On the Phenomenon of Vapor-Phase Combustion of Alkali Metals

Abstract

Spectra of a burning spray of alkali metals have been analyzed. The Stark effect splitting of the hyperfine components of the sodium diffuse series lines without any applied external electric field is likely to have been obtained. On this basis, a semi-theoretical electrodynamic model of the vapor-phase combustion of single alkali metal particles (droplets) is presented. Such an electrodynamic combustion mechanism is characterized through great increase of both the flame stand-off distance and the lifetime of the burning alkali metal droplets. The total magnitude of the flame stand-off distance by the burning metal droplets is supposed to be composed of more than two-thirds action of the electrodynamic mechanism and smaller than one-third effect of the “ordinary” heat and mass transfer (the Spalding's combustion model). References to analogous spectral and electrical phenomena in papers on vapor-phase metal combustion of different authors are cited. In case of verification of the electrodynamic metal combustion mechanism in some control experiments, it could be purposely applied both in science and engineering.