Porous materials are widely used for noise control treatments. Sound-absorb cotton is commonly used in the transportation industry such as automobiles and airplanes because of its excellent sound absorption performance. In this paper, two typical acoustical models were used to evaluate the sound absorption coefficient of sound-absorb cotton. By comparing the measurement results with those of acoustical models, suitable model for sound-absorb cotton can be found. Physical parameters are measured and calculated by experimentally and inverse methods. Porosity and density are directly measured, while airflow resistivity is measured by changing boundary conditions between sample and container. Tortuosity and characteristic length are identified by using material acoustic parameters identification software, when samples considered as limp and rigid skeleton-type respectively. When all parameters of the samples are obtained, then the sound absorption coefficient of the sample can be simulated by material acoustic simulation software. This paper, also investigated the effect on sound absorption coefficient by airflow resistivity due to different boundary conditions. The conclusion of the theoretical model applicable to sound-absorb cotton can be drawn from the results obtained, also proved the best method of airflow resistivity measure.

多孔材料被广泛用于噪声控制处理。吸音棉由于其优异的吸声性能而常用于诸如汽车和飞机的运输行业。在本文中，使用两种典型的声学模型来评估吸声棉的吸声系数。通过将测量结果与声学模型的测量结果进行比较，可以找到适合吸音棉的模型。物理参数通过实验和逆方法进行测量和计算。孔隙率和密度可以直接测量，而气流阻力则可以通过改变样品和容器之间的边界条件来测量。通过使用材料声学参数识别软件来识别曲折度和特征长度，当样品分别被认为是li脚型和刚性骨架型时。当获得样品的所有参数时，可以通过材料声学模拟软件来模拟样品的吸声系数。本文还研究了不同边界条件对气流阻力的影响对吸声系数的影响。从得到的结果可以得出适用于吸声棉的理论模型的结论，也证明了最佳的阻风性测量方法。