par Halloin, Véronique ;Wajc, Samuel
Référence Chemical engineering communications, 154, page (59-85)
Publication Publié, 1996
Article révisé par les pairs
Résumé : A forehearth is a shallow channel connecting the glass melting furnace to the gob dispenser in the glass bottles production process. Although the temperature of the molten glass has to decrease by several hundred degrees in the forehearth, the temperature distribution in the outlet section must be uniform. Due to the extremely convoluted character of the flow pattern, it is difficult to suggest the design rules and operational procedures that will ensure this uniformity without resorting to detailed experimental and numerical studies. Using a room temperature physical model, we have simulated the creeping flow of glass in a forehearth. The 3D temperature field and velocity field of the model fluid (silicon oil) were mapped. In particular, the complexity of the flow pattern immediately upstream of the outlet section was revealed, and more generally, the overriding importance of the gravity currents induced by the non uniformity of the temperature (hence density) field came to the fore. Numerical results obtained using a commercial computer code (Fluent) were compared to experimental data; they were used to gain insight in the structure of the non isothermal creeping flow considered here. Finally, three modifications of the channel design, meant to improve the temperature uniformity near the outlet section, were tested experimentally.