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.