Determination of spectral radiative properties of open cell foam: Model validation

Spectral radiative properties (absorption coefficient, scattering coefficie nt, and phase function) of open cell carbon foam are determined experimenta lly. The identification method uses spectral transmittance and reflectance measurements and a prediction model based on a combination of geometric opt ics laws and of diffraction theory. In the wavelength region of 0.1-2.1 mu m, directional-hemispherical transmittance and reflectance measurements are used, whereas directional-directional transmittance and reflectance measur ements are used in the wavelength region of 2-15 mu m. Thus, radiative prop erties are determined in the wavelength region from visible to infrared. Th e two approaches corresponding to the two different types of measurement (d irectional-directional and directional-hemispherical) are compared for the determination of radiative properties. Moreover, experiments performed on a guarded hot-plate-type device are used to confirm that the proposed model is appropriate to predict the radiative heat transfer in such media.