As the greenhouse emission problems, the combustion of hydrogen-air (H2-air) mixtures was investigated to consider the reduction of carbon dioxide (CO2) and the replacement of nitrogen N2 with CO2 was studied to reduce nitrogen oxide (NOx). Normally, the flame speed of H2-O2 mixtures is very fast thus it is necessary to control the limit of mixtures with CO2 addition as H2-O2-CO2 combustion. The limit of hydrogen was set and replaced by CO2 with O2:CO2 ratio as 1:3, 1:3.76 and 1:4 for this study. In this study, the combustion of H2-O2 -CO2 on flat burner at equivalence ratio ϕ=0.5 was investigated for 10, 15 and 20 L/min of flow rate of mixtures. When the ratio of CO2 increases, the power spectral density is lower, the ring of attractor is more complicated and the cellular flame become larger because the decrease of hydrogen replaced by CO2 affects the diffusive-thermal instability. Moreover, as the flow rate of mixtures increases, the power spectral density increases, and the reconstructed attractor and cell size become smaller due to decreasing of instability. The results show that the variation of CO2 and the flow rate of mixtures affect the instability of cellular premixed flames on flat burner.
Effect of Chemical Interaction on Flame Extinction in Interacting H2-air and CO-air Premixed Flames
