Study of the characteristics of cellular premixed flames on ceramic porous board for CH4/C2H6/co2 mixtures

This research is to study the characteristics of cellular premixed flames that are investigated on ceramic porous board with CH₄/C₂H₆/CO₂ mixtures (main compositions of natural gas in Thailand). Cellular flames are the phenomena caused by intrinsic instability induced by thermal expansion and of diffusive thermal instability due to preferential diffusion of mass versus heat. In lean combustion premixed flames, diffusive-thermal instability has a great influence on the flame shape, unsteady behavior, diffusive-thermal instability and thermal instability. To study the characteristics of cellular premixed flames, experimental apparatus consisted of mixing tube, ceramic porous board size, were designed. In this study, the shape and fluctuation of cellular premixed flames on a flat burner were also investigated. As the obtained results, the equivalence ratio for cellular premixed flames of CH₄/C₂H₆/CO₂ mixtures is 0.88-0.95. The results were shown that the size of cells and fluctuation from designed experiment as the instability intensity and elucidated the characteristics of air CH₄/C₂H₆/CO₂ flames.