推进技术
推進技術
추진기술
JOURNAL OF PROPULSION TECHNOLOGY
2015年
4期
608-613
,共6页
郑刚%聂万胜%何博%薛诚尤
鄭剛%聶萬勝%何博%薛誠尤
정강%섭만성%하박%설성우
撞击式喷嘴%撞击角%雾化特性%CLSVOF%数值仿真
撞擊式噴嘴%撞擊角%霧化特性%CLSVOF%數值倣真
당격식분취%당격각%무화특성%CLSVOF%수치방진
Impinging jets injector%Impingement angle%Atomization characteristics%CLSVOF%Numerical investigation
为了研究液体火箭发动机中撞击式喷嘴的雾化问题,采用CLSVOF(Coupled Level-Set and Volume-of-Fluid Method )方法对撞击式喷嘴的雾化过程进行了数值仿真模拟,重点考察了撞击角对撞击式喷嘴雾化特性的影响。结果表明,通过CLSVOF方法能对射流撞击雾化形态进行较好的捕捉;分析整个雾化区域的液相分布,将射流撞击雾化过程中的液相分布大致分为三个区域:撞击前两股独立射流区域、撞击后形成的液膜区域、液膜破碎后液丝和液滴的生成区域;射流撞击雾化除了气液界面上速度差引起的不稳定之外,还存在由射流湍流或撞击波引起的其它不稳定因素;液膜破碎长度随撞击角的增大而减小,液膜表面上的表面波幅值及液膜破碎程度则随撞击角的增大而增大;射流撞击在撞击点位置处所形成的速度差对液膜的破碎和液膜上表面波幅值的大小起到了关键作用。
為瞭研究液體火箭髮動機中撞擊式噴嘴的霧化問題,採用CLSVOF(Coupled Level-Set and Volume-of-Fluid Method )方法對撞擊式噴嘴的霧化過程進行瞭數值倣真模擬,重點攷察瞭撞擊角對撞擊式噴嘴霧化特性的影響。結果錶明,通過CLSVOF方法能對射流撞擊霧化形態進行較好的捕捉;分析整箇霧化區域的液相分佈,將射流撞擊霧化過程中的液相分佈大緻分為三箇區域:撞擊前兩股獨立射流區域、撞擊後形成的液膜區域、液膜破碎後液絲和液滴的生成區域;射流撞擊霧化除瞭氣液界麵上速度差引起的不穩定之外,還存在由射流湍流或撞擊波引起的其它不穩定因素;液膜破碎長度隨撞擊角的增大而減小,液膜錶麵上的錶麵波幅值及液膜破碎程度則隨撞擊角的增大而增大;射流撞擊在撞擊點位置處所形成的速度差對液膜的破碎和液膜上錶麵波幅值的大小起到瞭關鍵作用。
위료연구액체화전발동궤중당격식분취적무화문제,채용CLSVOF(Coupled Level-Set and Volume-of-Fluid Method )방법대당격식분취적무화과정진행료수치방진모의,중점고찰료당격각대당격식분취무화특성적영향。결과표명,통과CLSVOF방법능대사류당격무화형태진행교호적포착;분석정개무화구역적액상분포,장사류당격무화과정중적액상분포대치분위삼개구역:당격전량고독립사류구역、당격후형성적액막구역、액막파쇄후액사화액적적생성구역;사류당격무화제료기액계면상속도차인기적불은정지외,환존재유사류단류혹당격파인기적기타불은정인소;액막파쇄장도수당격각적증대이감소,액막표면상적표면파폭치급액막파쇄정도칙수당격각적증대이증대;사류당격재당격점위치처소형성적속도차대액막적파쇄화액막상표면파폭치적대소기도료관건작용。
Aiming at elucidating the detailed atomization process of the impinging-jet injector in liquid rock?et motor and the relationship between impingement angle and atomization characteristics of liquid sheet formed by the injector,numerical investigation of atomization characteristics of impinging jets injector is conducted based on the CLSVOF(Coupled Level-Set and Volume-of-Fluid Method)method. The study is focused on the effects of impingement angle on the atomization characteristics,and the simulation results are compared with the theoretic results. The simulation results show that the atomization characteristics of the liquid sheet formed by the impinging jets can be effectively captured by the CLSVOF method. By studying the liquid distribution of the atom?ization region,the liquid distribution in the atomization process can be divided into three regions:the separated jets region before the jets impact,the liquid sheet region after the jets impact and the formation of ligaments and droplets region. The present numerical results also show that the atomization process is affected not only by the in?stability caused by velocity difference on the gas-liquid interface,but also other factors such as turbulence inten?sity and impact wave. The breakup length of liquid sheet decreases with the increasing impingement angle ,the amplitude of surface wave on the liquid sheet and the breakup intensity of liquid sheet increase with the increas?ing impingement angle. The velocity difference at the location of impact point formed by the impinging jets plays a key role in the breakup of liquid sheet and formation of surface wave.