Comparison of combustion characteristics of four strut injectors with that of three strut injectors by numerically investigating doubly-dual cavity-based scramjet combustor

A numerical investigation has been conducted using 2D RANS (Reynolds Averaged Numerical Solution) equation and SST k- omega turbulence model in a cavity-based scramjet combustor with a doubly-dual cavity and hydrogenfuelled, to study the performance and combustion characteristics of three struts and four struts injection. Fluid flow characteristics of four-strut injectors were compared with that of three-strut injectors. The reason for better performance output from four strut injection is understood and discussed briefly. Compared with the three-strut injector configuration, the formation of recirculation regions and vortices are enhanced in the four-strut injector system affecting shock wave interactions (shock-shear, shock-shock layer). Due to increased levels of shock layer interaction, and lower presence of oxygen, there was a better mixing of the fuel which resulted in improvement in combustion when four strut injectors were introduced. The intensity of combustion also increased which is evident from static temperature plots.