Spatially resolved LAAS diagnostics of a free-burning ar arc: Analysis of line broadening

摘要: Abstract Spatially resolved laser atomic absorption spectroscopy (LAAS) diagnostics are applied to a free-burning DC arc in argon at atmospheric pressure. The novel LAAS apparatus is capable of mode-hop free wavelength tuning over the larger range than conventional systems (up 300 GHz present work). It allows for measurements both coefficient and spectral line profile continuously from hot center non-equilibrium wings. results such presented this work with emphasize on combined analysis absorption, which gives densities excited atoms, broadening, delivers information either electron density (in case Stark broadening) or neutral atom van der Waals broadening). Contributions by different broadening mechanisms (Stark, Doppler, Waals, Resonance) separated analyzed. Experimentally retrieved temperature profiles electrons atoms compared predictions self-consisted nonequilibrium model. widths Ar I lines 750.38, 751.46, 763.51 nm obtained 11000–18000 K aim extend rather scarce data those lines. measured existing values literature theoretical predictions.