function (EDF), which is formed by inhomogeneous strata potential. The comparison between proposed theoretical method and the traditional method of using Maxwell EDF for dust particle charge calculation is don

N2(a‘ 1Σg+) metastable collisional destruction and rotational excitation transfer by N2

Quenching and rotational coupling rate coefficients have been measured for the J=4–10, v=0 levels of the a″ 1Σg+ metastable state of N2 in collisions with ground state N2. Laser absorption is used to monitor the population of rotational levels of the a″ 1Σg+ state following depletion of the population of one or more levels by optical pumping to other states. The observed time dependence of the recovery of population of the perturbed level and the collision induced growth and decay of the populations of adjacent levels are interpreted in terms of quenching to other electronic levels and excitation exchange among adjacent rotational levels. For the J=6, v=0 level of the a″ 1Σg+ state the rate coefficients extrapolated to zero discharge current at 300 K are 2.3±0.1×10−16 m3/s for electronic quenching and 1.1±0.6×10−16 m3/s for excitation transfer to the J=4 and J=8 levels in collisions with N2. Very similar rate coefficients were obtained for the J=4, 7, and 8 levels