Phipps Alex, Liu Fei, Cattafesta Louis, Sheplak Mark, Nishida Toshikazu
Department of Electrical and Computer Engineering, University of Florida, Gainesville, Florida 32611-6130.
J Acoust Soc Am. 2009 Feb;125(2):873-81. doi: 10.1121/1.3050287.
This paper demonstrates the system operation of a self-powered active liner for the suppression of aircraft engine noise. The fundamental element of the active liner system is an electromechanical Helmholtz resonator (EMHR), which consists of a Helmholtz resonator with one of its rigid walls replaced with a circular piezoceramic composite plate. For this system demonstration, two EMHR elements are used, one for acoustic impedance tuning and one for energy harvesting. The EMHR used for acoustic impedance tuning is shunted with a variable resistive load, while the EMHR used for energy harvesting is shunted to a flyback power converter and storage element. The desired acoustic impedance conditions are determined externally, and wirelessly transmitted to the liner system. The power for the receiver and the impedance tuning circuitry in the liner are supplied by the harvested energy. Tuning of the active liner is demonstrated at three different sound pressure levels (148, 151, and 153 dB) in order to show the robustness of the energy harvesting and storage system. An acoustic tuning range of approximately 200 Hz is demonstrated for each of the three available power levels.
本文展示了一种用于抑制飞机发动机噪声的自供电有源衬套的系统运行情况。有源衬套系统的基本元件是一个机电亥姆霍兹谐振器（EMHR），它由一个亥姆霍兹谐振器组成，其刚性壁之一被一块圆形压电陶瓷复合板取代。为了进行该系统演示，使用了两个EMHR元件，一个用于声阻抗调谐，一个用于能量收集。用于声阻抗调谐的EMHR与一个可变电阻负载并联，而用于能量收集的EMHR则与一个反激式功率转换器和存储元件并联。所需的声阻抗条件由外部确定，并无线传输到衬套系统。衬套中接收器和阻抗调谐电路的电源由收集到的能量提供。为了展示能量收集和存储系统的稳健性，在三个不同的声压级（148、151和153 dB）下演示了有源衬套的调谐。对于三种可用功率水平中的每一种，都展示了大约200 Hz的声学调谐范围。
