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

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.