Abstract
Turbulent burning velocity of spherically propagating flame kept increasing with flame propagation. The range of scale of turbulent eddy effective to the turbulent burning velocity might be changing during the flame propagation. Small flame kernel is wrinkled only by the small scales of turbulence. As the kernel continues to grow, it becomes progressively wrinkled by the larger length scales of turbulence. The turbulence that affects to flame kernel effectively was called "effective turbulence intensity" in this study. Energy spectrum of turbulence was obtained from PIV measurements. Effective turbulence intensity was evaluated quantitatively from energy spectrum of turbulence. Then relationship between turbulent burning velocity and effective turbulence intensity were investigated.
