Role of different cavity flame holders on the performance characteristics of supersonic combustor

Abstract The study’s primary goal was to assess the effects of different geometrical configurations of cavity flame holders on the performance characteristics of an H 2 -based scramjet combustor overall efficiency, focusing on mixing efficiency, combustion performance, and total pressure loss. Key findings indicate that incorporating a cavity into the combustor design leads to developing a robust recirculation zone within the cavity area. This recirculation zone is pivotal in enhancing fuel-air mixing and combustion efficiency, with cavity-based combustors showing an earlier onset of combustion and achieving peak combustion efficiencies around 90–95 %. The extent of the recirculation region is notably influenced by the proximity of the strut injector to the cavity’s length. This shock interaction can adversely affect scramjet combustor performance, especially at higher cavity angles ( α ) and specific geometric configurations, such as an L / D ratio of 4 and α = 30°. This advantage is critical, especially considering the compact length of the combustor, which is a desirable attribute in scramjet design.