DUCTED ROCKETS FOR SPACEPLANES EFFECTS OF INJECTOR ON C* COMBUSTION EFFICIENCY

摘要

Spaceplanes like the Space Shuttle land without propulsion systems after re-entering. The landing area of spaceplanes is limited by the re-entry point. The re-entry area can be expanded by using propulsion systems. We selected ducted rockets for propulsion system of spaceplanes used after re-entering. When ducted rockets operate in high air-fuel ratio, the fuel rich hot gas is cooled down by the amount of air. The temperature in the secondary combustor decreases and the combustion efficiency reduces. To burn the fuel rich hot gas and the ram air easily, we set the multi-hole gas injector, and the fuel rich hot gas inject axially and radially. The effects of the multi-hole gas injector on the combustion efficiency of the secondary combustor were obtained with the direct connected pipe ducted rocket. As a result, combustion efficiency of C* with the multi-hole gas injector is 5 - 10% higher than that with the single hole nozzle injector. It is considered that the multi-hole gas injector makes a high temperature region forward in the secondary combustor, and mixed gas is able to burn easily.