Radiative characterization of ceramic foams with microporosity

Abstract

The porous morphology of ceramic foams can significantly influence its heat and mass transport phenomena. Ceramic foams with dual-scale porosity provide flexibility for tailoring the coupled transport characteristics for enhanced performance. We numerically characterized the radiative transport in porous ceria foams with dual-scale porosity, i.e. exhibiting pores in the millimeter range in the micrometer range. Ceria can act as a catalyst- equivalent in high temperature thermochemical reactions for the direct synthesis of solar fuels and its bulk material properties vary significantly with wavelength. The methodology used is based on Monte Carlo methods for the solution of the volume-averaged radiative transfer equations for the determination of macroscopic optical properties such as reflectance or transmittance of a 1D slab. The exact millimeter-scale structure was incorporated by effective transport properties obtained through collision-based Monte Carlo methods. The micrometer- range strut porosity was incorporated using Mie theory and assuming independent scattering. The results allow for guiding the synthesis of ceramic foams with dual-scale porosity for enhanced radiative transport characteristics.