平面超声速引射器内部流动的大涡模拟  

Large Eddy Simulation of Flow in a Plane Supersonic Ejector

作　　者：许常悦[1] 周涛[1] 王从磊[1] 

机构地区：[1]南京航空航天大学航空宇航学院,江苏南京210016

出　　处：《航空学报》2014年第8期2136-2143,共8页Acta Aeronautica et Astronautica Sinica

基　　金：国家自然科学基金(11202100);江苏省自然科学基金(BK2011723);中央高校基本科研业务费专项资金(NS2012032);江苏省博士后科研资助计划(0902001C);江苏高校优势学科建设工程资助项目~~

摘　　要：采用大涡模拟(LES)方法对平面超声速引射器的内部流动进行了数值研究。为了验证LES方法的可靠性,对计算结果和实验数据进行了定量对比,对比的物理量有速度和温度剖面。结果表明当前计算结果和实验数据吻合得较好,这说明LES方法能够有效地研究此类问题。引射器主射流的失稳过程与自由射流的失稳过程相同,分为增长、失稳和混合3个阶段。Lamb矢量散度的分布表明,混合室内部的混合过程被限制在狭小的带状区域。混合室内压力信号的功率谱分析表明,主射流的失稳主导着混合室内部流体的混合过程,其特征St数约为0.27。The flow in a plane supersonic ejector is investigated numerically using a large eddy simulation （LES） technique.In order to validate the reliability of LES method,quantitative comparisons of the calculated result with experimental data are made including the velocity and temperature profiles.They show that the present computational results agree well with the experimental data,which indicates that the LES method can be used to study this problem.The instability processes of the primary jet in the ejector are the same as those of the free jet,which can be divided into three different stages,i.e.,shear layer growth,instability and mixing.Distributions of the Lamb vector divergence indicate that the mixing process is restricted in a narrow zonal-area.Power spectral density analysis of pressure signals in the mixing section shows that the flow mixing process is dominated by the primary jet instability,and the characteristic Strouhal number is approximately 0.27.

关 键 词：可压缩流动 引射器 射流 大涡模拟 湍流 

分 类 号：V211.3[航空宇航科学与技术—航空宇航推进理论与工程]