Baccouche Ryan, Moreau Soléne, Ben Tahar Mabrouk
Sorbonne University, Université de Technologie de Compiègne, CNRS, Unité Mixte de Recherche 7337 Roberval, Centre de Recherche Royallieu, CS 60319, 60203 Compiègne cedex, France.
J Acoust Soc Am. 2017 Jun;141(6):4168. doi: 10.1121/1.4983653.
Passive acoustic treatments, also called liners, are the main solution to noise problems. The Single Degree Of Freedom (SDOF) acoustic treatment, composed of a thin material (perforated plate) affixed to air cavities with a rigid bottom, constitutes a solution. Predicting sound level reduction by an SDOF treatment requires reliable acoustic impedance models. An experimental/numerical method has been developed for a duct with an acoustic treatment to test acoustic impedance models of SDOF treatment with a multimodal propagation in the presence of a mean flow. This method is based on the comparison of experimental results from an aeroacoustic bench composed of a circular duct with a treated area, and numerical results from an FEM-PML axisymmetric model based on Galbrun's equation. The numerical results are confronted with experimental results to test impedance models up to M=±0.25.
被动声学处理，也称为衬里，是解决噪声问题的主要方法。单自由度（SDOF）声学处理由附着在具有刚性底部的气腔上的薄材料（穿孔板）组成，是一种解决方案。预测SDOF处理带来的声级降低需要可靠的声阻抗模型。已开发出一种实验/数值方法，用于对带有声学处理的管道进行测试，以在存在平均流的情况下通过多模态传播来测试SDOF处理的声阻抗模型。该方法基于由带有处理区域的圆形管道组成的气动声学试验台的实验结果与基于加尔布伦方程的有限元-完全匹配层（FEM-PML）轴对称模型的数值结果进行比较。将数值结果与实验结果进行对比，以测试高达M = ±0.25的阻抗模型。
