固液火箭发动机燃烧流动与燃面退移规律研究

【作者】 陈灏；

【导师】 胡春波；

【作者基本信息】 西北工业大学 ， 航空宇航推进理论与工程， 2007， 硕士

【摘要】 固液火箭发动机在成本控制、安全性、可靠性，排气羽流信号特征、环境等方面的优良特性，越来越受到国内外航天专家的重视。由于氧化剂和固体燃料的组织燃烧方式不同，使得固液火箭发动机工作过程与固体、液体火箭发动机有很大的区别。本文开展了固体燃料热分解实验，建立了Arrhenius类型热分解关系式，在此基础上对固液火箭发动机内燃烧、流动与燃面退移速率进行了数值计算模拟。 开展了固液火箭发动机固体燃料的热分解实验，通过DSC方法与热平板导热技术分别测量了某固体燃料的热分解特性，确定其Arrhenius类型化学动力学参数，并进行了固体燃料热分解气体的收集、组分分析，为建立固液火箭发动机燃面退移速率的数值计算模型提供了实验数据。 建立了有关固液火箭发动机燃烧、流动与燃面退移速率的数值计算模型，并通过已有实验数据进行了数值计算结果准确性的验证。在此基础上分析了GOX／HTPB固液火箭发动机内燃烧、流动特性，燃烧主要集中在固体装药表面和发动机轴线之间的一个带状区域内，发动机轴线附近以及固体装药表面附近氧化剂和燃料热解气体混合程度较差，温度较低。 对采用液态氧化剂HNO₃80％+N₂O₄20％（质量比）和某型固体燃料（热分解产物主要是C₄H₆）组合的固液火箭发动机内燃烧、流动与燃面退移速率进行了数值模拟。分析了氧化剂质量流量和长径比变化对固液火箭发动机内温度，组分浓度等的分布情况及燃面退移沿轴线变化的规律，点火过程及不同时刻固体燃料型面退移状况。更多还原

【Abstract】 Remarkable advantage such as low costing, high security, high reliability, low exhaust plume signal characteristic and environment non-pollution, which does not belong to Solid Rocket Motor （SRM） or Liquid Rocket Engine （LRE）, advances astronautic experts to have much more interest in Hybrid Rocket Motor （HRM）. Because the combustion mode between oxidizer and solid fuel is in particular, HRM is different from SRM and LRE. This thesis successfully builds Arrhenius-type pyrolysis law of HRM solid fuel by carrying on an experiment research on pyrolysis behavior, and further presents numerical simulation phenomenon on combustion, flow and surface regression rate of HRM. The content of this thesis can be divided into three parts:This part develops pyrolysis behavior analysis of HRM solid fuel by two approaches: first, Differential Scanning Calorimetry （DSC）; second, hot-plate conductive heating, and completes gas collection of solid fuel pyrolysis. The experiment results of both Arrhenius-type kinemics parameters and qualitative and quantitative analysis on pyrolysis gas are determined for numerical calculation of solid fuel surface regression rate in HRM.A GOX/HTPB numerical model which presents combustion, flow and surface regression rate of HRM is well built and is proved to be high veracity in solid fuel surface regression rate by contrasting experiment data in second part. Based on above validation, some characteristics of HRM combustion and flow are spread out to such that. High temperature flame is mostly concentrated in strip zone between solid fuel surface and motor axis, and the extent of gas mixing is not good in the neighborhood of motor axis and solid fuel surface so that here temperature is a little lower.As to liquid oxidizer HNO₃80% + N₂O₄20% （mass ratio） and some solid fuel （pyrolysis gas is mainly C₄H₆）, the last part in detail describes numerical simulation process of HRM combustion, flow and surface regression rate. It analyzes the influence of oxidizer mass flux and length-radius ratio on HRM temperature filed and component concentration distributing, and demonstrates igniting and solid fuel surface regressing.更多还原