Effects of pressure and nitrogen dilution on flame/stretch interactions of laminar premixed H2/O2/N2 flames

The effects of positive flame stretch on the laminar burning velocities observed in freely (outwardly)-propagating spherical laminar premixed flames involving H2/O2/N2 mixtures at various pressures and nitrogen dilutions were studied both experimentally and computationally. The experiments were carried out at normal temperature and fuel-equivalence ratios in the range 0.45-4.00, pressures in the range 0.35-4.00 atm, volumetric oxygen concentrations in the non-fuel gas in the range 0.125-0.210, Karlovitz numbers in the range 0.0-0.6, and laminar burning velocities in the range 100-3000 mm/s. The major conclusions of the study are outlined. (AIAA)