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Fundamental mechanisms in premixed flame propagation via vortex-flame interactions: Numerical simulationsThe goal of the present study is to assess numerically the ability of single-step and two-step chemical models to describe the main features encountered during the interaction between a two-dimensional vortex pair and a premixed laminar flame. In the two-step mechanism, the reaction kinetics are represented by a first chain branching reaction A + X yields 2X and a second chain termination reaction X + X yields P. This paper presents the fundamental mechanisms occurring during vortex-flame interactions and the relative impact of the major parameters encountered in turbulent premixed flames and suspected of playing a role in quenching mechanism: (1) Influence of stretch is investigated by analyzing the contribution of curvature and tangential strain on the local structure of the flame. The effect of Lewis number on the flame response to a strained field is analyzed. (2) Radiative heat losses which are suspected to be partially or totally responsible for quenching are also investigated. (3) The effect of the diffusion of the radicals is studied using a two-step mechanism in which an intermediate species is present. The parameters of the two-step mechanism are entirely determined from physical arguments. (4) Precise quantitative comparisons between the DNS and the experimental results of Samaniego et al are performed. These comparisons concern the evolution of the minimum heat release rate found along the flame front during the interaction and the distribution of the heat release rate along the flame front.
Document ID
19950016023
Acquisition Source
Legacy CDMS
Document Type
Other
Authors
Mantel, Thierry
(Stanford Univ. CA, United States)
Date Acquired
September 6, 2013
Publication Date
December 1, 1994
Publication Information
Publication: Annual Research Briefs, 1994
Subject Category
Inorganic And Physical Chemistry
Accession Number
95N22440
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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