## 2 Model Analysis  
The predictive model used in this study is the Horoshenkov three-parameter model [33], which simplifies the JCAL six-parameter model by expressing the two characteristic lengths and two permeability parameters in terms of the median pore size and the standard deviation of the pore size. Specifically, the model is expressed as follows [33]:  
\[\Lambda=\bar{s}e^{-\frac{5}{2}(\sigma_{\mathrm{s}}\log 2)^{2}} \tag{1}\]  
\[\Lambda^{\prime}=\bar{s}e^{\frac{3}{2}(\sigma_{\mathrm{s}}\log 2)^{2}} \tag{2}\]  
\[k_{0}=\frac{\bar{s}^{2}\varphi}{8\alpha_{\infty}}e^{-6(\sigma_{\mathrm{s}} \log 2)^{2}} \tag{3}\]  
\[k_{0}^{\prime}=\frac{\bar{s}^{2}\varphi}{8\alpha_{\infty}}e^{6(\sigma_{ \mathrm{s}}\log 2)^{2}} \tag{4}\]  
\[\alpha_{\infty}=e^{4(\sigma_{\mathrm{s}}\log 2)^{2}} \tag{5}\]  
where \(\varphi\) is the porosity, \(\bar{s}\) is the median pore size, \(\sigma_{\mathrm{s}}\) is the standard deviation of pore size, \(\Lambda\) is the viscous characteristic length, \(\Lambda^{\prime}\) is the thermal characteristic length, \(k_{0}\) is the viscous flow resistance, \(k_{0}^{\prime}\) is the thermal flow resistance, and \(\alpha_{\infty}\) is the tortuosity factor. Compared to other semi-phenomenological models, this model requires fewer parameters (the complete formula of the three-parameter model is shown in Supplementary Materials S1), and key parameters such as porosity, median pore size, and pore size standard deviation can be directly measured. This significantly simplifies the process of predicting acoustic performance. Furthermore, its predictions are almost identical to those of the Johnson-Champoux-Allard-Lafarge (JCAL) model. To thoroughly investigate the specific effects of three key parameters--porosity, average pore diameter, and pore diameter standard deviation--on the sound absorption performance of materials, this section employs COMSOL Multiphysics 6.1 software for simulation analysis. A three-dimensional (3D) finite element model of porous materials was developed using the Pressure Acoustics module, as illustrated in Figure 1. The model incorporates both the air layer and porous material section of an impedance tube, complete with mesh generation and sensor field point establishment. The impedance tube configuration features a plane wave radiation source at one end and a rigid wall boundary condition at the opposite end. The porous medium acoustic model utilizes the three-parameter approximation \"JCAL\" model. The simulation encompasses 626 frequency points from 50 to 6300 Hz with 10 Hz increments, during which parametric sweeps were conducted for material porosity, average pore diameter, and pore diameter standard deviation to comprehensively analyze their individual and combined effects on sound absorption performance. To simulate the acoustic performance of actual fiber porous materials, specific parameter ranges were defined based on a previous actual test. The porosity was set within the range of 90-98%, the median pore size ranged from 40 \(\upmu\)m to 120 \(\upmu\)m, and the pore size standard deviation ranged from 0.1 to 0.3, as shown in Table 1. The thickness of the studied materials was fixed at 3 cm, and the sound absorption performance was calculated over the frequency range of 50-6300 Hz. When analyzing the effect of a single parameter on sound absorption performance, the other two parameters were set to the midpoint of their respective ranges to eliminate interference. The sound absorption performance after parameterized scanning of different factors is shown in Figure 2. Figure 2a-c illustrates the effects of changes in porosity, pore size standard deviation, and median pore size on the sound absorption coefficient, respectively, while Figure 2d-f depicts the corresponding noise reduction coefficient (NRC) and average sound absorption coefficient (AAC).