环境压力对气液针栓式喷嘴雾化特性的影响  

Effect of ambient pressure on the atomization characteristics of gas-liquid pintle injector

作　　者：谢远 聂万胜 高玉超 苏凌宇 仝毅恒 XIE Yuan;NIE Wansheng;GAO Yuchao;SU Lingyu;TONG Yiheng(Department of Astronautical Science and Technology,Aerospace Engineering University,Beijing 101416,China)

机构地区：[1]航天工程大学宇航科学与技术系,北京101416

出　　处：《火箭推进》2023年第3期15-25,共11页Journal of Rocket Propulsion

基　　金：国家自然科学基金项目(12002386)。

摘　　要：气液针栓式喷嘴在变推力液体火箭中有重要应用。采取实验与数值计算结合的方法系统研究了不同环境压力下的针栓式喷嘴的液膜破碎过程、喷雾锥角、回流区分布、压力和液滴粒径分布等雾化特性,揭示了环境压力影响液膜破碎的3个因素:气流冲击、环境气体密度和环境压力对液膜挤压作用。结果表明:喷雾锥角会随环境压力增加而增大,但该趋势会随压力的增加而逐渐放缓。喷雾整体形态呈现锥形,喷雾中心区域存在低压回流区,回流区的液滴数目较少,但液滴粒径比较均匀。液滴主要分布在气液作用面,下游的液滴粒径较大,外部的液滴粒径比内部的大。液体火箭在启动的瞬间,燃烧室压力变化剧烈,可能导致喷雾锥角发生大幅变化,引起推进剂空间分布不均匀,对燃烧性能产生影响,因此要避免或减小较差雾化效果的燃烧室设计压力区间。Gas-liquid pintle injector has important application in variable thrust liquid rocket.In order to study the influence of ambient pressure on the atomization characteristics of gas-liquid pintle injector,the atomization characteristics of the injector under different ambient pressures,such as the liquid film breaking process,spray cone angle,reflux zone distribution,pressure distribution and droplet size,were systematically studied by experiments and numerical computation.Three factors affecting liquid film breakage were revealed:airflow impact,ambient gas density and the effect of ambient pressure on liquid film extrusion.The results show that the spray cone angle increases with the increase of ambient pressure,but the increasing trend of spray cone angle decreases gradually.The overall shape of the spray is conical,and there is a low-pressure reflux area in the center of the spray.The number of droplets in the reflux area is small,but the particle size of droplets is relatively uniform.The droplets are mainly distributed on the gas-liquid interaction surface,and the particle size of the droplets downstream is larger,while the particle size of the droplets outside is larger than that of the droplets inside.At the moment when liquid rocket starts,the combustor pressure changes dramatically,which may lead to a large change in spray cone angle,resulting in uneven spatial distribution of propellant and affecting combustion performance.Therefore,it is necessary to avoid or reduce the design pressure interval of combustor with poor atomization.

关 键 词：气液针栓式喷嘴 环境压力 喷雾锥角 回流区 液滴粒径 

分 类 号：V434[航空宇航科学与技术—航空宇航推进理论与工程]