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通过时间模式的直接数值模拟得到来流Mach数为4.5,Reynolds数Reθ=1094的充分发展平板湍流边界层的流场数据库.采用实验研究中常用的检测方法对此流场进行相干结构检测,发现超音速湍流边界层近壁区同样存在相干结构.分析了Mu-level法、第二象限法和VITA法三种条件采样的检测结果,发现Mu-level法检测到的是低速条纹,第二象限法检测到的是低速条纹的上升部分,VITA法检测到的则是从低速条纹区到高速区的交界区.尽管三种方法检测到的是不同的区域,但它们都伴有准流向涡结构.
The flow field database of fully developed turbulent boundary layer with flat Mach number of 4.5 and Reynolds number of Reθ = 1094 is obtained by direct numerical simulation of time mode, and the coherent structure of the turbulent boundary layer is detected by the commonly used detection method in experimental study. There are also coherent structures in the near wall of the supersonic turbulent boundary layer.The results of the Mu-level method, the second quadrant method and the VITA method are also analyzed. It is found that the Mu-level method detects low-speed stripes and the second quadrant Method detects the rising part of the low-speed streaks and the VITA method detects the boundary area from the low-speed streak area to the high-speed area.Although the three methods detect different areas, they are accompanied by quasi-flow vortices .