固体推进剂燃烧颗粒粒径的在线测量

Online Size Measurement of Burning Particles of Solid Propellants

提出了一种基于Fraunhofer衍射理论的燃烧颗粒粒径在线测量方法。根据固体推进剂药条燃烧火焰辐射光谱特性,选取450 nm蓝紫光激光器为光源,采用450 nm滤波探测方式消除固体推进剂燃烧的自发光辐射影响,搭建了固体推进剂药条燃烧颗粒粒径的在线测量系统。并利用10.9μm标准颗粒、160μm标准颗粒、及混合标准颗粒系对该系统开展粒径测量验证。燃烧实验的结果表明,固体推进剂药条燃烧颗粒的粒径约为10μm和160μm,呈双峰分布特征,数目分布主要集中在160μm左右,随着药条燃烧时间增加,10μm附近颗粒数量增多,160μm附近颗粒数量减少。对于同一燃速下的固体推进剂,初始测量高度越高,燃烧颗粒的粒径越小。在初始测量高度相同时,不同燃速下燃烧颗粒的平均粒径相差不大。这些结果为固体推进剂燃烧过程研究提供了参考。

This study presents an online size measurement method for burning particles based on the Fraunhofer diffraction theory.According to the spectral characteristics of medicinal strip combustion flame radiation in solid propellants,a blue-violet laser with a wavelength of 450 nm is used as the light source,and a filtering detection method with a passing band of 450 nm is used to eliminate self-luminous radiation influence of solid propellant combustion.An online measurement system for measuring the particle sizes of burning particles in solid propellants is developed.For calibrating this measurement system,standard particles with size of 10。9μm,160μm,and mixed standard particles are measured.The combustion experimental results show that the size of burning particles in solid propellants are approximately 10μm and 160μm,presenting a bimodal distribution,and the number distribution is mainly concentrated around 160μm.As the combustion time increases,the number of particles with a size of 10μm increases and the number of particles with a size of around 160μm decreases.For a solid propellant with same burning rate,the higher the initial measurement height,the smaller the combustion particle size.For measurements with same initial heights,there is no considerable difference in the average particle size of burning particles at different burning rates.This study provides a reference for the investigation of the solid propellant combustion process.