为了研究流化气体对粉末推进剂点火燃烧性能的提高作用,采用CO2激光点火器和光纤光谱仪相结合的实验方法,研究了不同气氛条件下Al粉的点火燃烧特性.采用光谱信号拟合测温法计算了Al粉在不同气氛环境中的点火温度.结果表明,常压环境下,粒径1μm的Al粉在N2O和空气氛围下的点火延迟时间分别为10ms和359ms,从点火成功过渡到全面燃烧的时间分别为829ms和1579ms,说明Al粉在N2O环境中点火阶段的表面异相反应速率与燃烧阶段的反应速率均快于在空气中;粉径1μm的Al粉在N2O和空气环境下的点火温度分别为1550~1650K和1450~1500K,两者相近,但都明显低于毫米级Al粉的点火温度(2300K),说明Al粉的点火温度受粒径影响较大.%To study the improving effect of fluidization gas on the performances of ignition and combustion for powder propellant, the characteristics of ignition and combustion for aluminum powder were investigated under different atmosphere conditions using the experimental method of CO2 laser igniter coupled with fiber optic spectrometer.The ignition temperature of aluminum powder under different atmospheres were calculated by measuring temperature method of fitting the spectral signal.The results show that the ignition delay of aluminum powder with the size of 1μm under N2O and air atmosphere is 10 and 359ms, respectively, and the transition time from successful ignition to full combustion is 829 and 1579ms, respectively, indicating that the heterogeneous reaction rate of aluminum surface in ignition stage and combustion stage is faster in N2O than in air.The ignition temperature of aluminum powder with the size of 1μm in N2O and air is 1550-1650 and 1450-1500K, respectively, which are almost the same, but they are obviously lower than the ignition temperature of 2300K of millimeter level aluminum powder, indicating that the particle size has an important effect on the ignition temperature of aluminum powder.
展开▼
