Abstract
The effects of turbulence characteristics on local flame structure and the fractal feature of flame front are investigated by direct numerical simulations of hydrogen-air turbulent premixed flames propagating in three-dimensional homogeneous isotropic turbulence. The maximum heat release rate in high Reynolds number turbulence reaches to 1.4 times of that in the laminar flame, whereas fractal dimension of the flame surface are 2.3〜2.5 and independent on Reynolds number. The finite flame thickness causes the difference in the growth rate of flame surface area and turbulent burning velocity. This difference is collapsed by the ratio of the diameter of coherent fine scale eddy to the laminar flame thickness (D/δ_L). The inner cutoff scale, which is about 10 times Kolmogorov micro scale, also shows good correlation with D/δ_L
