Calculation and analysis of the kinetic properties and transport coefficients of electrons in premixed flames under applied voltage

The kinetic properties and transport coefficients of electrons in premixed flames are computed via solutions to the Boltzmann kinetic equation. The case of high electric field strength resulting in high-energy, non-thermal electrons is analysed in detail due to its relevance to studies of flames under applied voltage. It is found that in the non-thermal regime, electron kinetic properties (i.e. collision frequency, mean free path, and mean energy) and transport coefficients (i.e. mobility and diffusion coefficient) are mostly insensitive to mixture composition and approximately constant across the flame, but depend greatly on the electric field strength. In the thermal limit, electron properties vary severalfold across the flame due to the spatially inhomogeneous concentration of water vapor. The observed trends are largely independent of equivalence ratio. A practical approach to estimating the plasma regime in studies of electric field effects on flames is proposed.