A Numerical Study of Weakly Turbulent Premixed Combustion with Flame Speed Closure Model

Over the past years, the so-called Flame Speed Closure (FSC) model was shown to be a very promising tool for multi-dimensional simulations of premixed turbulent combustion in internal combustion and gas turbine engines. The laboratory tests and industrial applications of the model have been mainly limited to moderately turbulent flames. In the paper, three alternative versions of the FSC model, which yield different results at weak turbulence but similar results at moderate one, are discussed and numerically tested against recent experimental data reported by the Leeds [27,34] and Rouen [28] groups for expanding, statistically spherical, premixed, weakly turbulent flames. The computed and measured data on the mean combustion progress variable profiles, mean flame brush thickness development, and observed flame speeds are compared in order to assess and rank the submodels discussed.