The design and experimental investigation of control system for acoustic liner with adjustable imped

来源 :Chinese Journal of Acoustics | 被引量 : 0次 | 上传用户:baei
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A kind of new acoustic liner with adjustable impedance has been proposed. At the same time, a set of control system has been designed for this kind of liner. Many experimental results have been obtained based on this control system. In fact, the present investigation shows the possibi1ity of active control of sound absorption coefficient or impedance of a liner according to external sound source condition by means of a standing wave tube. The experimental results show that the sound absorption coefficient of the liner can keep optimal under any sound source condition by controlling the cavity depth and the flow rate through the perforated plate of the liner. In addition, hoth the resistance and the reactance of the liner can also be controlled independently corresponding to any given condition. which is necessary to control unsteady How in turbomachinery. A kind of new acoustic liner with adjustable impedance has been proposed. At the same time, a set of control system has been designed for this kind of liner. Many experimental results have been obtained based on this control system. shows the possibi1ity of active control of sound absorption coefficient or impedance of a liner according to external sound source condition by means of a standing wave tube. The experimental results show that the sound absorption coefficient of the liner can keep optimal under any sound source source condition by控制 the cavity depth and the flow rate through the perforated plate of the liner. In addition, hoth the resistance and the reactance of the liner can also be controlled optional of any liner.
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