解开高能固体推进系统的高效-初始化-基-终结聚丁燃烧的复杂性
Grace L Rizzo1, Souvick Biswas1, Dongwon Ka2
1Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, United States.
The journal of physical chemistry. A
|December 26, 2024
概括
在基终结聚乙烯 (HTPB) 燃料中的 (B) 颗粒因高效的能量转移而自发点燃. 这项研究揭示了.
科学领域:
- 材料科学 材料科学 材料科学
- 燃烧科学 燃烧科学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 基终结聚乙烯 (HTPB) 是用于固体火箭燃料的聚合物粘合剂.
- 将有能量的颗粒纳入HTPB可以提高燃料性能.
- 了解B/HTPB的点火和燃烧机制对于优化固体火箭燃料应用至关重要.
研究的目的:
- 为了研究嵌入在HTPB中的颗粒的点火和燃烧行为.
- 阐明和HTPB在点火过程中的不同作用.
- 分析B/HTPB燃烧中涉及的复杂氧化化学.
主要方法:
- 激光加热悬浮的B/HTPB和纯的HTPB粒子.
- 现场光谱诊断包括拉曼光谱,红外光谱和UV-Vis光谱.
- 时间分辨率的高速光学和红外成像.
主要成果:
- 在空气中观察到B/HTPB的自发点火,与纯HTPB不同.
- 确定了两阶段的点火过程:初始点火,随后是HTPB燃烧.
- 由于的热容量较低,观察到从HTPB到颗粒的高效热能转移.
- 检测到氧化物 (BO,BO2) 作为关键中间体,触发HTPB分解.
- 甲醇和甲基乙烯乙等部分氧化产品的形成表明复杂的氧化途径.
结论:
- 颗粒通过吸收和转移激光能量,作为B/HTPB固体燃料中的点火触发器.
- 点火释放的能量驱动HTPB粘合剂的随后燃烧.
- 复杂的氧化化学涉及氧化物导致各种燃烧产品,为先进的固体火箭燃料设计提供了洞察力.
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