We propose a physical optics approach to compute the volume radiative properties and surface reflectivity of porous ceramics composed of a weakly absorbing solid matrix containing low fractions of heterogeneities (pores or particles). Our approach accounts for dependent scattering between heterogeneities that are small and close to each other compared to the wavelength, and only requires the 3D microstructure and complex refractive indexes of constituent phases as input. We performed numerical validation of our models on reference microstructures with known solutions, and showed that an accuracy of 5% is achieved. We then applied our approach to compute the spectral volume and surface radiative properties of tomography-reconstructed porous alumina samples of various porosities up to 30%. Microstructure-property relations are extracted from numerical results, and are compared to several analytical relations in order to assess their applicability in the studied material.

我们提出了一种物理光学方法来计算多孔陶瓷的体积辐射特性和表面反射率，该多孔陶瓷由含有低比例异质性（孔或颗粒）的弱吸收固体基质组成。我们的方法考虑了与波长相比较小且彼此接近的异质性之间的相关散射，并且只需要 3D 微观结构和组成相的复杂折射率作为输入。我们使用已知解决方案在参考微结构上对我们的模型进行了数值验证，结果表明实现了 5% 的准确度。然后，我们应用我们的方法来计算高达 30% 的各种孔隙率的断层扫描重建多孔氧化铝样品的光谱体积和表面辐射特性。