Figure 7: Twelve representative images illustrating the relative spatial combustion efficiency for a low-oxygenation flame during the initial one second after ignition, after the beginning of the combustion, from  sec (top left image) to  sec (bottom right image). In the black-and-white rendition, the dark lines inside the flames indicate ratio of about three between the amounts of carbon monoxide to that of dioxide. The inside region does not participate in an effective combustion, generating mostly carbon monoxide.