CFD in glass industry
CFD has a long tradition in glass industry. The measurement of flow quantities is very difficult and therefore simulation greatly helps to understand, evaluate and optimize all applicable processing steps.
Process steps in the glass industry
Typical process steps in the glass industry are
- stirring the glass in special homogenization systems
- hot forming
- feeding, blowing, pressing, rolling, casting, drawing, floating, spinning, ...
The hot end of a glassworks is where the molten glass is formed, beginning when the batch is fed at a slow controlled rate into the furnace. The furnaces are natural gas or fuel oil fired and operate at temperatures up to 1700°C. The temperature is limited by the quality of the furnace superstructure material and by the glass composition.The molten glass flows from a subducted channel known as the furnace throat into the refiner and forehearth channels. These channels transport the glass to the glass forming area. These channels cool the glass very precisely so that the glass at the forming area is of a uniform and exact temperature.
In glass industry, the function of stirring is to create uniform, homogeneous glass. Stirring equipment operates at high temperatures and under high mechanical stresses, so stirring devices have to be robust and often involve large amounts of platinum or platinum alloys. Although stirrers, stirrer bars, blenders, homogenizers, screw plungers and plunging stirrers currently used are generally effective in operation, reliable and with predictable lifetime, lower cost and improved operational efficiency are main targets for the future.
Glass making processes from containers to tableware to TV glass begin with a droplet (gob) being delivered to the forming machines. In a large measure the success of the entire operation depends upon the uniform quality of the gob.
Depending on the final product a huge number of forming processes are known. For example for glass container currently two primary methods exist - the blow and blow method and the press and blow method. Various processes are available to produce thin flat glass sheets (Floating, Rolling, Overflow-Fusion, FOURCAULT drawing, ASAHI drawing, PITTSBURGH process, Down-Draw process). Depending on the product specifications each process has its pros and cons.
Small articles could be found to each production step at