Structure of a split gas flame

An experimental study of the effect of the burner exit velocity profile on the liftoff and reattachment characteristics of a gas jet flame is presented. With a set of tubes attached to a contoured nozzle, flat and rounded velocity profiles are generated at the burner mouth. With flat profiles flames liftoff at the burner mouth itself, whereas with rounded profiles extinction begins at higher levels and leads to the formation of split flames. The measured temperature, dynamic head, and concentration profiles at the extinction regions are presented in conjunction with schlieren photographs to discuss the effects of flow structure on the flame stability characteristics.