固体火箭超燃冲压发动机燃烧性能影响因素研究

Ground direct-connected experiments and numerical simulations were carried out to obtain the influence factors of the combustion performance of the solid rocket scramjet operating in cruise mode at flight Mach number 5.5. The effects of the injection mode of the fuel-rich gas, stages of the turbulence device and the expansion ratio of combustor on the performance of combustor were studied by numerical method. A combustor configuration with a vertical injection mode was found to be with a high combustion efficiency (≥90%). The results show that: (1) The vertical injection mode could enhance the mixing process of fuel-rich gas and air, and the combustion efficiency of particle phase was 25% higher than that of the central-strut with dual-rockets configuration. (2) The effects of different number of turbulence device stages on engine performance were compared. As thermal protection of turbulence devices and the complexity of engine structure were considered, the combustor with double stages turbulence devices was considered to be the best choice. The combustion efficiency of the particle phase in this combustor was 26% higher than that of the combustor with a single-stage turbulence device. (3) The effects of different combustor expansion ratios on engine performance were compared. The combustion efficiency of the particle phase was 95% when the expansion ratio of the combustor was 1.6. In conclusion, a combustor with a vertical injection mode, double-staged turbulence device and a combustor expansion ratio of 1.6 were optimized with high combustion efficiency.