An experimental estimation of flame surface density and mean reaction rate in turbulent premixed flames

Deschamps B., Boukhalfa A., Chauveau C., GÖKALP İ., Shepherd I., Cheng R.

Symposium (International) on Combustion, cilt.24, sa.1, ss.469-475, 1992 (Scopus)

Özet

An experimental method based on laser induced Rayleigh scattering for premixed turbulent flames has been developed to obtain a more complete description of the scalar field in the time domain. The Rayleigh scattering data are analyzed to infer the flamelet crossing frequency and the flamelet transit time. An important consequence of these measurements is the development of a means to determine the mean reaction rate at a point within the flame brush without making drastic assumptions about the instantaneous flamelet structure and geometry. The method has been applied to methane-air open conical turbulent premixed flames in the flamelet regime, where the scalar field temporal statistics are determined on the centerline. The variation of the flamelet transit times with the flame and flow parameters is discussed. It is shown that the cold flow integral length scale is the regulating parameter of the flamelet surface to volume ratio for the investigated turbulent combustion regime. The local mean reaction rate is estimated directly from the Rayleigh scattering data. © 1992 Combustion Institute.