Roles of displacement speed on evolution of flame surface density for different turbulent intensities and Lewis numbers in turbulent premixed combustion

摘要: Direct numerical simulations (DNS) are conducted in 3D to investigate the evolution of flame surface density (FSD) turbulent premixed combustion. A parametric study is performed with respect intensity and Lewis number all component terms FSD transport equation. higher leads a burning velocity due increased area, while mean consumption speed remains close laminar speed. lower velocity, increases both total area There two source govern FSD: tangential strain propagation term, given as product displacement curvature. The rate varies linearly intensity, but shows no noticeable dependence on number. correlation between curvature does not depend significant influence term decreases increasing become larger negative sink rear brush elements smaller radii speeds. positive front an produce more through diffusive thermal instability.