DOI: 10.1615/ICHMT.2012.ProcSevIntSympTurbHeatTransfPal
ISBN Print: 978-1-56700-302-4
ISSN: 2377-2816
Effects of Lewis number on the curvature term of the Flame Surface Density transport equation for LES
ABSTRACT
A Direct Numerical Simulation (DNS) database of freely propagating statistically planar turbulent premixed flames with global Lewis numbers (Le) ranging from 0.34 to 1.2 has been used to analyse the statistical behaviours of the curvature term of the generalised Flame surface Density (FSD) transport equation in the context of the Large Eddy Simulation (LES). Lewis number is shown to have significant influences on the statistical behaviours of the resolved and sub-grid parts of the FSD curvature term. The existing models for the sub-grid curvature term do not adequately capture the statistical behaviours of the sub-grid curvature term for flames with Le <<1 and thus new models are proposed for addressing non-unity Lewis number effects.