Modeling of scalar dissipation in partially premixed turbulent flames

Journal Article · Sun Apr 15 04:00:00 EDT 2007 · Combustion and Flame

DOI:https://doi.org/10.1016/J.COMBUSTFLAME.2006.11.004· OSTI ID:20880650

Mura, Arnaud; Robin, Vincent; Champion, Michel ^[1]

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1. LCD UPR 9028 du CNRS, ENSMA Poitiers (France)

The question of the closure of scalar dissipation terms for both passive and reactive scalars is addressed. In a first step of the analysis, modeled transport equations for the mean reactive scalar dissipation are reviewed in the two limiting cases of (i) the flamelet regime and (ii) the thickened flame regime of turbulent premixed combustion. The corresponding asymptotic algebraic closures obtained for large values of the turbulent Reynolds Re{sub T}, i.e., eddy breakup and linear relaxation model for scalar fluctuations decay, are recovered. These two limiting closures are then used to build a general algebraic closure of the mean dissipation of reactive scalar fluctuations. The resulting expression is applicable to modeling turbulent premixed combustion whatever the combustion regime. In a second step, the same strategy leads to the development of an algebraic closure for partially premixed situations, a situation requiring the use of at least two variables. In this process, a relationship between reactive, passive, and cross-scalar dissipations is derived. This general result is then simplified to elaborate new closed expressions of mean dissipation terms. There are applicable to a wide range of conditions, from premixed to partially premixed situations and from the flamelet to the thickened flame regime. (author)

• OSTI ID: 20880650
• Journal Information: Combustion and Flame, Journal Name: Combustion and Flame Journal Issue: 1-2 Vol. 149; ISSN CBFMAO; ISSN 0010-2180
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
ASYMPTOTIC SOLUTIONS
COMBUSTION
CONVERGENCE
FLAMES
FLUCTUATIONS
MATHEMATICAL MODELS
RELAXATION
REYNOLDS NUMBER
SCALARS
SIMULATION
TRANSPORT THEORY
TURBULENCE