Flame structure of super fuel-rich premixed flame

摘要

The flame structure and the combustion enhancement mechanism of the fuel-rich premixed flame using porous media have been investigated through a one-dimensional numerical analysis. The combustion reaction is represented by the Arrhenius reaction rate law, while the reaction rate of soot formation is based on Tesner's model modified by including the oxidation of soot. Since the soot consists of high-temperature particles, the combustion gas enthalpy is effectively converted into the thermal radiation emitted from them. Most of the radiant energy is absorbed by the porous medium located at the upstream side of the flame, and the absorbed energy is converted into the enthalpy increase in the unburned mixture. Therefore, the energy recirculation due to the combination of the upstream porous medium and the downstream soot layer is of primary importance in the present luminous flame.