Physical Modeling of Electric Glass-Melting Furnaces for High-Level-Waste Immobilization

摘要

Physical models have been developed to investigate thermophysical processs in electric glass melting furnaces and to assist with the development of alternative designs. The models were constructed of transparent plexiglass with water cooled surfaces to simulate the boundary conditions in the prototype. The experiments were designed to maintain equality of the Rayleigh, Peclet, and Nusselt numbers and a dimensionless source term. Models with two different length/width/depth ratios have been tested using segmented bar and plate type electrodes. The model fluids were solutions of 7.5% LiCl in glycerine. Fluid velocities were determined from multiple exposure and streak photographs of particles added to the fluid as tracers. The results show that the bulk of the fluid was essentially isothermal with flow patterns that were dominated by two large but indistinct counter-rotating cells. Within each cell the flow was chaotic with no stable structure. Although the results to date have been primarily qualitative, they have been useful in understanding the glass melting processes in the furnaces.