Have anybody used flamlet models for combustion. Is there any experimental evidence to use flamelet models for the various conditions of the turbulent flow(I mean everywhere in borghi diagram.) Any body can provide some references will be helpful. prasat

The theory behind flamelet model is the following: The flame is composed of a reaction zone seperating fuel/oxidizer for diffusion flames, or unburnt/burnt gases for premixed flames. The main limitation of this approach is when turbulence length- and time-scale are small compared to flame scales. When you reach this transition, the reaction is called "distributed" and the flame can not be modeled as a flamelet.

I am not aware that experimental measurments have shown that: - (1) he flamelet model can be used for the whole combustion diagram, and I don't think it can; - (2) "distributed" reactions occurs in traditionnal combustion device such as automotive engine, furnace... and therefore, the flamelet model is a (very?) good approach.

The following reference may give you more information on combustion diagram for

- premixed combustion Poinsot, Candel and Trouve "Application of direct numerical simulation to premixed turbulent combustion" in Prog. Energy Combustion Sci. vol21, pp 531-576, 1996.

- non-premixed combustion Thevenin, Renard, Fiechtner... "Regimes of nonpremixed flame/vortex interaction" 28th symposium on combustion (2000)