Constellation, le dépôt institutionnel de l'Université du Québec à Chicoutimi

Résumé

In the electrical preheat of aluminum reduction cell, deformations and stresses in all components of the cell are principally due to the temperature gradients. The temperature distribution is essentially established by the Joule effect in the electrical conductors. Furthermore, electrical current distribution is strongly dependent on the use of petroleum coke bed, playing the role of electrical resistor, placed between anode and cathode panels. The thermoelectric behavior of the bed is then an important factor on the preheat quality and must be included in a complete cell preheat model. The behavior of granular materials is usually represented by effective properties. However, it was observed experimentally that the contact quality between coke bed and a plane surface like anode blocks has an important effect on the electrical current and temperature distributions. In this respect, both thermal and electrical constitutive laws have to be developed. Constitutive laws parameters are calibrated by comparing experimental data with finite element model results using new contact elements.