SpectralEmissivity & Emittance

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Modeling of the thermal radiative behavior of rough coatings

Abstract 675 – Monte Carlo modeling of the thermal radiative behavior of rough coatings

Presented in the session Photothermal Techniques. Theory and Modeling at the 18th European Conference on Thermophysical Properties, Pau, France 31 Aug-4 Sep 2008
By:
Mr Hector Gomarta*+
Dr Benoit Rousseaua
Dr Domingos De Sousa Menesesa
Dr Patrick Echeguta

a CNRS Orléans
CEMHTI
Site Haute Température
1D avenue de la Recherche Scientifique
45071 cedex 02, France

*: Corresponding author
+: Presenting author

ABSTRACT:

Surface roughness plays a crucial role in the thermal radiative properties of industrial systems, such as infrared heaters, plate near blackbody references used to calibrate a pyrometric setup. Nevertheless literature usually reports radiative properties simulations only for several wavelengths. In this study, we focus on modeling emissivity over a wide IR-spectral range for surfaces either measured by profilometry or numerically rebuild.

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Texture and porosity effects on the thermal radiative behavior of alumina ceramics

Texture and porosity effects on the thermal radiative behavior of alumina ceramics
Int. J. Thermophys. (in press) [view]

New Article
By: O.Rozenbaum, D.De Sousa Meneses; P.Echegut
Texture and porosity effects on the thermal radiative behavior of alumina ceramics
Int. J. Thermophys. (in press) [view]

ABSTRACT
“Thermal and optical properties of ceramics are dependent on radiation scattering and cannot be determined by the only knowledge of their chemical composition as for single crystals. In this paper, we investigate extrinsic effects such as roughness, porosity and texture on spectral emissivity of alumina ceramics. Roughness effects have an influence mainly in the opaque zone; an important porosity dependence and the presence of a critical porosity threshold were also pointed out in the semi-transparent zone. Furthermore, it was shown that two ceramics with similar total porosity but with different textures possess radically different emissivities, showing that grain size, pore size and spatial repartition of the grains is also crucial for the comprehension of the ceramics thermal properties”

Work performed at and reported by: Centre National de la Recherche Scientifique (CNRS), France.