0
Research Papers: Radiative Heat Transfer

Effect of Morphology on Spectral Radiative Properties of Three-Dimensionally Ordered Macroporous Ceria Packed Bed

[+] Author and Article Information
Krithiga Ganesan

Department of Mechanical Engineering,
University of Minnesota,
111 Church Street SE,
Minneapolis, MN 55455

Jaona Randrianalisoa

GRESPI,
University of Reims,
Campus du Moulin de la Housse - BP 1039,
51687 Reims Cedex 2,
Reims, France

Wojciech Lipiński

Department of Mechanical Engineering,
University of Minnesota,
111 Church Street SE,
Minneapolis, MN 55455
e-mail : lipinski@umn.edu

1Corresponding author.

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.

J. Heat Transfer 135(12), 122701 (Oct 14, 2013) (8 pages) Paper No: HT-13-1005; doi: 10.1115/1.4024942 History: Received January 07, 2013; Revised June 24, 2013

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.

FIGURES IN THIS ARTICLE
<>
Copyright © 2013 by ASME
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Fig. 1

Experimental setup for directional–hemispherical transmittance and reflectance measurements with source compartment (#1), integrating sphere (#2), sample holder (#3), and PC for data acquisition (#4). A similar setup was used in [15] for measurement of normal–hemispherical reflectance.

Grahic Jump Location
Fig. 2

SEM image of ceria samples: (a) 3DOM ceria before and (b) after thermochemical cycling; (c) sintered ceria of porosity 0.08 (dense ceramics); (d) sintered ceria of porosity 0.72 (porous ceramics)

Grahic Jump Location
Fig. 3

Schematic of the problem setup for the identification procedure. For the discrete ordinate method, the domain is assumed to be one-dimensional; for the MCRT simulations, boundary conditions for top, bottom and lateral walls are set according to this schematic.

Grahic Jump Location
Fig. 4

Spectral normal-hemispherical (a) transmittance and (b) reflectance of the 3DOM ceria packed bed in the windowed sample holder obtained experimentally for three selected values of the packed bed thickness

Grahic Jump Location
Fig. 5

Spectral absorption coefficient of 3DOM ceria packed bed identified by discrete ordinate method (lines) and MCRT technique (data points; squares: L = 0.57 mm; circles: L = 1.19 mm; diamonds: L = 1.81 mm)

Grahic Jump Location
Fig. 6

Spectral transport scattering coefficient of 3DOM ceria packed bed identified by discrete ordinate method (lines) and MCRT technique (points; squares: L = 0.57 mm; circles: L = 1.19 mm; diamonds: L = 1.81 mm)

Grahic Jump Location
Fig. 7

Normal–hemispherical (a) transmittance and (b) reflectance of the 3DOM ceria packed bed in the windowed sample holder predicted by the discrete ordinate method (points) and measured experimentally (lines) for three selected values of the packed bed thickness

Grahic Jump Location
Fig. 8

Spectral normal–hemispherical transmittance and reflectance of the 3DOM ceria packed bed in the windowed sample holder for packed bed thickness of 0.57 mm before and after thermochemical cycling

Grahic Jump Location
Fig. 9

Absorption coefficient of 3DOM ceria packed bed before and after thermochemical cycling. Also shown is the absorption coefficient of sintered ceria ceramics with porosity of 0.08 (dense) and 0.72 (porous).

Grahic Jump Location
Fig. 10

Transport scattering coefficient of 3DOM ceria packed bed before and after thermochemical cycling. Also shown is the transport scattering coefficient of sintered ceria ceramics with porosity of 0.08 (dense) and 0.72 (porous).

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In