Structure of Lean Turbulent Partially-Premixed Flames Stabilized in a Co-Axial Jet Flame Burner

Soot Volume Fraction Measurements in the Soot-forming Regions of Ethylene-AirTurbulent Partially-premixed Flames

“…The same burner has been used for studying various aspects of turbulent partially-premixed flames in this laboratory Lee and Mitrovic, 1997), and details have been described therein. The burner was of modular design and consisted of two mixing chambers, filled with glass beads.…”

“…It has been shown that the flame length, lift-off height and flame stability could be effectively controlled by changing the amount and injection point of premixing air. Also, from a base premixed flame, the effect of adding air to this premixed flame to cause local leaning of the equivalence ratio was considered (Lee and Mitrovic, 1997). Flame stability limit measurements showed that the lean burning limit of these flames could be significantly extended in this flame configuration, and also Rayleigh scattering measurements indicated that the local temperature probability density function became broadened, representing a departure from bi-modal pdf's associated with premixed flames.…”

“…These results point out some important trends in the sooting characteristics as a function of partial premixing parameters. Recent experimental studies of partially premixed combustion have included those of Rokke et al (1994), Gore and Zhan (1996), and those from this laboratory Lee and Mitrovic, 1997;and Mitrovic and Lee, 1997). No" emission and global flame characteristics have been investigated in turbulent partially premixed flames, in which the fuel stream has been diluted with air to lower the equivalence ratio (Rokke et al, 1994).…”

“…The work in this laboratory has considered various aspects of turbulent and laminar partially premixed flames, including global flame structure , flame stability Lee and Mitrovic, 1997), temperature distributions (Lee and Mitrovic,1997) and soot formation characteristics of laminar partially premixed flames (Mitrovic and . We have looked at the dynamic effects of the fuel and air mixing in a co-axial jet flame burner where both the amount and the injection point of premixing air could be varied .…”

Lean partially premixed turbulent flame equivalence ratio measurements using laser-induced breakdown spectroscopy

“…The high turbulence level associated with the large disk, ds = 45 mm, resulted in an increase in the entrainment of the hot product gas and flame radicals towards incoming reactants, elevating the chemical reaction rate, and hence, it helped to stabilize the flame [63][64][65]. Furthermore, this kind of mixing between the products and reactants diluted the mixture fraction of disk, ds = 45 mm, as compared to that of disk, ds =25 mm.…”