Some features of the convective movement of molten glass at the hot spot of a flat glass furnace

Abstract

Listen

Translate article

A study of the effect of the heat regime of the furnace on the character of the movement of the glass at the hot spot is difficult since it is necessary to obtain several parameters of the motion of the glass in the internal layers of the melt which is impossible to do in an operational furnace. In order to study the details of these flows in a physical model, we must turn to a larger scale; however, a thick layer of a model liquid sharply degrades the observation conditions. Therefore, it seemed more promising for this purpose to use a mathematical model of the feature of the glass in the hot-spot region. We therefore set ourselves the task of studying the features of the motion of the molten glass at the hot spot and choosing the main parameters which would characterize this motion. In several studies [3, 4], mathematical models have been made which make it possible to calculate the temperature distribution and rate of flow of the glass. Unfortunately, when these models are used, information can only be obtained for two main convection cycles in a glass-melting furnace because of several factors: the complexity of specifying the boundary conditions when solving the heat problems; the lengthy calculations and the relatively rough grid at whose lattic points the relevant parameters are calculated; and the insufficient accuracy in specifying the heat-physics parameters of the glass. It is not possible entirely to avoid these disadvantages. However, in order to eliminate some of them we have now in this study made use of the data on actual temperature fields in the glass (Fig. ]) of real flat glass furnaces; the data were obtained on the basis of heat-engineering measurements (study by L. M. Protsenko, V. S. Pavlov, and V. V. Fokin). For the solution of the system of equations given below, we used computer methodology and algorithms in order to formalize a qualitative description of the production processes using odd powers [5] which makes it possible to obtain a zero approximation. The system of differential equations describing the two-dimensional movement of the glass has the form: OVx + av~ Ox ~ =0;