摘要
大过载下固体火箭燃烧与流动状态的剧烈变化会导致内弹道出现异常,严重时可能会引起发动机点火失败。为研究横向过载时点火内弹道特性,建立囊括流场惯性过载效应、过载燃烧效应和侵蚀燃烧效应的点火模型。对不同横向过载下燃烧室压力和侵蚀与过载效应燃速增速占比进行计算,并给出了推进剂火焰传播速度与升压速率的关系。结果表明:正向过载下压力峰值增加,负向过载下压力峰值降低;正向过载下,推进剂前段主要由过载效应影响,后段主要由侵蚀效应影响;正向过载加剧下游侵蚀效应,而负向过载对推进剂的燃烧起削弱作用,但程度较弱、持续时间较短;火焰传播速度峰值时刻、推进剂表面首次全部点燃时刻和升压速率峰值点时刻几乎一致,工程上可以用实验中获得的升压速率分析推进剂表面燃烧状况。
The high acceleration is found to alter the internal ballistic performance and induce ignition abnormalities by changing the internal flow and combustion state in the rocket chamber.To demonstrate the mechanism of interior ballistics as the results of acceleration loads imposed,the modes of the acceleration field effect,acceleration combustion effect,and erosion combustion characteristics are developed and first taken into in a new ignition model.The transient pressure in combustion chamber and the proportion of erosion and acceleration effects versus time are obtained.The relationship between propellant flame propagation speed and pressure rise rate is proposed.The results show that the peak-pressure is increased under the condition of positive acceleration and weakened under the condition of negative acceleration.Under the condition of positive acceleration,the front section of propellant is mainly affected by the acceleration-combustion,and the rear section is mainly affected by the erosion-combustion.By intensifying upstream combustion,the downstream erosion effect is aggravated by the positive acceleration.The negative acceleration is found with a less weakening effect on the combustion of propellant in the rocket,both in magnitude and time duration.The moment of peak of flame-spread velocity is almost identical to the moment of ignition of the entire propellant grain and the peak of pressure-rate.Therefore,the pressure-rise rate of the pressure data obtained in the experiment can be suggested to analyze the surface combustion of propellant.
作者
官典
李世鹏
刘筑
王宁飞
GUAN Dian;LI Shipeng;LIU Zhu;WANG Ningfei(School of Aerospace Engineering, Beijing Institute of Technology, Beijing 100081, China;Science and Technology on Space Physics Laboratory, China Academy of Launch Vehicle Technology, Beijing 100076, China)
出处
《兵工学报》
EI
CAS
CSCD
北大核心
2021年第9期1877-1887,共11页
Acta Armamentarii
基金
军队科研项目(2019年)。
关键词
固体火箭发动机
推进剂
横向过载
点火建压
数值计算
solid rocket motor
propellant
lateral acceleration
ignition interval
numerical simulation
