Mathematical modeling of cold cap

Journal Article · Sat Oct 13 00:00:00 EDT 2012 · Journal of Nuclear Materials, 429(1-3):245-256

DOI:https://doi.org/10.1016/j.jnucmat.2012.06.013· OSTI ID:1056759

Pokorny, Richard; Hrma, Pavel R

The ultimate goal of studies of cold cap behavior in glass melters is to increase the rate of glass processing in an energy-efficient manner. Regrettably, mathematical models, which are ideal tools for assessing the responses of melters to process parameters, have not paid adequate attention to the cold cap. In this study, we consider a cold cap resting on a pool of molten glass from which it receives a steady heat flux while temperature, velocity, and extent of conversion are functions of the position along the vertical coordinate. A one-dimensional (1D) mathematical model simulates this process by solving the differential equations for mass and energy balances with appropriate boundary conditions and constitutive relationships for material properties. The sensitivity analyses on the effects of incoming heat fluxes to the cold cap through its lower and upper boundaries show that the cold cap thickness increases as the heat flux from above increases, and decreases as the total heat flux increases. We also discuss the effects of foam, originating from batch reactions and from redox reactions in molten glass and argue that models must represent the foam layer to achieve a reliable prediction of the melting rate as a function of feed properties and melter conditions.

• Research Organization: Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1056759
• Report Number(s): PNNL-SA-81395; 830403000
• Journal Information: Journal of Nuclear Materials, 429(1-3):245-256, Journal Name: Journal of Nuclear Materials, 429(1-3):245-256
• Country of Publication: United States
• Language: English