Two challenging tasks in pore-scale modeling of a gas diffusion layer (GDL) are realistic microstructure reconstruction and stress-strain simulation to differentiate the heterogeneous materials. This study proposes a novel method for reconstructing a GDL using fiber tracking technique and pore-scale modeling to investigate its stress-strain and anisotropic transport properties. X-ray computed tomography, fiber tracking, and morphological processing techniques were employed to reconstruct a realistic GDL. Pore-scale modeling was performed to compute the stress-strain, gas diffusivity, and electrical-thermal conductivity at different compression ratios. The sensitivity of compression speed and Young's modulus were investigated to balance the accuracy and computing cost of stress-strain simulation. The results showed that Young's modulus of 1 GPa and compression speed of 3 m/s meet the requirements for both accuracy and computational cost. The reconstructed GDL showed good agreements with the experimental data when considering fibers' orientation, length, and curvature. It was found that the stress among fibers was approximately five times higher than binders. The anisotropic ratios of diffusivity and conductivity decreased from 1.35 to 1.25, and 15 to 5, respectively, as the compression ratio increased to 25%. This study can provide accurate predictions and guidelines for GDL design with low stress and high performance.

气体扩散层 (GDL) 的孔隙尺度建模中的两个具有挑战性的任务是真实的微观结构重建和应力应变模拟以区分异质材料。本研究提出了一种使用纤维跟踪技术和孔隙尺度建模来重建 GDL 的新方法，以研究其应力应变和各向异性传输特性。X 射线计算机断层扫描、纤维跟踪和形态处理技术用于重建真实的 GDL。进行孔隙尺度建模以计算不同压缩比下的应力应变、气体扩散率和电热导率。研究了压缩速度和杨氏模量的敏感性，以平衡应力-应变模拟的准确性和计算成本。结果表明，杨 1 GPa的s模量和3 m / s的压缩速度满足精度和计算成本的要求。在考虑纤维的方向、长度和曲率时，重建的 GDL 与实验数据显示出良好的一致性。发现纤维之间的应力大约是粘合剂的五倍。随着压缩比增加到 25%，扩散率和导电率的各向异性比分别从 1.35 下降到 1.25 和 15 到 5。这项研究可以为低应力和高性能的 GDL 设计提供准确的预测和指导。发现纤维之间的应力大约是粘合剂的五倍。随着压缩比增加到 25%，扩散率和导电率的各向异性比分别从 1.35 下降到 1.25 和 15 到 5。这项研究可以为低应力和高性能的 GDL 设计提供准确的预测和指导。发现纤维之间的应力大约是粘合剂的五倍。随着压缩比增加到 25%，扩散率和导电率的各向异性比分别从 1.35 下降到 1.25 和 15 到 5。这项研究可以为低应力和高性能的 GDL 设计提供准确的预测和指导。