Fig. 1. Schematic of computational model.计算模型示意图

Fig. 2. Comparison between numerical and experimental results: (a) Mean velocity; (b) turbulent intensity.数值与实验对比　(a) 时均速度; (b) 流向湍流强度

Fig. 3. Vorticity thickness variations versus stream wise direction for different mesh distributions.不同网格条件下混合层的涡量厚度沿流向的变化

Fig. 4. Distribution of input continuous signal.连续控制信号分布

Fig. 5. Distribution of vortex structures of free shear layers.自由剪切层流场涡结构分布

Fig. 6. Vortex structures distribution under inlet forcing with high frequency (f = 20 kHz). 高频入流激励下流场涡结构的分布 (f = 20 kHz)

Fig. 7. Pressure distribution between the vortex core in the flow field.流场涡核之间的压力分布

Fig. 8. Frequency spectrum distribution under inlet forcing with high frequency (f = 20 kHz): (a) X/H = 1; (b) X/H = 4 高频入流激励下频谱分布 (f = 20 kHz)　(a) X/H = 1; (b) X/H = 4

Fig. 9. Vortex structures distribution under inlet forcing with low frequency (f = 5 kHz). 低频入流扰动下剪切层流场涡结构分布 (f = 5 kHz)

Fig. 10. Frequency spectrum distribution under inlet forcing with low frequency (f = 5 kHz): (a) X/H = 1; (b) X/H = 4 低频入流激励下频谱分布 (f = 5 kHz)　(a) X/H = 1; (b) X/H = 4

Fig. 11. Dynamic engulfment process of vortex structures.涡结构的动态吞噬过程

Fig. 12. Vorticity thickness distribution versus streamwise direction.剪切层涡量厚度随流向距离的分布

Fig. 13. Spatial correlation distributions of free shear layers in different streamwise positions: (a) (1.5, 0.6); (b) (2.4, 0.6); (c) (3.5, 0.6); (d) (5.1, 0.6).自由剪切层中不同流向位置处空间相关性分布　(a) (1.5, 0.6); (b) (2.4, 0.6); (c) (3.5, 0.6); (d) (5.1, 0.6)

Fig. 14. Spatial correlation distributions with low frequency forcing in different streamwise positions: (a) (2.0, 0.6); (b) (2.7, 0.6); (c) (3.5, 0.6); (d) (5.1, 0.6).低频激励下不同流向位置处空间相关性分布　(a) (2.0, 0.6); (b) (2.7, 0.6); (c) (3.5, 0.6); (d) (5.1, 0.6)

Fig. 15. Schematic of vortex size and structure angle.拟序结构的大小和结构角示意图

Fig. 16. Non-dimensional structure size distribution versus streamwise direction.无量纲结构大小沿流向的分布

Fig. 17. Structure angle distribution versus streamwise direction.结构角沿流向的分布