氧浓度对锆粉点火燃烧特性的影响研究

Effects of Oxygen Concentration on Ignition and Combustion Characteristics of Zirconium Powder

关键词:  固体推进剂  推进剂添加剂  氧浓度  点火特性  燃烧特性  激光点火

摘要:

为探究氧浓度对锆粉点火燃烧特性的影响规律，利用激光点火、高速摄影仪、双色红外测温仪和光纤光谱仪等手段对锆粉的燃烧过程进行研究，获得了锆粉燃烧过程中的点火延迟时间、燃烧时间、燃烧强度和燃烧温度等参数。随后又利用XRD手段分析了燃烧产物的物相特征。通过实验发现：根据火焰形态可以将锆粉燃烧过程分为起燃、剧烈燃烧、平稳燃烧和火焰熄灭等四个阶段。氧浓度对锆粉的点火燃烧性能具有重要影响。C1~C4四种工况下锆粉的点火延迟时间分别为15ms，17.5ms，22.5ms和25ms；燃烧温度分别为1542℃，1520℃，1425℃和1405℃。因此增大氧浓度有利于缩短点火延迟时间和燃烧时间，提高燃烧温度和燃烧强度，改善锆粉的点火燃烧性能。氧浓度增大，火焰尺寸，火焰亮度和剧烈程度呈增大趋势。同时还发现锆粉在四种不同氧浓度下的反应产物主要为ZrO₂，未产生ZrN和ZrC等。

Abstract:

To study the effects of oxygen concentration on the ignition performance of zirconium powder, the combustion process of zirconium powder was observed by CO₂ laser ignition bench, high-speed camera, two-color infrared thermometer and fiber optic spectrometer. The ignition delay time, combustion time, combustion intensity and combustion temperature parameters during the combustion of zirconium powder were obtained. Subsequently, the phase characteristics of the combustion products were analyzed by XRD. It is known from the experimental results that the combustion process of zirconium powder can be divided into four stages: lighting, intense combustion, stable combustion and flame extinction according to the flame shape. The oxygen concentration has an important influence on the ignition and combustion performance of zirconium powder. The ignition delay times of zirconium powder in the four working conditions of C1~C4 are 15ms, 17.5ms, 22.5ms and 25ms, respectively. The combustion temperatures are 1542℃, 1520℃, 1425℃ and 1405℃, respectively. Therefore, increasing the oxygen concentration is beneficial to shorten the ignition delay time and combustion time, increase the combustion temperature and combustion intensity, and improve the ignition and combustion performance of the zirconium powder. As the oxygen concentration increases, the flame size, flame brightness and combustion intensity show an increasing trend. At the same time, it was found that the main phase of the combustion product of zirconium powder at four different oxygen concentrations is ZrO₂, and no phase such as ZrN and ZrC is produced.