Minimization of the N2 Dilution When Wiping in Air
(Room 310)
07 May 19
11:00 AM
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11:30 AM
Nitrogen wiping is a well-known technology to improve the surface quality of exposed sheet, especially the aspects of waviness and cloudiness. A steady-state computational fluid dynamics (CFD) approach is undertaken — including various gas flows, nozzle-to-strip distances, gas and ambient temperatures, and nozzle design — and computes the oxygen profile at the sheet. The impact of gas viscosity is also investigated. It turns out that the best N2 efficiency is obtained when the ratio of wiping distance to nozzle opening is low. The nozzle design has some impact, whereas that of the gas temperature is minor.