Effects of thermal expansion on moderately intense turbulence in premixed flames

نویسندگان

چکیده

This study aims at analytically and numerically exploring the influence of combustion-induced thermal expansion on turbulence in premixed flames. In theoretical part, contributions solenoidal potential velocity fluctuations to unclosed component advection term Reynolds-averaged Navier–Stokes equations are compared, a new criterion for assessing importance effects is introduced. The highlights ratio dilatation laminar flame large-scale gradient root mean square (rms) turbulent brush. To support study, direct numerical simulation (DNS) data obtained earlier from two complex-chemistry, lean H 2 –air flames analyzed. line with criterion, even sufficiently high Karlovitz numbers, results show significant second moments upstream within particular, DNS demonstrate that (i) rms velocities comparable unburnt gas close leading edge brush (ii) conditioned entire Moreover, affects not only but one. latter manifest themselves negative correlation between or counter-gradient behavior scalar flux. Finally, turbulence-in-premixed-flame diagram sketched discuss various ranges spectrum.

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ژورنال

عنوان ژورنال: Physics of Fluids

سال: 2022

ISSN: ['1527-2435', '1089-7666', '1070-6631']

DOI: https://doi.org/10.1063/5.0123211