基于压电智能材料的自适应吸声实验研究

Adaptive control for underwater sound absorption using piezocomposite smart material

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。

An active underwater broadband sound absorption method was posed,in which a piece of PVDF（poly vinylidene fluoride） piezocomposite smart material was used as absorption material.An adaptive feedforward control system was constructed based on the filter-X LMS algorithm.A kind of method easy to be implemented in engineering for secondary path modeling,based on the delay-LMS algorithm,was presented.The reference signal and error signal of the control system were taken through separating out the incident and the reflection sound pressure from the acoustic field by using the digital time delay system.The experiments for active duct noise control were accomplished in a pulse tube.It is shown that with active control the PVDF piezocomposite smart material can absorb almost all of the low frequency incident sound pressure.