超声速中等欠膨胀冲击射流的涡声关系研究  

RESEARCH ON RELATIONSHIP BETWEEN VORTEX AND SOUND OF MODERATELY UNDER-EXPANDED SUPERSONIC IMPINGING JET

作　　者：崔新光[1] 姚朝晖[1] 张锡文[1] 

机构地区：[1]清华大学航天航空学院,北京100084

出　　处：《力学学报》2009年第2期169-176,共8页Chinese Journal of Theoretical and Applied Mechanics

基　　金：国家自然科学基金资助项目(10572074)~~

摘　　要：使用大涡模拟方法对冲击面为平面的超声速中等欠膨胀冲击射流进行了数值模拟.利用三阶迎风和四阶对称紧致格式对无量纲化轴对称可压缩滤波N-S方程进行空间离散,时间上推进采用的是三阶精度的TVD型Rugge-Kutta法.通过与经典的冲击射流实验比较,证实了程序的可靠性.数值模拟得到了流场中不同尺度的涡结构和激波结构,观察到了上行声波和反射波以及流场中不同位置的声源,分析了冲击区剪切层附近区域的压强和涡旋转强度变化的频率、冲击平板上的压强变化频率以及射流剪切层中不同位置的涡合并出现的频率,发现冲击区剪切层附近区域的压强和涡强度变化以及射流剪切层中的涡合并现象和离散频率的冲击单音有重要关联.This paper studies moderately under-expanded supersonic jet impinging on flat plate by using largeeddy simulation. A third-order upwind compact difference and a fourth-order symmetric compact scheme are employed to discretize the nondimensional axisymmetric compressible Favre-filtered Navier-Stokes equations in space, while the third-order Runge-Kutta method with the TVD property is adopted to deal with the temporal discretization. The numerical results are first validated with the experimental data of the classic impinging jet. The shock wave and vortex structure with different scales in the flowfield, the wave traveling upon and reflecting back, and sound sources in different locations are acquired in the simulation. The frequencies of the change of pressure and swirling strength in the shear layer at different position, pressure change on the impinging plate, and the vortex merging in the jet shear layer are obtained with Fourier analysis. We found that the change of pressure and swirling strength in the shear layer, pressure change on the impinging plate, and vortex merging in the jet shear layer are associated with impinging tone.

关 键 词：超声速冲击射流 紧致格式 大涡模拟 涡合并 冲击单音 

分 类 号：O354.4[理学—流体力学] O358[理学—力学]