In automotive windshield production, glass pieces held in position with a steel frame ride through the furnace on rollers while being heated by electric coils from the top and bottom. Spectral radiation through the semi-transparent glass medium, coupled with convection and conduction, heats the glass. Dr. Philip Burnside of PPG Industries, Inc. used the newly implemented Discrete Ordinates Model (DOM) in FLUENT 5 to simulate the heating of glass within a furnace. DOM includes the ability to handle semi-transparency and spectral radiation.

Steady and transient 2-D and 3-D calculations were performed to simulate a stationary piece of glass on a frame and a continuous sheet of glass moving through a furnace. The temperature calculations from FLUENT 5 were validated experimentally for different sets of process conditions and were within a few degrees of the measured values for both the stationary and continuous sheet.

Temperature contours of a continuous glass sheet in a furnace with two heating zones. FLUENT 5 predictions were within a few degrees of measured values.

Courtesy of PPG.