対向噴流乱流予混合火炎の構造〔熱工学, 内燃機関, 動力など〕

抄録

In this study, a new ceramic-opposed jet burner was designed to ensure the adiabaticity of the flame. In the opposed jet turbulent premixed flame, the concentrations of stable species and temperature distributions and their structures have been investigated. The opposed jet burner flame can persist far beyond the stretch rate, at which point the wrinkled laminar flame is extinguished. The results show that the flame structures consist of stretched stringy vortices involving various reacting species (e.g., C₃H₃, hydrocarbonsns, O₂) which are referred to as the distributed reaction zones, and that the flames are divided into two categories : (1) transition flame from a wrinkled laminar flame to a distributed reaction zone, and (2) a fully developed distributed reaction zone. The structure of the distributed reaction zone depends mainly on the mixture supply velocities and is insensitive to the equivalence ratios. The stretched stringy vortices of the distributed reaction zone eradicates the nonuniformity of temperature and concentration fields. The hydrocarbon species as well as fuel are consumed completely in the distributed reaction zone, and almost complete combustion is achieved.