异形腔体压电声衬声学性能

为提高压电声衬对低频噪声的抑制范围,对声衬腔体进行结构优化。利用平面波理论构建了两种曲线管道的声学物理模型,并分别建立了两种模型的传递矩阵,以此作为异形腔体亥姆霍兹共振器传递损失计算的理论依据,并通过仿真验证其正确性。结合压电振子的形变对声衬进行有限元仿真分析,结果表明:在压电振子施加500V驱动电压时,两种声衬频率偏移量分别为115Hz和120Hz。与圆柱形腔体声衬进行对比结果表明:在相同腔体厚度范围内,由曲率越大的曲线所生成的腔体,在相同驱动电压条件下,频率变化率越高,这为今后对声衬腔体结构优化提供一种有效的依据。 

Acoustic performance of piezoelectric acoustic liners with heteromorphic cavity

In order to improve the suppression range of the low frequency noise of the piezoelectric acoustic liners, the structure of the acoustic liner was optimized. By using the plane wave theory, the acoustic physical model of two kinds of curvilinear channels was constructed, and the transfer matrix of two models was established, which can be used as the theoretical basis for loss calculation of the Helmholtz resonator of the heteromorphic cavity; and the correctness was verified by simulation. Combining the deformation of the piezoelectric oscillator with the finite element simulation analysis of the acoustic liner, the results showed that under the condition of applying 500V driving voltage to the piezoelectric oscillator, the two kinds of acoustic systems were offset by 115Hz and 120Hz, respectively. Compared with cylindrical cavity acoustic liner, the results show that: within the same cavity thickness range, for the cavity generated by the curve of greater curvature under the condition of the same driving voltage, the frequency variation is higher, thus providing an effective basis for the acoustic liner cavity structure optimization.