The effect of base suction on flapping and energy harvesting through the piezoelectric membrane in the wake of a cylindrical bluff body is studied in this paper by carrying out a series of wind tunnel experiments. The effect of S/D (ratio of the distance between the cylinder and membrane to the cylinder diameter), L/D (ratio of the membrane length to the cylinder diameter), and flow speed on the flapping dynamics and energy generation from the polyvinylidene fluoride membrane placed behind the bluff body was studied. Different flapping modes were found from optimal coupling to fully deformed. The flapping motion of the membrane was determined by using a high-speed camera, and an oscilloscope was used for the measurement of the generated voltages. Also, the flapping dynamics and output voltages were extensively studied in the sub and post-critical regions by varying the S/D ratio, L/D ratio, and flow velocity. An increase of 38% in energy harvesting is observed when the piezomembrane was placed at L/D = 1 and S/D = 2 with free stream velocity U = 10 m/s. An increase or decrease in voltages is attributed to the observation that the amount of harvested energy changes by varying the stated parameters. Optimum energy can be harvested by fine-tuning of flow and geometrical parameters and adjusting the piezoelectric flag in the specified range.

中文翻译：

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钝体后能量收集的实验研究

本文通过一系列风洞实验研究了底部吸力对圆柱形钝体尾流通过压电膜进行扑动和能量收集的影响。S/D（圆柱体和膜之间的距离与圆柱体直径的比值）、L/D（膜长度与圆柱体直径的比值）和流速对聚偏乙烯的扑动动力学和能量产生的影响研究了置于钝体后面的氟化物膜。从最佳耦合到完全变形，发现了不同的扑动模式。使用高速相机确定膜的扑动运动，并使用示波器测量产生的电压。还，通过改变 S/D 比、L/D 比和流速，在亚临界和后临界区域广泛研究了扑动动力学和输出电压。当压电膜放置在 L/D = 1 和 S/D = 2 且自由流速度 U = 10 m/s 时，观察到能量收集增加了 38%。电压的增加或减少归因于观察到的收获能量的量通过改变所述参数而改变。可以通过微调流量和几何参数并在指定范围内调整压电标志来收集最佳能量。电压的增加或减少归因于观察到的收获能量的量通过改变所述参数而改变。可以通过微调流量和几何参数并在指定范围内调整压电标志来收集最佳能量。电压的增加或减少归因于观察到的收获能量的量通过改变所述参数而改变。可以通过微调流量和几何参数并在指定范围内调整压电标志来收集最佳能量。