Identification method for infrared absorption spectra of semitransparent media by their emission data Application to lime-aluminosilicate glasses at high temperatures

Abstract

The infrared absorption spectra of four Ume-aluminosihcate glasses have been studied at high temperatures in the spectral range 1 to 5 µm. The glass composition varies essentially by the FeO content. The effect of temperature is pointed out up to 1450 °C. The emission spectrometry technique used is appHed to thin slabs of semitransparent materials heated in plane-parallel platinum crucibles exposed to strong temperature gradients. The absorption coefficient is identified, for each wavelength, by a non-linear constraint optimization technique. As an illustration of the major influence of the spectrum on the heat exchanges in semitransparent devices, a modeling of the combined conductive/radiative heat transfer is performed in a glass wall.