Thermal characteristics of biogas flameless combustion in asymmetric meso-scale combustor.

Abstract

Thermal characteristics of non-premixed conventional flame and flameless mode at fixed fuel mass flow rate of biogas (60% CH4+40% CO2) in an asymmetric mesoscale vortex combustor. Axial and tangential oxidizer configurations are investigated in this paper. The three-dimensional form of governing equations, including the Realizable-k-e model and the eddy-dissipation, have been described to simulate temperature distribution and combustion stability. The effect of tangential oxidizer configurations on the temperature distribution is also explored. The non-premixed mesoscale flameless combustion with a low 10% O2 concentration is much more stable than the non-premixed conventional flame with a low 21% O2 concentration. The mesoscale flameless combustion mode has higher temperature homogeneity throughout than traditional flame. The maximum temperature of the conventional flame and flameless combustions were 1692 K and 1160 K, respectively.