Modeling a turbulent reactive flow with variable equivalence ratio: Application to a flame stabilized by a two-dimensional sudden expansion

In this paper, a numerical study of turbulent premixed flames of propane an d air is presented. The experimental configuration investigated (Besson et al, 1999) is a planar channel that incorporates a sudden expansion in a for m of two symmetrical backward-facing steps. Two lean mixtures of pro pane a nd air are injected in the upper and lower halves of the upstream part of t he channel. separated by a plate and in the present work, the fuel-air rati os of these two streams are different. The numerical model includes a secon d-order closure for Reynolds stresses and uses a modified Bray-Moss-Libby t heory to model a reactive turbulent flow with variable stoichiometry.