Some problems of precise measurements of heat transfer coefficients in glass melts : Part 1. Measurements of effective conductivity

Abstract

In the paper the method of measurements of the so-called effective conductivity of glass melts basing on characteristic of temperature gradient in a molten glass inside a refractory tank is analyzed. For this purpose a computer model based on the solution of the radiative transfer equation in a semitransparent medium was used. Among the papers on effective conductivity measurements published so far, only two contained enough numerical information on the details of measurement which permitted to perform the corresponding calculations. The authors of the present paper show what particular defects of experimental procedure could be the reason of surprising results reported in these publications, namely that the measured effective conductivity coefficient of a number of glasses was found to be lower than the radiative conductivity alone