The implications of dual cavity location in a strut-mounted scramjet combustor

The effect of dual cavity locations with strut injection configuration in a supersonic flow under reacting con-ditions has been numerically evaluated. The simulation is performed by adopting a two-dimensional planar model utilizing RANS technique by applying SST k-& omega; turbulence model with single-step reaction chemistry. The top wall cavity is fixed at strut downstream, whereas the bottom wall cavity is mounted at four locations to analyze the shock wave pattern and their associations with shear layer mixing features. The flow pattern, static pressure and temperature distributions, and performance analysis throughout the combustor length for the dual cavity designs associated with the results of the DLR scramjet are investigated. Comparing the dual cavity structure with the baseline model results in a 25% reduction in combustion chamber length and complete combustion, while the total pressure drop increases by 20% due to the additional shock waves from the cavities. Nevertheless, the pressure drop for the cavity cases is less than 2% due to the replacement. Additionally, the combustion zone prolongs in the lateral direction as the dual cavities are located close to the strut injector.