In electrically heated glass melters, favorable convection patterns may mitigate gas layer buildup under the unmelted "cold cap", enhance heat transfer to the batch, and possibly accelerate batch reactions, thereby increasing melt rate and glass throughput. Favorable control of convection patterns may also improve homogenization, avoid cold spots, and provide other operational benefits. Convective patterns in an electrically heated melter are strongly influenced by Joule heat distribution and thermal boundary conditions for a given melter design and geometry. Electrical driving control, in particular, interactive control of electrical potentials connected to distinct electrode pairs, can be used to vary the Joule heat generation. One parameter affecting the Joule heat distribution is the "overlap" of the driving voltages waveforms. The "overlap" due to harmonic driving is determined by the relative phase. For electrical driving using waveforms chopped by Silicon Controlled Rectifiers (SCRs), the chopping influences the "overlap." Our study demonstrates with a model that tailored electrical driving is a means to control heat distribution and convection patterns in joule-heated waste glass melters.
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