Abstract Differences in the structure and dynamics of nominally two-dimensional turbulent wakes are investigated experimentally for a thin flat plate, normal to a uniform flow, with two different end conditions: with and without end plates. Both cases are characterized by Karman-like vortex shedding with broadband low frequency unsteadiness. Both wakes evidence a low frequency flapping motion in addition to the slowly drifting base flow common to cylinder wakes. For the case without end plates, an interaction between the drift motion and the vortex formation process is associated with a much stronger modulation of the quasiperiodic vortex shedding amplitude when compared to the case with end plates where a flapping motion is more strongly expressed. These dynamics underlie structural differences in the mean wake and Reynolds stress fields.

中文翻译：

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名义二维薄平板的端部效应

摘要 通过实验研究了名义二维湍流尾流的结构和动力学差异，薄平板垂直于均匀流动，具有两种不同的端部条件：带端板和不带端板。这两种情况的特点是卡门式涡旋脱落和宽带低频不稳定。除了圆柱尾流常见的缓慢漂移的基流之外，这两个尾流都证明了低频扑翼运动。对于没有端板的情况，与带有端板的情况相比，漂移运动和涡旋形成过程之间的相互作用与准周期涡旋脱落幅度的更强调制相关，后者更强烈地表达了扑动运动。这些动力学是平均尾流和雷诺应力场中结构差异的基础。