TOWARD COMPUTATIONAL MODELS OF ARC DYNAMICS IN SILICON SMELTERS

Abstract

The production of silicon in electric smelting furnaces is a complex and energy-intensive process. High current plasma arcs are used in such furnaces to generate the temperatures required for the chemical reaction of silica to silicon. In order to facilitate further study of such processes, a computational magnetohydrodynamic model suitable for studying the electrical and dynamic behaviour of alternating current plasma arcs at industrial scales is described. An implementation of the model in the OpenFOAM® computational mechanics framework is developed, tested, and validated. A simulation workflow for prediction of practical aspects of furnace operation is demonstrated with a simple example calculation of the dependence of electrical parameters on electrode position for systems with multiple arcs in the presence of a test gas (Argon). It was found that the nonlinear electrical behaviour of the arc was exaggerated by the presence of multiple arcs, and that control of the furnace’s voltage and current parameters by moving the electrodes could be negatively affected as a result.