Behaviour of bubble files in glass melting space

Abstract

A calculation model of the bubble concentration field inside a melting space is presented, based on the technique of tracing representative bubbles. The bubbles in the model originated from glass batch and from refractory. The appropriate bubble input values were obtained by laboratory experiments. The impact of various initial and boundary conditions, as well as melting conditions, on the bubble distribution inside the melting space was studied: a) the impact if initial amount of entering bubbles and their size distribution, b) the impact of initial redox state of glass, and c) the influence of bubble history. The results demonstrated the significance of the redox state of glass and the average temperature along bubble trajectories for the fining process. The calculated bubble compositions at the output and bubble histories were used to distinguish the bubbles coming from two bubble sources and to reveal the starting positions of defect bubbles. An attempt was made to estimate the bubble impact on the glass flow and on the redox state of glass using the bubble tracing technique. The preliminary calculations indicated that bubbles influence the melt flow.