Chiang Y K, Choy Y S
Department of Mechanical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong Special Administrative Region, China.
J Acoust Soc Am. 2018 Jan;143(1):538. doi: 10.1121/1.5021334.
The acoustic performance of a microperforated panel (MPP) absorber array in the nonlinear regime is investigated both numerically and experimentally. The MPP absorber array is constructed by three parallel-arranged MPP absorbers with different cavity depths. A finite element model is used to simulate the acoustic response of the MPP absorber array by adopting the nonlinear impedance model. The results show that the absorption of the MPP absorber array is affected by the incident sound pressure when it is beyond around 100 dB. With appropriate structural and perforation property of MPP, the MPP absorber array in non-linear regime outperforms that in linear regime due to the improvement of equivalent acoustic impedance matching with ambient air over wide frequency range. However, when the sound pressure excitation is too high, the local resonance effect of the resonating component MPP absorber is diminished and the sound absorption is decreased. With the carefully chosen properties of MPP, the performance degradation induced by panel vibration can be avoided. An optimal set of MPP properties to avoid the performance degradation induced by panel vibration is determined. The measured normal absorption coefficients of a prototype MPP absorber array compare well with the numerical prediction in both linear and nonlinear regimes.
对微穿孔板（MPP）吸声器阵列在非线性状态下的声学性能进行了数值和实验研究。MPP吸声器阵列由三个具有不同腔深的平行排列的MPP吸声器构成。采用有限元模型，通过非线性阻抗模型模拟MPP吸声器阵列的声学响应。结果表明，当入射声压超过约100 dB时，MPP吸声器阵列的吸声受到影响。对于具有合适结构和穿孔特性的MPP，由于在宽频率范围内与周围空气的等效声阻抗匹配得到改善，非线性状态下的MPP吸声器阵列优于线性状态下的。然而，当声压激励过高时，谐振部件MPP吸声器的局部共振效应减弱，吸声降低。通过精心选择MPP的特性，可以避免由面板振动引起的性能下降。确定了一组避免由面板振动引起性能下降的最佳MPP特性。原型MPP吸声器阵列的实测法向吸声系数在线性和非线性状态下均与数值预测结果吻合良好。
