Evaluation of Stochastic Simulations of Premixed Turbulent Jet Flames

Abstract

A theoretical investigation of round premixed turbulent jet flames is described, limited to the thin laminar-flamelet regime at neutral preferential diffusion conditions. Flame surface properties were numerically simulated using a statistical time series simulation of unburned gas properties along the flame surface in conjunction with a two-dimensional flame advection and propagation algorithm. Predictions were evaluated using existing tomographic and Rayleigh scattering measurements of flame surface properties and mean unreactedness in round jet flames having burner exit Reynolds numbers in the range 7000-39 200 and turbulence intensities relative to the laminar flame speed in the range 0.4-2.5. Simulated flame properties duplicated measured trends of the variation of flame surface properties and mean unreactedness with distance from the burner exit and relative turbulence intensity. However, effects of turbulence were underestimated—particularly near the flame tip due to the limitations of a two-dimensional simulation,