This manuscript presents a simplified analysis for estimating anisotropic, non-homogeneous extinction coefficients in porous solids as a function of the pore morphology and size distribution. The model contains two main simplifications: (1) the pore network consists of hollow interspersed spheres and cylinders, and (2) each surface exchanges radiation (through diffuse emission) only with itself and adjacent surfaces. The model yields photon flight length (PFL) probability distribution functions (PDFs), describing Beerian and non-Beerian anisotropic extinction processes. The method is three orders of magnitude faster than the Monte Carlo Ray Tracing Method (MCRT), yielding Root Mean Square Errors between 0 and 35% for the PFL–PDFs and 0–25% for the anisotropic extinction coefficients. Finally, this work presents a local geometric criterium determining whether the model applies to some given area of the porous solid, so it remains useful even when not applicable to the whole domain.

中文翻译：

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考虑球形和圆柱形孔网络的多孔固体中各向异性非均匀消光系数的简化估计

该手稿提供了一种简化分析，用于估计多孔固体中的各向异性、非均匀消光系数作为孔形态和尺寸分布的函数。该模型包含两个主要的简化：（1）孔隙网络由空心散布的球体和圆柱体组成，（2）每个表面仅与自身和相邻表面交换辐射（通过漫射发射）。该模型产生光子飞行长度 (PFL) 概率分布函数 (PDF)，描述 Beerian 和非 Beerian 各向异性消光过程。该方法比蒙特卡罗射线追踪方法 (MCRT) 快三个数量级，PFL-PDF 的均方根误差为 0 到 35%，各向异性消光系数为 0-25%。最后，