Computational Study of the Propulsive Characteristics of a Shcramjet Engine

A shock-induced combustion ramjet is considered wherein gaseous hydrogen is injected via cantilevered ramp injectors located in a staggered manner on opposite walls of the internal duct of a mixed-compression inlet. The nonhomogeneous combustible mixture thus formed at the exit of the duct is then ignited through a shock generated by a wedge located on the lower wall of the duct. The products of the ensuing combustion process are then expanded in a specifically designed nozzle. The numerical simulation of the three-dimensional shcramjet flowfield at Mach 11 and an altitude of 34.5 km is performed by the Window Allocatable Resolver for Propulsion code, in which the multispecies Favre-averaged Navier-Stokes equations are closed by the k-w turbulence model and the Wilcox dilatational dissipation correction, to account for compressibility effects at high convective Mach number. The H 2 -air chemical reactions are modeled by a nine species, 20 reaction model based on that of Jachimowski. Magnitudes of the thrust, fuel specific impulse, and frictional forces on the entire shcramjet configuration are numerically determined. The moderate value of fuel specific impulse of 683 s is primarily due to the high equivalence ratio adopted.