Criteria for flame holding in H2-fueled scramjet engines

Although self-sustaining combustion has often been termed auto ignition in studies on scramjet combustors, it should be interpreted as a flame-holding phenomenon rather than ignition. Criteria for flame holding in H 2 -fueled scramjet engines have been discussed by approximating the recirculation zone in the combustor with a perfectly stirred reactor. The influence of mass flow rates and reactor volumes on flame holding can be summarized by a critical reaction time in the recirculation zone. It was found that the reaction time was proportional to pressure, with P −13 for H 2 reactions, and the recirculation zone should be occupied with reactants having equivalence ratios in the range 0.4