| Performance of hydrocarbon/air mixing in the inlet of a shock-induced combustion ramjet is investigated. The inlet is designed for Mach 8 vehicle flying at 1400psf dynamic pressure path and 28.6 Km altitude. The objective is to evaluate the impact of the inlet and fuel parameters on mixing efficiency. Three-dimensional flowfield analysis is undertaken by the Window Allocatable Resolver for Propulsion code, a finite difference solver using Yee-Roe limiting scheme. The multi-species Favre averaged Navier-Stokes equations are solved and closed by Wilcox k -- o turbulence model with dilatational dissipation correction. The results indicate that 0.85 mixing efficiency can be achieved without the risk of premature ignition. Inlet angle and fuel tank stagnation temperature are found to have a strong impact on mixing efficiency. Methane is shown to have mixing advantages over kerosene and hydrogen due to its lighter molecular weight and slow reactive nature. |
