Stability of Film Blowing

Han and Park (1975c) experimentally studied flow instabilities in film blowing by introducing disturbances in the air overpressure or the take-up speed. They found that HDPE and LDPE are more sensitive to take-up speed disturbances 

FIGURE 9.26 Typical bubble instability shapes. (Reprinted by permission of the publisher from Kanai and White, 1984.) 

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