Determination of spectral radiative properties of open-cell foam: hemispherical–directional spectral transmittance and directional–directional transmittance measurement
Dominique Baillis, Martin Raynaud, Jean-François Sacadura
Spectral radiative properties (absorption coefficient, scattering coefficient, and phase function) of open-cell carbon foam have been determined experimentally. The identification method uses spectral transmittance and reflectance measurements and a prediction model based on a combination of geometric optics laws and diffraction theory. In the wavelength region 0.2 – 2 mm directional – hemispherical transmittance and reflectance measurements are used, and directional – directional transmittance and reflectance measurements are used in the wavelength region 2 – 15 mm. Radiative properties are determined in the wavelength region from visible to infrared. Two approaches corresponding to two different types of measurements are compared for the determination of radiative properties. Moreover, experiments on a guarded hot-plate device are used to confirm that the proposed model is appropriate to predict the radiative heat transfer in such media.