The high utilization of the melting space for the bubble removal processes asks for the detailed examination of fining space geometry and glass flow character inside the space. The relative significance of the space utilization for fining may be assessed from simplified models of bubble removal from fining spaces. This work demonstrates how the temperature distribution and resulting glass flow patterns in the simple melting space (horizontal channel) affect the character of bubble removal from the melt due to variable utilization of the space for the process. In performed calculations, the fining performance of the channel producing no bubble defects is the followed technological quantity. The experimentally measured bubble growth rates in the TV model glass were used to evaluate the fining process. To appreciate the impact of glass flow character on the fining efficiency, the numerical model (Glass furnace model – Glass Service, Inc.) was applied, providing the temperature and melt velocity fields, as well as bubble pathways in the channel under given temperature boundary conditions. The results have shown that the character of glass melt flow and the space utilization from the point of view of the bubble removal process may be described by two quantities: the virtual height of bubble rising (the height which the bubble has to rise against downward glass melt flow to the level) and the virtual fraction of dead space for the bubble removal process (the space ineffective for the removal of the critical bubble). The results are intended to assist in developing new concepts of industrial fining spaces.
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