可控声阻抗声衬控制系统设计及实验研究

The design and experimental investigation of control system for acoustic liner with controllable impedance

为了克服传统声衬在实际应用中的限制，介绍了一种可控声抗的声衬，并设计了一套控制系统实现了这种声衬声阻抗的有源控制，使这种声衬的吸声系数在任意声源频率范围内始终保持最优值或定值，从而满足一定的阻抗条件。这个工作对发动机吸声降噪有源控制及通过压气机机匣处理抑制颤振具有重要实际意义。

In this study, a kind of new acoustic liner with controllable impedance based on vortex sound theory has been introduced. The impedance of this kind of liner can be controlled according to external sound source condition so that the sound absorption coefficient of the liner can keep optimal or the liner can satisfy requested impedance condition under any sound source condition. A set of active control system has been designed for this kind of liner in this investigation. The quality of this kind of liner with control system has been improved greatly. Especially with the appearance of concept about active control of unsteady flow of the compressor,it will be found that this kind of liner with controllable impedance would be more valuable for active control of engine noise and advanced casing treatment ofcompressor.