基于不稳定性理论的离心喷嘴液雾SMD半理论预测  

Semiempirical prediction of Sauter mean diameter for pressure swirlatomizer based on instability theory

作　　者：高昭 刘玉英[1] 张权 黄勇[1] 王东辉 GAO Zhao;LIU Yuying;ZHANG Quan;HUANG Yong;WANG Donghui(School of Energy and Power Engineering,Beihang University,Beijing 100191,China)

机构地区：[1]北京航空航天大学能源与动力工程学院,北京100191

出　　处：《航空动力学报》2024年第9期245-255,共11页Journal of Aerospace Power

基　　金：国家科技重大专项(J2019-Ⅲ-0016-0060)。

摘　　要：基于液膜雾化的不稳定性理论,同时考虑离心喷嘴锥形液膜气液相互作用过程中开尔文-亥姆霍兹(K-H)不稳定性和瑞利-泰勒(R-T)不稳定性对液膜破碎的影响,建立了离心喷嘴液雾索太尔平均直径(SMD)半理论预测模型,并在燃油温度240~300 K、燃油压力0.5~3 MPa条件下开展了离心喷嘴燃油雾化全息试验和激光多普勒粒子分析仪(PDPA)测试验证试验。研究表明:液膜表面同时存在流向波和周向波,燃油压力和燃油温度的降低,均会抑制液膜表面不稳定性的发展,使得液雾SMD增大,且相较于K-H不稳定性,燃油压力变化对R-T不稳定性的影响更为显著;模型可实现对变物性、结构和工况离心喷嘴液雾SMD的良好预测,最大预测误差在±15%左右,对离心喷嘴的雾化性能预测和结构优化设计具有一定的工程应用价值。Based on the liquid atomization instability theory,a semiempirical model was established to predict the Sauter mean diameter(SMD)of pressure swirl atomizers,considering the Kelvin-Helmholtz(K-H)instability and Rayleigh-Taylor(R-T)instability generated by the interactions between air and liquid film.The experiments were also conducted using phase Doppler particle analyzer(PDPA)technique and digital off-axis holography with liquid temperature ranging from 240—300 K and liquid pressure ranging from 0.5—3 MPa.The results showed that:there were circumferential waves and axial waves on the surface of liquid sheet.With the decrease of liquid pressure and liquid temperature,the instability of liquid film was inhibited,which led to the increase of the SMD.Compared with the K-H instability,the effect of the liquid pressure on R-T instability was more significant;the effects of liquid physical properties,geometrical structures and operating conditions were included in the semiempirical correlation.The predictions showed good agreement with the experimental results,and the maximum uncertainty of the semiempirical correlation to predict the SMD was about±15%for the available experimental data,making it valuable for the prediction of atomization performance and the optimization of the structure of pressure swirl atomizers.

关 键 词：离心喷嘴 锥形液膜 不稳定性理论 索太尔平均直径 预测模型 

分 类 号：V231.2[航空宇航科学与技术—航空宇航推进理论与工程]