Home Practical Limitations to Carrier Layer Formation on Inclined Planes
Article
Licensed
Unlicensed Requires Authentication

Practical Limitations to Carrier Layer Formation on Inclined Planes

  • J. B. Ikin , H. M. Thompson , P. H. Gaskell and C. J. Noakes
Published/Copyright: March 26, 2013
Become an author with De Gruyter Brill
Submit Manuscript Author Information
International Polymer Processing
From the journal International Polymer Processing Volume 22 Issue 1

Abstract

Two important instabilities associated with carrier layer formation on the inclined plane of slide-fed coating processes are explored, with a two liquid layer prototype configuration employed to mimic the slide-bead process as used by industry. The work relates to both slide-bead and curtain coating methods. Experiments first reveal how broad diffuse bands, that destroy the quality of the final coating, are formed as the carrier layer flow rate is reduced. The bands are found to be exacerbated by either decreasing the viscosity or flow rate of the carrier layer or by increasing the viscosity of the upper layer. As the flow rate of the carrier layer is reduced further, the upper layer begins to invade the carrier layer delivery slot. Flow visualisations reveal that a parallel sided delivery slot is superior to a chamfered one in terms of robustness against invasion of the interface and that reducing the slot width increases robustness further. Experiments and complementary numerical simulations confirm the existence of a recirculating eddy near the top of the downstream wall as the carrier layer flow rate is reduced and this insight is used to propose an instability mechanism for the onset of the bands. Further experiments expose the mechanism for the formation of cross bars. These can develop downstream of the carrier layer delivery slot and arise because the merging of the layers there becomes increasingly influenced by the flow, demonstrating that the sensitivity of cross bars to pump induced disturbances grows rapidly as the critical carrier layer flow rate for instability is approached and then collapses as the flow rate is reduced to a value where the layer is no longer effective in lubricating the flow of adjacent layers.

∗ Mail address: H. M. Thompson, School of Mechanical Engineering, University of Leeds, Blenhem Terrace, Leeds, West Yorkshire, LS2 9JT, UK. E-mail:

References

1Gaskell, P. H., Thompson, H. M., Savage, M. D., Ikin, J. B.: Chem. Eng. Sci. 56, p. 4627 (1999)Search in Google Scholar

2Noakes, C. J., Gaskell, P. H., Thompson, H. M., Ikin, J. B.: Trans IChemE80(A), p. 449 (2002)10.1205/026387602320224030Search in Google Scholar

3US Patent 4001024 (1977) Dittman, D. A., Rozzi, A.Search in Google Scholar

4Schweizer, P. M., Rossier, P.-A.: Proceeding 4th Eur. Coat. Symp., p. 263 (2001)Search in Google Scholar

5Ikin, J. B., Gaskell, P. H., Noakes, C. J., Thompson, H. M.: Proceeding 4th Eur. Coat. Symp., p. 277 (2001)Search in Google Scholar

6US Patent 4283443 (1981) Choinski, E. J.Search in Google Scholar

7Ikin, J. B., Gaskell, P. H., Thompson, H. M.: Proceeding 5th Eur. Coat. Symp., p. 190 (2003)Search in Google Scholar

8Ikin, J. B.: Ph.D. Thesis, University of Leeds, (2005)Search in Google Scholar

9Christodoulou, K. N.: PhD Thesis, University of Minnesota, Minneapolis (1990)Search in Google Scholar

10Schweizer, P. M., Rossier, P.-A.: Proceeding 5th Eur. Coat. Symp., p. 182 (2003)Search in Google Scholar

11Valentini, J. E., Thomas, W. R., Sevenhuysen, P., Jiang, T. S., Lee, H. O., Liu, Y., Yen, S. C.: Ind. Eng. Chem. Res. 30, p. 453 (1991)10.1021/ie00051a004Search in Google Scholar

12US Patent 4041897 (1978) Ade, F.Search in Google Scholar

13Apps, C. J.: Ph.D. Thesis, University of Leeds (2000)Search in Google Scholar

14US Patent 5376401 (1994) Conroy, J. E., Weinstein, S. J.Search in Google Scholar

Received: 2006-5-5
Accepted: 2006-11-20
Published Online: 2013-03-26
Published in Print: 2007-03-01

© 2007, Carl Hanser Verlag, Munich

Articles in the same Issue

  1. Contents
  2. Contents
  3. Editorial
  4. International Polymer Processing Special Issue: European Coating Symposium 2005, University of Bradford, UK
  5. Invited Papers
  6. Coating and Polymer Processing
  7. Practical Limitations to Carrier Layer Formation on Inclined Planes
  8. Simulation of 3D Crystallization of Colloidal Nanoparticles on a Substrate during Drying
  9. Asymmetric Surface Roughness Formationon Moving Non-isothermal Liquid Coatings
  10. Inkjet Printing of Conductive and Resistive Coatings
  11. Moisture Sorption and Transport in Polylactide
  12. 10.3139/217.0992
  13. Review Article
  14. Welding of Plastics: Fundamentals and New Developments
  15. Regular Contributed Articles
  16. Numerical Simulation of Viscous Flow in a Partially filled Co-rotating Twin Screw Extruder
  17. Invited Papers
  18. A New Calculation Model and Optimization Method for Maddock Mixers in Single Screw Plasticising Technology
  19. Regular Contributed Articles
  20. Residual Wall Thickness Distribution at the Transition and Curve Sections of Water-assisted Injection Molded Tubes
  21. Numerical Simulation of Extrusion Coating
  22. Correlation between Injection Molding Parameters, Morphology and Mechanical Properties of PPS/SEBS Blend Using Artificial Neural Networks
  23. PPS News
  24. PPS News
  25. Seikei-Kakou Abstracts
  26. Seikei-Kakou Abstracts
https://doi.org/10.3139/217.0053

Articles in the same Issue

  1. Contents
  2. Contents
  3. Editorial
  4. International Polymer Processing Special Issue: European Coating Symposium 2005, University of Bradford, UK
  5. Invited Papers
  6. Coating and Polymer Processing
  7. Practical Limitations to Carrier Layer Formation on Inclined Planes
  8. Simulation of 3D Crystallization of Colloidal Nanoparticles on a Substrate during Drying
  9. Asymmetric Surface Roughness Formationon Moving Non-isothermal Liquid Coatings
  10. Inkjet Printing of Conductive and Resistive Coatings
  11. Moisture Sorption and Transport in Polylactide
  12. 10.3139/217.0992
  13. Review Article
  14. Welding of Plastics: Fundamentals and New Developments
  15. Regular Contributed Articles
  16. Numerical Simulation of Viscous Flow in a Partially filled Co-rotating Twin Screw Extruder
  17. Invited Papers
  18. A New Calculation Model and Optimization Method for Maddock Mixers in Single Screw Plasticising Technology
  19. Regular Contributed Articles
  20. Residual Wall Thickness Distribution at the Transition and Curve Sections of Water-assisted Injection Molded Tubes
  21. Numerical Simulation of Extrusion Coating
  22. Correlation between Injection Molding Parameters, Morphology and Mechanical Properties of PPS/SEBS Blend Using Artificial Neural Networks
  23. PPS News
  24. PPS News
  25. Seikei-Kakou Abstracts
  26. Seikei-Kakou Abstracts
Sign up now to receive a 20% welcome discount
Institutional Access
How does access work?
Have an idea on how to improve our website?
Please write us.
© 2025 De Gruyter Brill
Downloaded on 7.9.2025 from https://www.degruyterbrill.com/document/doi/10.3139/217.0053/pdf
Scroll to top button