Gravity effects on steady two-dimensional partially premixed methane–air flames

Under normal-gravity conditions the flame heat release produces both flow dilatation and buoyancy effects. While it may be possible to minimize gravitational effects in a fully premixed flame by isolating buoyancy effects to the lower-density postflame region or plume, this cannot be accomplished in nonpremixed flames. It is known that partially premixed flames can contain two reaction zones, one with a premixed-like structure and the other …