基于分布式体积速度传感的结构声辐射有源控制实验研究
Experimental study on active structural acoustic control based on distributed structural volume velocity sensors
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摘要: 以简支矩形薄板为研究对象,首先在波数域内对结构振动体积速度与辐射声功率的关系进行分析,推导出反映结构模态对体积速度贡献规律的数学表达式。在此基础上,结合PVDF (Polyvinylidene Fluoride)压电薄膜的电荷输出方程,利用三角函数的正交性,给出一种方法来设计体积速度传感器,并针对具体模型进行了结构体积速度测量实验。结果表明,所设计的分布式体积速度传感器具有较好的传感精度。在此基础上,利用所设计的传感器进行了结构声辐射有源控制实验研究,分别针对单频和带宽信号激励情况下的有源控制实验取得了满意的控制效果,从而验证了本文PVDF体积速度传感器设计方法的正确性以及通过PVDF膜传感结构声辐射并作为误差传感器进行有源控制的有效性。Abstract: Using a simply supported rectangular plate as analytical model,firstly the relationship between structural surface volume velocity and sound power radiated by the plate was analyzed in the wave-number domain,the mathematical formula that indicates the contributions of structural modes to the volume velocity was derived.Based on this expression,combined with charge output equation of the PVDF(Polyvinylidene Fluoride) piezoelectric film and orthogonal property of trigonometric function,a approach for volume velocity sensor was presented.An experiment for measuring structural volume velocity was conducted,and good accuracy was obtained.On the basis,experiments for active structural acoustic radiation control were carried on for single frequency and band-limited excitations.Excellent control effects were obtained,and so the validity of this design approach of the distributed volume velocity sensor and the effectiveness of active structural acoustic control using the designed sensor were further verified.