Radiation characteristics of glass foams

This paper is concerned with the analysis of the radiative heat transfer in glass foams. The closed-form analytical model for the reflectance, transmi ttance, and absorptance of radiation by a foam layer has been utilized to a ssess the resistance of radiation heat transfer from the hot combustion gas es and refractories to the molten glass in the glassmelting furnace due to glass foaming. The size (radius) and shape (void fraction) of foam bubbles, their size distribution function, the scattering anisotropy, and the refle ctance of the foam/glass interface have been identified as major physical p arameters governing the problem. Detailed parametric calculations have been performed, and the results are reported and critically discussed with the aim of quantifying the radiation characteristics of glass foams. The findin gs lead to a fundamental understanding of the radiative transport in the fo ams, and can be used to improve the design and operation of modern glassmel ting furnaces.