Hybrid rans/les turbulent premixed combustion tfc model

The problem of premixed combustion modeling at developed turbulence and fast chemistry for prediction of averaged combustion rates and species fluxes is so called turbulent combustion challenge. Two main reasons are at the base of the problem: 1. Instantaneous combustion takes place in thin and wrinkled sheets with non-laminar flamelets and developed small-scale wrinkle structures depending on molecully-turbulent-chemical coupling. This is unreserved by model equations and controls reaction rates; 2. The progress variable flux in flames is as a rule counter-gradient; in fact the flux is controlled not only by turbulence but also by gasdynamics pressure-driven effect (different acceleration of cold and hot volumes) producing the counter-gradient flux nature. Reynolds Averaged (RANS) and Large Eddy Simulation (LES) approaches have different potentials for overcoming these difficulties. The first problem has more justify solution in the context of RANS approach using an assumption of statistical equilibrium structures of the flamelets and sheet wrinkles that allows to express the effect of the unresolved coupling in terms of large-scale parameters governed by combustion model equations. The second problem has direct solution in frame of LES while in the context of RANS correct flux could be predicted only in frames of a special transport model

@InProceedings{ZB03a,
  author       = {Zimont, V. and Battaglia, V.},
  title        = {Hybrid rans/les turbulent premixed combustion tfc model},
  booktitle    = {Combustion And Atmospheric Pollution},
  pages        = {142--148},
  year         = {2003},
  editor       = {G. D. Roy and S. M. Frolov and and A. M. Starik and Torus Press},
  address      = {Moscow},
  keywords     = {Combustion, LES},
  url          = {https://publications.crs4.it/pubdocs/2003/ZB03a},
}