Ramjet-Mode Operation in a Combined Cycle Engine Combustor

Abstract

A rocket-ramjet combined-cycle engine was tested in ramjet-mode. The combustor model had two rockets in the combustor section. They were used as an igniter in this operation mode. In the preliminary tests, the downstream combustion ramjet-mode was demonstrated with a 1.4-degree of divergent duct condition. In this study, the upstream and downstream combustion ramjet-mode operations were applied to the combined cycle engine model with large angle of divergent duct condition. In the case of upstream combustion ramjet-mode, the combustion condition at the exit of the combustor showed high combustion efficiency.

Research Activities of Advanced Propulsion Technology in JAXA

“…Effects of the position of fuel injection and the angle of the divergent section on pressure distribution, i.e., mixing and combustion processes, were investigated. 15 Figure 11 shows the experimental model.…”