Large-eddy simulation of a fuel-lean premixed turbulent swirl-burner

Large-eddy simulation of lean hydrogen–methane turbulent premixed flames in the methane-dominated regime

“…Previous studies by Fiorina et al [49] and Galpin et al [31] have shown that for FPI tabulated chemistry of methaneeair combustion based on steady laminar premixed flamelets, an appropriate choice for the progress of reaction variable is…”

“…In fact, just 10 species: CH 4 , O 2 , N 2 , H 2 O, CO 2 , CO, H 2 , H, OH and C 2 H 2 , are needed to accurately represent the mass and energy of methaneeair reactive mixtures [31]. However, in order to improve the prediction of the H 2 mass fraction and allow for the prediction of NO in H 2 -enriched methaneeair flames, a revised progress of reaction variable is needed and an enlarged set of species must be tracked.…”

“…Modelled balance equations are used to determine Y c and Y cv [20,30,31]. The modelled transport equation forỸ c has the form…”

“…The PDF of c is taken here to be a b-distribution [30,31] and can be constructed from the resolved or filtered progress variable,c, and its SFS variance, c v ¼ e cc Àcc. These two variables,c and c v , are directly linked to the progress of reactionỸ c and its SFS variance, Y cv .…”

Modeling chemical flame structure and combustion dynamics in LES

“…In such simple situations, all thermochemical quantities are related to a single progress variable related to the temperature or to a linear combination of chemical species. This tabulation chemistry method has been found very efficient and successful in laminar premixed and partially-premixed flames simulations [3,6,7] and to compute turbulent premixed and partially-premixed flames in both RANS (Reynolds Averaged Navier-Stokes equations) [8,9,10] and LES contexts [11,12]. As recently shown by Nguyen et al [13], very complex flame structures such as triple flames can also be accurately recovered by tabulated chemistry techniques.…”