A comparative
analysis of performance of three different porous
ceramic materials used as a flame-contained media within a flow-stabilized
combustor is presented within this work. The experiments were performed
at a constant air flow rate and variable methane flow rates. α-Al2O3, MgO–ZrO2, and SiC highly
porous ceramics were used as the porous media. All three porous media
used in the study had equal dimensions and porosity and were located
in the same fixed position within the combustion chamber. Characterization
of the structure of porous media before experimentation was performed
using multiple methods. During combustor operation, temperature profiles
were collected along with optical and acoustic emissions and correlated
with the composition of the gaseous methane/air mixtures. It was found
that, while SiC enables the highest temperatures within the combustion
chamber at higher equivalence ratios, the ionically conducting MgO–ZrO2 porous media greatly expands the lean limit of combustor
operation and is, thus, the preferred porous media material for lower
equivalence ratio operation.