Generation conditions of streamwise vortex in supersonic flat-plate boundary layer
-
摘要: 针对马赫数为4.5的超声速平板边界层,基于线性稳定性理论(LST)选取初始扰动组合,通过直接数值模拟(DNS),计算了第一模态不稳定波扰动组合沿流向演化生成流向涡的过程。采用改进Omega-Liutex旋涡识别方法进行涡识别,结合流向不同位置截面的流线图,分析了流向涡的生成特性。根据流向涡在zy截面内的流线特征,提出了流向涡的生成条件,研究发现:流向涡可以直接通过一对展向对称的第一模态不稳定斜波扰动与基本流叠加得到,不是必须经过非线性作用。Abstract: The initial disturbance combinations were selected based on the linear stability theory (LST) for a supersonic flat-plate boundary layer with Mach number of 4.5.Through direct numerical simulation (DNS),the generation process of streamwise vortex due to the evolution of combined first-mode unstable waves along the flow direction was simulated.Based on the vortex identification method of modified Omega-Liutex and the streamline diagram at different positions in the streamwise direction,the generation characteristics of streamwise vortex were analyzed,and its generation conditions were proposed according to the features of streamline in zy plane.It was found that streamwise vortex can be obtained directly by superimposing a pair of first-mode unstable oblique waves and basic flow,in which nonlinear action was not necessary.
-
[1] 张涵信,周恒.流体力学的基础研究[J].世界科技研究与发展,2001,23(1):15-18. [2] ROBINSON S K.Coherent motions in the turbulent boundary layer[J].Annual Review of Fluid Mechanics,1991,23(1):601-639. [3] HEAD M R,BANDYOPADHYAY P.New aspects of turbulent boundary-layer structure[J].Journal of Fluid Mechanics,1981,107:297-338. [4] ACARLAR M S,SMITH C R.A study of hairpin vortices in a laminar boundary layer:Part Ⅰ hairpin vortices generated by a hemisphere protuberance[J].Journal of Fluid Mechanics,1987,175:1-41. [5] ACARLAR M S,SMITH C R.A study of hairpin vortices in a laminar boundary layer:Part Ⅱ hairpin vortices generated by fluid injection[J].Journal of Fluid Mechanics,1987,175:43-83. [6] LIAN Q X.A visual study of the coherent structure of the turbulent boundary layer in flow with adverse pressure gradient[J].Journal of Fluid Mechanics,1990,215:101-124. [7] ROGERS M M,MOIN P.The structure of the vorticity field in homogeneous turbulent flows[J].Journal of Fluid Mechanics,1987,176:33-66. [8] JEONG J,HUSSAIN F,SCHOPPA W,et al.Coherent structure near the wall in a turbulent channel flow[J].Journal of Fluid Mechanics,1997,332:185-214. [9] 周恒,陆昌根,罗纪生.湍流边界层近壁区单个相干结构的模拟[J].中国科学:A辑,1999,29(4):366-372. [10] ZHOU J,ADRIAN R J,BALACHANDAR S,et al.Mechanisms for generating coherent packets of hairpin vortices in channel flow[J].Journal of Fluid Mechanics,1999,387:353-396. [11] SCHOPPA W,HUSSAIN F.Coherent structure generation in near-wall turbulence[J].Journal of Fluid Mechanics,2002,453:57-108. [12] PIROZZOLI S,BERNARDINI M,GRASSO F.Characterization of coherent vortical structures in a supersonic turbulent boundary layer[J].Journal of Fluid Mechanics,2008,613:205-231. [13] 陈林,唐登斌,刘超群.转捩边界层中次生流向涡演化的数值研究[J].应用数学和力学,2011,32(4):428-436. [14] SAYADI T,HAMMAN C W,MOIN P.Direct numerical simulation of complete H-type and K-type transitions with implications for the dynamics of turbulent boundary layers[J].Journal of Fluid Mechanics,2013,724:480-509. [15] ZHAO Y,LEI C,PATTERSON J C.The K-type and H-type transitions of natural convection boundary layers[J].Journal of Fluid Mechanics,2017,824:352-387. [16] 李玲玉,刘建新.高超声速边界层基频二次失稳条纹结构的稳定性研究[EB/OL].[ 2021-04-10].https:∥kns.cnki.net/kcms/detail/51.1192.TK.20210310.1531.004.html [17] HUANG Z,ZHOU H,LUO J.Direct numerical simulation of a supersonic turbulent boundary layer on a flat plate and its analysis[J].Science in China:Series G,2005,48(5):626-640. [18] JEONG J,HUSSAIN F.On the identification of a vortex[J].Journal of Fluid Mechanics,1995,285:69-94. [19] HUNT J,WRAY A A,EddiesMOIN P.,streams,and convergence zones in turbulent flows[R].Center for Turbulence Research Report,CTR-S88,1988. [20] LIU C,WANG Y,YANG Y,et al.New omega vortex identification method[J].Science China Physics,Mechanics and Astronomy,2016,59(8):684711.1-684711.9. [21] LIU C,GAO Y,TIAN S,et al.Rortex:a new vortex vector definition and vorticity tensor and vector decompositions[J].Physics of Fluids,2018,30(3):035103.1-035103.25. [22] LIU C,LIU J.Modified normalized rortex/vortex identification method[J].Physics of Fluids,2019,31(6):061704.1-061704.8. [23] WANG Z,CHANG J,ZHANG J,et al.Evolution of subsonic and supersonic corner vortices in a supersonic cascade[J].Aerospace Science and Technology,2019,95(10):105509.1-105509.58.
点击查看大图
计量
- 文章访问数: 103
- HTML浏览量: 7
- PDF量: 170
- 被引次数: 0