Turbulent premixed combustion; Further discussions on the scales of fluctuations
Abstract
The prediction of turbulent combustion is classically performed by numerical integration of modeled equations. For each existing approach, a crucial quantity is a time scale for the destruction of temperature (or concentration) fluctuations. Usually, this time scale is simply taken as proportional to the corresponding time scale for velocity fluctuations, but the question of the influence of the reaction on this scale arises, and has already been discussed. The authors discuss this point in the particular case of wrinkled premixed flames. Algebraic closure formulas, as well as closures based on the socalled {epsilon}{sub y} equation, or on the equation for the flame surface by unit of volume of Marble and Broadwell, are proposed and discussed. It is found, in particular, that in the case of wrinkled flames with infinite Damkohler and Reynolds numbers the reaction does not play any direct role on the time scale.
 Authors:
 (Laboratoire de Thermodynamique, UA CNRS No. 230, Faculte des Science et des Techniques de Rouen, 76130 MontSaint Aignan (FR))
 Publication Date:
 OSTI Identifier:
 6806603
 Alternate Identifier(s):
 OSTI ID: 6806603
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Combustion and Flame; (USA); Journal Volume: 80:3
 Country of Publication:
 United States
 Language:
 English
 Subject:
 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; 42 ENGINEERING; FLAMES; COMBUSTION KINETICS; FUELS; MIXTURES; TURBULENT FLOW; EQUATIONS; REYNOLDS NUMBER; TEMPERATURE GRADIENTS; CHEMICAL REACTION KINETICS; DISPERSIONS; FLUID FLOW; KINETICS; REACTION KINETICS 400800*  Combustion, Pyrolysis, & HighTemperature Chemistry; 420400  Engineering Heat Transfer & Fluid Flow
Citation Formats
Borghi, R. Turbulent premixed combustion; Further discussions on the scales of fluctuations. United States: N. p., 1990.
Web. doi:10.1016/00102180(90)901062.
Borghi, R. Turbulent premixed combustion; Further discussions on the scales of fluctuations. United States. doi:10.1016/00102180(90)901062.
Borghi, R. Fri .
"Turbulent premixed combustion; Further discussions on the scales of fluctuations". United States.
doi:10.1016/00102180(90)901062.
@article{osti_6806603,
title = {Turbulent premixed combustion; Further discussions on the scales of fluctuations},
author = {Borghi, R.},
abstractNote = {The prediction of turbulent combustion is classically performed by numerical integration of modeled equations. For each existing approach, a crucial quantity is a time scale for the destruction of temperature (or concentration) fluctuations. Usually, this time scale is simply taken as proportional to the corresponding time scale for velocity fluctuations, but the question of the influence of the reaction on this scale arises, and has already been discussed. The authors discuss this point in the particular case of wrinkled premixed flames. Algebraic closure formulas, as well as closures based on the socalled {epsilon}{sub y} equation, or on the equation for the flame surface by unit of volume of Marble and Broadwell, are proposed and discussed. It is found, in particular, that in the case of wrinkled flames with infinite Damkohler and Reynolds numbers the reaction does not play any direct role on the time scale.},
doi = {10.1016/00102180(90)901062},
journal = {Combustion and Flame; (USA)},
number = ,
volume = 80:3,
place = {United States},
year = {Fri Jun 01 00:00:00 EDT 1990},
month = {Fri Jun 01 00:00:00 EDT 1990}
}

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