几何因素对多压电膜式零质量射流激励器性能的影响

Geometry Parameter Effect on Performance of Multi-Diaphragm Piezoelectric Synthetic Jet Actuator

利用热线风速仪,在最佳激振频率f=560 Hz时,研究了不同孔径、不同孔深、不同小孔出口几何形状等对多压电膜式零质量射流激励器性能的影响。实验结果表明:所用激励器的最佳孔径为2.5 mm,最佳孔深为2 mm,最佳深径比为0.8。激励器射流出口为锥孔要比为直孔好得多。锥孔在流场中心线上距离激励器出口5<y/d<18范围内,射流速度几乎不变。最后利用CFD数值模拟直观地显示了射流出口的涡结构,说明了几何尺寸产生影响的根源。

Using the hotwire anemometry, the experimental study is carried out on a novel multi-diaphragm piezoelectric synthetic jet actuator （PE-SJA）. The study includes the effects of the geometry parameters（such as the diameter, the depth and the exit shape of the orifice） on the performance of the multi-diaphragm piezoelectric synthetic jet actuator. The experimental result shows that at f=560 Hz, the optimum diameter and the depth of the orifice is 2.5 mm and 2 mm, respectively. Therefore,the optimum depth/diameter ratio is 0. 8. And the performance of the multi-diaphragm PE-SJA with taper-jet exit orifice is much better than that of the straight orifice. During 5〈y/d〈18 along the axis of the orifice exit flowfield, the velocity of the SJA is almost constant. Furthermore, CFD simulation can observe the vortex structure of the flowfield.