Turbulent premixed flames of propane/air and methane/air were studied on a stabilized Bunsen-type burner to investigate the interactions between turbulence and the structure of the flame front in the thin reaction zones regime. The fuel-air equivalence ratio was varied from 0.7 to stoichiometric for propane flames, and from 0.6 to stoichiometric for methane flames. The nondimensional turbulence intensity u'/SL covered the range from 2.7 to 24.1. The flame front data were obtained using planar Rayleigh scattering technique, and particle image velocimetry was used to measure the instantaneous velocity field of the flames. Thermal structure of the flame front was observed to change with increasing u'/SL. The reaction zone and preheat zone thicknesses increased modestly with nondimensional turbulence intensity in both propane and methane flames. Flame front curvature statistics displayed the same Gaussian-like distribution, which centered around zero for all the flame conditions studied. Flame surface density results exhibited almost no dependence on the nondimensional turbulence intensity. It was found that the flame curvature was able to broaden the flame front and reduce the flame surface density.
Investigation of dynamics of lean turbulent premixed flames by Rayleigh imaging
Untersuchung der Dynamik gasarmer, turbulenter, vorgemischter Flammen mittels Rayleigh-Abbildung
AIAA Journal ; 47 , 12 ; 2964-2973
2009
10 Seiten, 24 Bilder, 1 Tabelle, 38 Quellen
Aufsatz (Zeitschrift)
Englisch
Investigation of Dynamics of Lean Turbulent Premixed Flames by Rayleigh Imaging
Online Contents | 2009
|