Development and Characterization of Ultra-High Frequency Resonance-Enhanced Microjet Actuator
Development and Characterization of Ultra-High Frequency Resonance-Enhanced Microjet Actuator
复制标题
超高频共振增强微射流执行器的开发和表征
DOI：
10.2514/6.2013-2476
复制
发表时间：
2013
期刊：
影响因子：
2.5
通讯作者：
F. Alvi
中科院分区：
文献类型：
--
作者：
P. Upadhyay;J. Gustavsson;F. Alvi
对于需要非常高频率激励的流量控制应用，机械致动器通常缺乏在高速流中持续有用的耐久性或控制权威。由于所涉及的致动器的频率和振幅的限制，过去尝试的高频激励被限制为具有合理控制权限的低频致动或具有有限控制权限的高频致动。在本论文中，共振增强微喷射致动器的先前开发的扩展已经进行了扩展的频率范围超出先前研究的范围。使用集总元件模型，以及在以前的研究中开发的经验关系，两个致动器已被设计与标称频率为25 kHz和60 kHz。使用声学测量以及使用微纹影设置的光学诊断进行了广泛的台式表征，以表征致动器的频率和振幅。致动器在20.3-27.8 kHz和54.8-78.2 kHz的频率范围内执行，分别作为NPR和冲击高度的函数。除了提供有关致动器流动物理和致动器性能随操作条件变化的信息外，这些测试还用于开发一种易于集成的超高频致动器，用于超音速自由剪切和共振流中的流动控制。
For flow control applications requiring very high frequency excitation, mechanical actuators often lack the durability or the control authority to be consistently useful in highspeed flows. High frequency excitation attempted in the past has been limited to either low frequency actuation with reasonable control authority or high frequency actuation with limited control authority due to limitation in frequency and amplitude of the actuators involved. In the present paper, an extension of previous development of the Resonance Enhanced Microjet actuators has been undertaken to extend the range of frequencies accessible beyond the range previously studied. Using lumped element model as well as empirical relationships developed in previous studies, two actuators have been designed with nominal frequencies of 25 kHz and 60 kHz. Extensive bench top characterization using acoustic measurements as well as optical diagnostics using a micro-schlieren setup was employed to characterize the frequency as well as amplitude of the actuator. The actuators performed at a range of frequencies 20.3-27.8 kHz and 54.8-78.2 kHz, respectively, as a function of NPR and impingement height. In addition to providing information on the actuator flow physics and the performance of the actuators with variations in operating conditions, the tests serve to develop an easy-to-integrate ultra-high frequency actuator for flow control in supersonic free shear and resonant flows.