Performance analysis of perforated panel resonator with impedance-decoupling tube-bundles

To solve the problem of coupling of acoustic resistance and acoustic reactance which affects impedance matching in acoustic absorbers, a perforated panel structure with segmented impedance-decoupling tube-bundles (PP-IDTB) is proposed to realize the decoupling of acoustic resistance and acoustic reactance. The decoupling of the acoustic resistance and acoustic reactance of the PP-IDTB can be achieved by adjusting the geometrical parameters of the upper fine tube bundles and the lower thick tube. Theoretical and simulated results show that by changing the diameter of the upper thin tubes, the acoustic resistance can be changed, while the acoustic reactance remains constant, thus the frequency width of the absorption can be adjusted. The acoustic reactance varies with the length of the lower thick tube, while the acoustic resistance remains almost unchanged, thus the peak frequency of absorption can be adjusted. Moreover, impedance decoupling can improve the impedance matching effect in a wide frequency range, further enhance the performance of sound absorption, and broaden the adjustment range of the absorption band. The effectiveness of impedance decoupling in modulating the absorption performance of PP-IDTB is experimentally verified.