一种燃速可调的光控固体推进剂燃烧特性

Combustion Characteristics of the Laser⁃controlled Solid Propellant with Adjustable Burning Rate

为了研究光控固体推进剂在激光辐照下的可控燃烧特性以及推力性能,采用高速摄影、高精度压力传感器、R型热电偶以及微推力测试平台等装置分别获取了不同激光功率密度下,光控固体推进剂的燃速、点火延迟时间、燃烧室压强、燃烧火焰温度以及微推力等性能参数。结果表明:光控固体推进剂的燃速与燃烧室压强均随激光功率密度的增加而线性升高,与之相反,其点火延迟时间随激光功率密度的增加呈下降趋势。结合热电偶测温曲线,发现光控固体推进剂的燃烧过程主要分为五个区域:预热区、凝聚相区、三相区、气相区以及火焰区,与此同时,在1.343 W·mm^(-2)的激光功率密度下,推进剂的燃烧火焰温度为1202.3℃。光控固体推进剂燃烧状态对于激光功率密度的依赖性对于实现推力的精确控制具有重要意义,通过改变激光功率密度的大小,成功实现了光控固体推进剂的推力控制;随着激光功率密度由0.344 W·mm^(-2)增加到1.343 W·mm^(-2),光控固体推进剂的推力由1.58 mN上升至2.28 mN。

A high⁃speed camera,a high⁃precision pressure sensor,an R⁃type thermocouple and a micro⁃thrust test bench has been used to investigate the controllable combustion behaviors and thrust performance of the laser⁃controlled solid propellant(LCSP)under laser irradiation.The burning rate,ignition delay time,chamber pressure,combustion flame temperature and mi⁃cro⁃thrust under different laser power densities were obtained.The results showed that the burning rate and chamber pressure in⁃creased linearly,while the ignition delay time decreased with increasing laser power density.Combining the thermocouple tem⁃perature curves,it was concluded that the combustion process of LCSP might be divided into five zones:pre⁃heating zone,con⁃densed phase zone,triple zone,gas phase zone and flame zone.Meanwhile,the combustion flame temperature of the LCSP was 1202.3℃under the laser power density of 1.343 W·mm^(-2).Dependence of the combustion status on laser power density makes sense to realize the accurate adjustment of micro⁃thrust.In the experiment,the thrust control of LCSP is successfully real⁃ized by changing the laser power density.As the laser power density increased from 0.344 W·mm⁃2 to 1.343 W·mm^(-2),thrust of the LCSP increased from 1.58 mN to 2.28 mN.