不同氧含量气氛下AlH3激光点火燃烧特性研究

Study on Laser Ignition and Combustion Characteristicsof Aluminum Hydride under Different OxygenContent Atmospheres

关键词:  AlH₃  点火  燃烧  氧含量  激光

Key words:  Aluminum hydride  Ignition  Combustion  Oxygen content  Laser

摘要:

三氢化铝（AlH₃）作为一种新型含能材料，可显著提升固体推进剂的比冲，具有广阔的发展前景。为了填补国内对AlH₃基础研究的空白，利用激光点火实验台对不同氧含量气氛下的AlH₃进行点火燃烧实验，采用光纤光谱仪、高速相机、双色高温计监测样品点火燃烧过程中的火焰形貌、温度变化、光谱数据等，并对燃烧残留物进行理化特性分析。结果显示，AlH₃在燃烧过程中存在火焰脱离样品的现象。且随着气氛中氧含量的提高，燃烧强度增大，最高温度呈现增大的趋势，由1025.5℃增加到1350.0℃，点火延迟时间缩短，由22ms下降至4ms，燃烧时间呈现先延长后缩短的趋势。高氧含量气氛下与低氧含量气氛下的燃烧残留物形态和成分有很大不同。反应气氛中氧含量的提高可以有效促进AlH₃的点火燃烧性能。

Abstract:

As a new type of energetic material, aluminum hydride can significantly increase the specific impulse of solid propellants and has a broad development prospect. In order to fill the gap in the domestic research on aluminum hydride, the ignition and combustion experiment of aluminum hydride under different oxygen content atmospheres was carried out by using a laser ignition experimental bench. A fiber optic spectrometer, a high-speed camera and a two-color pyrometer were used to monitor the flame morphology, temperature changes and spectral data of the sample during ignition and combustion. Physical and chemical properties of combustion residues were analyzed. The results show that there is a phenomenon that the flame escapes from the sample during combustion. As the oxygen content in the atmosphere increases, the combustion strength increases, the maximum temperature increases from 1025.5℃ to 1350.0℃, the ignition delay time decreases from 22ms to 4ms, and the burning time first increases and then decreases. The morphology and composition of combustion residues in a high oxygen content atmosphere are very different from those in a low oxygen content atmosphere. The increase of oxygen content in the atmosphere can effectively promote the ignition and combustion of aluminum hydride.