Abstract: In order to explore the feasibility and ablation behavior of the three-dimensional needled C/SiC in the hybrid rocket ramjet, the C/SiC composite nozzle was experimentally investigated. The results show that the three-dimensional needled C/SiC composite nozzle can work safely under the oxygen-rich combustion environment of the ramjet for long test duration. No obvious oxidation is observed in the entrance and divergent section of the nozzle. Thermochemical ablation is the dominated ablation mechanism for the nozzle throat. Thermochemical ablation and thermal-mechanical erosion were suggested as ablation mechanism for the convergent section of the nozzle. Convergent section is the weakest part of the nozzle. Hence for the safety and reliability of the nozzle, the thickness of the three-dimensional needled C/SiC composite in different positions of the nozzle should be optimally designed for different working conditions and ablation mechanisms. 

Key words: Ramjet; Nozzle; Ablation behavior

摘要： 为探索C/SiC喷管在固液冲压发动机上应用的可行性以及固液冲压发动机工作环境下的烧蚀行为,对冲压发动机针刺C/SiC复合材料喷管进行了研究。研究结果表明:针刺C/SiC复合材料喷管能够适应冲压发动机富氧、长时间的工作环境；C/SiC复合材料喷管入口段和扩张段存在轻微的氧化,喉部以热化学烧蚀为主,收敛段以热化学烧蚀和热机械侵蚀为主；收敛段为整个喷管的薄弱环节,应根据不同的工作条件和烧蚀机理,对C/SiC喷管的厚度进行分别设计。 

关键词: 冲压发动机;喷管;烧蚀行为 