Abstract
Direct numerical simulations of ignition and propagating of hydrogen-air premixed flame in two-dimensional homogeneous isotropic turbulence are conducted to investigate the effects of turbulence and equivalent ratio on ignition and propagation process. In the ignition process, eddies stretch the high temperature region and disturb its evolution. The influence of equivalent ratio is weak for the production of intermediates which are needed for ignition. In the propagation process, strong eddies prevent propagating of the flame, and the flame propagates along the edge of eddies. For stoicheiometric condition, the strong eddies near the flame kernel transport the flame into the burned gas and the transported flame shows high heat release rate. However, for lean conditions, the beat release rate is independent of the flame geometry and shows relatively high value.
