基于压电智能材料的自适应吸声实验研究

提出了用压电材料进行水下主动宽带低频吸声的方法，用PVDF复合智能材料作为主动吸声系统中的吸声材料，在滤波-X LMS算法基础上，研究了一种在工程中实现简便的次级通道建模方法——通道时延估计法。构建了数字时延控制系统，直接从实际声场中分离入射声波与反射声波作为控制系统的参考信号和误差信号，在脉冲声管中进行了管道声有源吸声控制实验。实验结果表明，在施加控制的情况下PVDF压电智能材料能有效地对低频入射声进行吸收。

Adaptive control for underwater sound absorption using piezocomposite smart material

This paper poses an active underwater broadband sound absorption method, in which a piece of PVDF piezocomposite smart material is used as the absorption material. A adaptive feedforward control system has been construct based on the filter-X LMS Algorithm. A kind of easy to implement in engineering method for secondary path modeling, based on the Delay-LMS algorithm, has been studied. The reference signal and error signal of the control system are received through separating the incident and the reflection sound pressure from out of the acoustic field using the digital time delay system. The experimental research of active duct noise control in the the pulse tube is accomplished. It is shown that the PVDF piezocomposite smart material can absorb almost all of the low frequency incident sound pressure with active control.