Effects of burner structure on hydrogen/methane combustion in a porous medium burner

The lean combustion of hydrogen/methane mixtures within a highly porous inert medium was studied. A small-scale experimental burner system was built. The porous medium was made of partially stabilized zirconia with a porosity of ∼ 0.85. Four burners of different structures were used. In one of the flame structures, different starting flame position resulted in different thermal and stability characteristics. Addition of hydrogen in the fuel did not change the flame temperature greatly. However, it affected the flame speed and flame structure. The flame speed increased with the mole fraction of hydrogen in the fuel, especially for higher equivalence ratios. Factors accounting for this increase were elucidated. Original is an abstract.