半钹形压电合成射流驱动器及其特征参数研究

Research on Piezoelectric Synthetic Jet Actuator with Half Cymbal Membrane and Its Geometric Parameters

采用了一种新型驱动结构,半钹形压电金属复合结构,以提高合成射流驱动器出口射流速度,增强其流场主动控制能力。研究了3种半钹形隔膜及一种传统平板形驱动隔膜的合成射流驱动器,分别对其频率响应特性、射流时均速度沿出口中心线方向以及出口两侧的分布做了比较分析。结果表明3种半钹形隔膜驱动器的出口射流时均速度比平板形驱动器分别提高了51%,26%和48%。此外,还研究了半钹形驱动器的腔体结构特征尺寸对出口射流速度的影响,结果表明驱动器腔体结构特征尺寸存在着优化组合,使得出口射流速度更大,而且沿出口中心线方向上的速度衰减降低。

A new piezoelectric synthetic jet actuator （PSJA） equipped with a half cymbal metal-piezoelectric composite membrane is proposed for the purpose of improving the output jet velocity and enhancing the controlling ability of synthetic jet actuator （SJA） for active flow control. Three kinds of half cymbal structure membranes as well as a plane one are manufactured and studied. The frequency responses and time-averaged jet velocity along the axial distance as well as along both sides from the exit of the SJA are measured and compared. The results show that the time-averaged jet velocities synthesized from the three actuators with half cymbal membranes improved by 50%, 25%, and 46% respectively as compared with the actuator with a plane embrane. Then the effects of cavity geometric parameters of PSJA with half cymbal membranes on output jet velocity are experimentally investigated. The results show that there is an optimal combination of these parameters that causes higher time-averaged jet velocity and lower velocity decay along the axial distance form exit.