Thermal radiation properties of molten salt (properties of alkali metal carbonates)

Abstract

Thermal radiation properties were investigated by a spectroscopic experiment on three molten alkali metal carbonates: lithium carbonate, sodium carbonate, and potassium carbonate. Reflectance spectra of the salt layers were measured at wavelengths from 0.5 to 13.0 μm. The results were analyzed to obtain the spectra of the refractive index n and absorption coefficient K. Since the semi-transparent wave-length region of the salts was found to range in the main part of the Planckian distribution, the values of K were determined most carefully. The spectra of n and K are described by continuous functions of radiation wavelength for heat-transfer engineering application