A set of Direct Numerical Simulations (DNS) of turbulent jet flames is performed to investigate the effect of Reynolds number on flame characteristics. The simulations feature finite rate chemistry with 16 species and up to 22 billion grid points. The jet consists of a methane/air mixture with equivalence ratio φ = 0.7 and unburnt temperature of 800 K. The temperature and species concentrations in the coflow correspond to the equilibrium state of the burnt mixture. All the simulations are performed at 4 atm. The flame length, normalized by the jet width, decreases significantly as the Reynolds number increases. This is consistent with an increase of the turbulent flame speed due to the increased integral scale of turbulence. This behavior is typical of flames in the thin-reaction zone regime, which are affected by turbulent transport in the preheat layer. Statistics of stretch at the flame surface are investigated and the dependence of these quantities on the Reynolds number is assessed.
|Original language||English (US)|
|Title of host publication||11th Asia-Pacific Conference on Combustion, ASPACC 2017|
|State||Published - Jan 1 2017|