Combustor/Inlet Interactions and Modeling of Hypersonic Dual Combustor Ramjet Engines

摘要

The purpose of this research has been to experimentally and analytically describe the inlet/combustor/exit nozzle flowfields in hypersonic DCR (Dual combustion Ramjet) engines. The experimental effort to date describes, in part, the flow characteristics in the isolator duct that conducts air supersonically from the external flowfield of the hypersonic air inlet to the supersonic combustor. This description includes the mean flow properties, the turbulent fluctuation flow properties, the boundary layer growth and the simulated precombustion compression field for an initial Mach 2.4 flow in a 20-in. long annular duct with inner and outer radii of 3.125 and 4.2 in., respectively. The analytical effort includes models that describe: (1) the recirculation region at the DCR gas generator base created by a surrounding supersonic jet; (2) the mixing and burning processes in the DCR supersonic combustor; (3) the supersonic combustor boundary layer; and (4) the nozzle flow. The models include such enhancements as finite rate, multiple species chemistry, the solution of the full Navier-Stokes equations for axisymmetric flow and energy transfer due to mass diffusion.