Combustion Characteristics Experimental Study of Solid Hydrocarbon Propellant for Air-Turbo Rocket

The combustion characteristics of propellants heavily affect the performance of solid-propellant air-turbo rockets (SP-ATRs). In this study, an SP-ATR experimental combustion system was developed, and experimental studies were conducted on the primary and secondary combustion characteristics of two solid hydrocarbon fuel propellants. The results show that the solid hydrocarbon fuel-rich propellant, which is an ideal propellant for SP-ATRs, can play the dual role of driving the turbines and executing secondary combustion. The studies on the two candidate propellants show that CH01 has higher energy characteristics, and CH02 exhibits better performance in terms of the interior ballistic stability and ejection efficiency. For cold inflow conditions, when the fuel gas flow rate is at the optimum equivalence ratio, there are difficulties in secondary combustion. A combustion experiment with a variable gas flow rate was designed, and the upper limit of the excess air coefficient was obtained under the condition of cold inflow.