Premixed Combustion of Liquid Fuel by Air Bubble Blowing

Abstract

Premixed combustion of liquid fuel (kerosene) by air bubble blowing was attempted, which is a new method originated from the reverse concept of spray combustion. Setting a porous ceramic plate above the foam layer formed by blowing air into fuel made it possible to stabilize premixed flames on the plate. For most conditions examined the surface of this flame-holding plate was heated and became red-hot, which was effective for promoting fuel evaporation. The dependencies on air flow rate and equivalence ratio of temperature distributions inside and outside the plate were measured and examined in comparison with the cases for uniform gas mixtures. The burned gas was also analyzed in the downstream region and it was found that CO/CO₂ level and UHC concentration were less than the regulation values over a wide range of combustion intensities up to the turn-down ratio of 4.8, and NO_x concentration was nearly on the same level as other combustors for domestic use.