燃气发生器条件下穿刺C/C复合材料喷管的烧蚀性能研究

研究了穿刺C/C复合材料喷管在酒精/氧气燃气发生器模拟的液体火箭发动机富氧燃气环境中的烧蚀性能, 分析了穿刺C/C复合材料的烧蚀机理及燃气参数对烧蚀性能的影响. 结果表明, 喷管喉部线烧蚀率为(0.055±0.029)mm/s, 质量烧蚀率为0.186kg/(m²·s). 喷管收敛段下游到喉部区域烧蚀最严重, 收敛段上游其次, 扩散段烧蚀最弱. 烧蚀过程是热化学烧蚀和气流冲刷综合作用的结果, 燃气温度和氧化性组分H₂O和CO₂含量决定穿刺C/C复合材料热化学烧蚀率, 压强和流速影响穿刺C/C复合材料的机械剥蚀.

Ablation Characteristic of the Pierced C/C Composite Nozzle in a Combustion Gas Generator

Ablation property of the pierced C/C composite nozzle was investigated via fire testing by a combustion gas generator which simulated oxy-rich combustion environments of the liquid rocket engine. Ablation mechanisms of the pierced C/C composite nozzle and effects of the combustion gas parameters were discussed. The results show that the linear ablation rate at the throat of the composite nozzle is 0.055±0.029mm/s, and the mass ablation rate is 0.186kg/(m² ·s). blation behavior of the pierced C/C composite nozzle is directly affected by the compositions, temperature, pressure and the velocity of combustion gases, which shows a non-uniform process. Ablation in the regions ranging from the downstream of the convergent section to the throat is the most severe. Ablation mechanisms of the pierced C/C composite nozzle are cooperation of thermo-chemical ablation and thermo-mechanical erosion. The former is primarily dependent on the combustion temperature and concentrations of H₂O and CO₂, while the latter is influenced by the pressure and velocity of the combustion gas.