In this paper, radiative characterization of a packed bed of novel three-dimensionally ordered macroporous (3DOM) ceria particles is performed in the spectral range relevant to solar thermochemical processes, 0.35–2.2 μm. Normal–hemispherical transmittance and reflectance of three samples of various thicknesses are measured. Monte Carlo ray-tracing (MCRT) and discrete ordinate methods are employed to identify transport scattering albedo and transport extinction coefficient in the spectral range corresponding to weak absorption in the semi-transparency band of ceria. 3DOM ceria particles are characterized by weaker scattering in comparison to sintered ceria ceramics, and increased transparency in the near-infrared spectral range 0.7–2 μm. The ordered pore-morphology of the 3DOM ceria after thermochemical redox cycling between temperatures 1373 K and 1073 K is altered due to sintering of walls of the 3DOM structure. The absorption coefficient of the packed bed is found to be practically independent of morphology. Radiative characterization of 3DOM ceria ceramics before and after thermochemical cycling suggests that preserving the 3DOM structure can lead to scattering characteristics that permit longer attenuation path lengths of incident concentrated solar radiation in the material, as well as be favorable for confinement of the near-infrared radiation during thermochemical cycling leading to favorable thermochemical conditions for fuel production.
Effect of Morphology on Spectral Radiative Properties of Three-Dimensionally Ordered Macroporous Ceria Packed Bed
Campus du Moulin de la Housse - BP 1039,
51687 Reims Cedex 2,
Contributed by the Heat Transfer Division of ASME for publication in the Journal of Heat Transfer. Manuscript received January 7, 2013; final manuscript received June 24, 2013; published online October 14, 2013. Assoc. Editor: Zhixiong Guo.
- Views Icon Views
- Share Icon Share
- Search Site
Ganesan, K., Randrianalisoa, J., and Lipiński, W. (October 14, 2013). "Effect of Morphology on Spectral Radiative Properties of Three-Dimensionally Ordered Macroporous Ceria Packed Bed." ASME. J. Heat Transfer. December 2013; 135(12): 122701. https://doi.org/10.1115/1.4024942
Download citation file: