Development of simulation model for cold-cap of TVF glass melter

Asahi, Yoshimitsu; Kodaka, Akira

In the glass production of TVF melter, as raw material, fiberglass frit cartridges saturated with HAW are supplied to the melter. A lot of in-melting cartridges float on the molten glass surface and form a layer called cold-cap. A simulation model of the cold-cap, which enables reproduction of temperature distribution was developed. The cold-cap was modeled as a two-phase flow of cartridges and molten glass with fluid-particle interaction. The increasing of the apparent viscosity and the decreasing of joule heat current and thermal conductivity caused by floating cartridges are defined as a function of the concentration of solid particles. By involving these models simultaneously, a simulation in regard to an operation during glass production for the 2nd melter in TVF yields a slow fluid velocity at the cold-cap region and reproduced a thermally isolated layer, and the change of temperature observed at the bottom side of the cold-cap.