Korea-Australia Rheology Journal

The Korean Society of Rheology (한국유변학회)
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Simplified modeling of slide-fed curtain coating flow

  • Jung Hyun Wook (Department of Chemical and Biological Engineering, Korea University) ;
  • Lee Joo Sung (Department of Chemical and Biological Engineering, Korea University) ;
  • Hyun Jae Chun (Department of Chemical and Biological Engineering, Korea University) ;
  • Kim See Jo (Department of Mechanical Engineering, Andong National University) ;
  • Scriven L. E. (Department of Chemical Engineering and Materials Science, University of Minnesota)
  • Published : 2004.12.01
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Abstract

Simplified model of slide-fed curtain coating flow has been developed and tested in this study. It rests on the sheet profile equations for curtain thickness in curtain flow and its trajectory derived by the integral momentum balance approach of Higgins and Scriven (1979) and Kistler (1983). It also draws on the film profile equation of film thickness variation in flow down a slide. The equations have been solved in finite difference approximation by Newton iteration with continuation. The results show that how inertia (Rey­nolds number), surface tension (capillary number), inclination angle of the slide, and air pressure difference across the curtain affect sheet trajectory and thickness profile. It has been revealed that approximate models can be useful to easily analyze coating flow dynamics without complex computations, giving qualitative agreement with full theory and with experiment.

Keywords

References

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