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Search / Korean Journal of Chemical Engineering
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Korean Chemical Engineering Research, Vol.49, No.3, 314-319, 2011
Slot 코팅 공정에서 Non-Newtonian 유체의 코팅 균일성을 위한 최적 다이 설계
An Optimal Die Design for the Coating Uniformity of Non-Newtonian Liquids in Slot Coating Process
본 연구에서는 전산유체모사기인 Fluent를 활용하여 slot 다이 내부에서 Newtonian과 non-Newtonian 코팅액의 동적 거동을 고찰함으로써 최적 다이 설계를 위한 방법론을 구축하고자 하였다. 다이 출구에서 코팅액의 속도분포를 일정하게 하기 위해 chamber 구조를 변화시킴으로써 최적 하이브리드 다이의 설계가 가능하였다. 특히, non-Newtonian 유체의 경우, 전단담화 정도와 chamber의 coat-hanger 최적 길이의 상관관계를 도출하였다.
In this study, the flow behavior of Newtonian and non-Newtonian coating liquids inside slot die has been scrutinized for the purpose of optimal internal die design in slot coating system from three-dimensional computations by CFD Fluent solver. A hybrid slot die could be optimally designed by changing the chamber or manifold structure to guarantee the uniform velocity distribution of coating liquids at die exit. Especially, for the non-Newtonian coating liquids,
the length of coat-hanger for the uniform coating has been properly chosen, according to the degree of their shearthinning properties.
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[Cited By]
- Jin GL, Ahn WG, Kim SJ, Nam J, Jung HW, Hyun JC, Korea-Australia Rheology Journal, 28(2), 159, 2016
- Yoo JH, Choi SW, Ahn KH, Ph JS, Korean Chemical Engineering Research, 55(4), 561, 2017
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