The flow around two bluff bodies in tandem is an interesting phenomenon whose nature strongly depends on the distance between the bodies. In this work oil smoke visualizations of the flow around two normal flat plates in tandem configuration are compared with phase averaged Laser Doppler Anemometry measurements of the flow field for a full period. Phase averaging is exploited to resolve the mean time evolution of the flow and the signal from a single constant temperature hot wire probe is employed as phasing reference. The flow-field information obtained from visualizations agrees well with quantitative indications provided by measures, and the comparison allows to precisely understand what information can be extracted from simple visualizations. As a result, new insight in flow mechanism is obtained from the analysis of the flow data showing that, for the analyzed plate distance, the gap between the two plates behaves substantially as a cavity while the vortex formation process takes place in the wake region behind the aft plate.

中文翻译：

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基于LDA信号相位平均的两个正常平板的相互作用尾迹研究

串联的两个钝体周围的流动是一种有趣的现象，其性质在很大程度上取决于物体之间的距离。在这项工作中，将串联配置的两个正常平板周围流动的油烟可视化与整个周期的流场的相位平均激光多普勒风速测量进行了比较。相位平均被用来解决流动的平均时间演变，来自单个恒温热线探头的信号被用作相位参考。从可视化中获得的流场信息与测量提供的定量指示非常吻合，并且通过比较可以准确地了解可以从简单的可视化中提取哪些信息。结果，从流动数据的分析中获得了流动机制的新见解，表明，