Abstract
We address in this paper the problem of pocket formation in turbulent premixed flames. Pockets of unburnt gases inside the burnt gases, or of burnt gases inside unburnt gases have been observed in experiments, usually in tomographic cuts of a three-dimensional flame. We study here two effects (range of length scales and different time correlations) controlling the number and type of pockets created, on the basis of a two-dimensional numerical study of the thermal-diffusive model subjected to an external turbulent forcing (i.e. we neglect the retroaction of the flame on the flow field).