Effect of heating rate on glass foaming: Transition to bulk foam

Glass fining has an undesirable side effect: glass foaming. In a recent experimental study, the foam volume responded dramatically when the rate of temperature-increase varied from 5 to 15 °C/min. This observation indicates that an enhanced temperature-increase rate (a natural consequence of the increased processing rate experienced as a result of the transition to oxy-fuel firing) may exert a substantial influence on glass foaming in advanced glass-melting furnaces. This paper attributes this effect to the change of mode of foam formation as a response to an increased rate of heating.