沉积速率及其对喷管壁温影响的理论研究

固体火箭发动机喷管的沉积不仅影响发动机工作性能也影响喷管壁表面和壁内的温度随时间的变化规律,本文根据沉积过程的传热模型计算了三氧化二铝在固体火箭发动机喷管喉部的沉积速率,与实验结果相符合,并计算了在沉积过程中喷管壁内温度分布随时间的变化过程,数值计算表明,在沉积的初始阶段由于凝相粒子所释放的热量将增加向喷管壁内的传热,温度上升比没有沉积时要快,随着沉积层的加厚逐渐阻挡气相向喷管壁的传热,而使壁内的温度随时间的增加有一个峰,理论与实验结论一致。

STUDY OF DEPOSITION RATE AND INFLUENCE ON TEMPERATURE OF THE NOZZLE WALL

The deposition on the nozzle throat surface of solid propellant motor influences not only the engine performance, but also the wall temperature of the nozzle. Based on the heat transfer model for the deposition process the deposition rate can be calculated and agrees well with experimental results. The calculated temperature distribution in the nozzle wall and the deposition layer shows that during the initial deposition period the deposit enhances the heat transfer from the gas phase to the nozzle wall compared with the non-deposition situation. The temperature rising in the nozzle wall has a peak following to the existed deposit which inhibits the heat tranferred from the gas phase which agrees with the experimental conclusion.