Systematically reduced rate mechanisms and presumed PDF models for premixed turbulent combustion
- Cambridge University, Cambridge CB2 1PZ (United Kingdom)
- Laboratoire de Combustion et de Detonique - UPR9028 CNRS, ENSMA, 86961 Futuroscope (France)
- University of California San Diego, La Jolla, CA (United States)
The use of reduced kinetic mechanisms in models for turbulent premixed flames, at large but finite Damkoehler numbers, is described. Taking as examples the two cases of hydrogen-air and methane-air systems for which there exist reduced kinetic schemes characterized by two independent scalar variables only, it is shown that the mean chemical production rate can be in a general way expressed as the product of a mixing factor, depending on the segregation of species due to turbulence, with a reaction rate factor. In this latter factor the probability density function (PDF) of the two scalars appears only as a constant integral quantity. The extension of this analysis to systems involving more than two independent scalars is envisaged. The general result is applied to the two specific cases of interior PDF's modelled by (i) a single Dirac delta function and (ii) a laminar flamelet. (author)
- OSTI ID:
- 21285632
- Journal Information:
- Combustion and Flame, Journal Name: Combustion and Flame Journal Issue: 3 Vol. 157; ISSN CBFMAO; ISSN 0010-2180
- Country of Publication:
- United States
- Language:
- English
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