流量脉动对针栓式喷嘴雾化特性影响的仿真分析  

Simulation analysis on the influence of flow pulsation on the atomization characteristics of a pintle injector

作　　者：谢远 聂万胜 高玉超 仝毅恒 XIE Yuan;NIE Wansheng;GAO Yuchao;TONG Yiheng(Department of Aerospace 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1期54-64,共11页Journal of Rocket Propulsion

基　　金：国家自然科学基金(12002386)。

摘　　要：针栓式喷嘴在变推力液体火箭中有重要应用。使用连续相到离散相方法和基于树形数据结构的自适应算法研究了气液针栓式喷嘴的雾化破碎过程,重点关注了液体流量脉动的影响。通过施加周期性变化的质量流量入口边界来模拟上游流量脉动下的雾化过程,对比了有无流量脉动条件下的雾化特性,研究了脉动频率对针栓式喷嘴雾化特性的影响。结果表明:当液体流量不变时,在气体的撞击作用下,液膜上剥落出较长的液丝,长液丝二次破碎为小液丝和大量液滴,破碎距离较长,液膜破碎过程比较有序;当流量脉动幅值为0.15,脉动频率的范围为500~3000 Hz时,液膜破碎距离会缩短,液膜会形成明显的环状表面波,破碎后在环形液丝周围出现液滴聚集现象,雾化锥角受脉动频率影响较小;脉动频率会显著降低液滴的粒径,当频率较高(3000 Hz)时,可能会产生数目较少的极大液滴粒径;液体流量脉动会使得液滴分布出现局部聚集现象,喷雾形态出现明显的“鼓包”结构。Pintle injectors have important application in variable thrust liquid rockets.The continuous phase to discrete phase method and adaptive algorithm based on tree data structure were used to study the atomization and crushing process of a gas-liquid pintle injector,with emphasis on the effect of liquid flow pulsation.The atomization process under upstream flow pulsation was simulated by applying periodically varying mass flow inlet boundary,and the atomization characteristics with or without flow pulsation were compared.The influence of pulsation frequency on the atomization of the pintle injector was studied.The results show that when the liquid mass flow was constant,the long liquid filaments are separated from the liquid film under the impact of gas flow,and the long liquid filaments are broken into small liquid filaments and a large number of droplets.The broken distance is long,and the liquid film breaking process is orderly.When the flow pulsation amplitude was 0.15 and the pulsation frequency ranges from 500 Hz to 3000 Hz,the crushing distance is shortened,the liquid film forms an obvious annular surface wave,and droplets gather around the annular liquid filament after crushing,and the atomization cone angle is less affected by the pulsation frequency.Pulsation frequencies significantly reduce droplet sizes,and at high frequencies(3000 Hz),a small number of large droplet may be produced.The liquid flow fluctuation makes the droplet distribution appear local aggregation phenomenon,and the spray shape appears obvious“bulge”structure.

关 键 词：气液针栓式喷嘴 连续相 离散相 数值模拟 流量脉动 雾化特性 

分 类 号：V434[航空宇航科学与技术—航空宇航推进理论与工程]