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Stability of two-layer stratified flow in inclined channels: applications to air entrainment in coating systems

Published online by Cambridge University Press:  26 April 2006

Yuan C. Severtson  and
Cyrus K. Aidun
Yuan C. Severtson
Affiliation:
Institute of Paper Science and Technology and The George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, 500 10th Street, N.W. Atlanta, GA 30318-5794, USA
Cyrus K. Aidun
Affiliation:
Institute of Paper Science and Technology and The George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, 500 10th Street, N.W. Atlanta, GA 30318-5794, USA
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Abstract

To understand the physics of air entrainment in thin-film liquid coating and other applications, the stability characteristics of general stratified two-layer Poiseuille-Couette flow are examined in inclined channels. Only one mode of instability, the interfacial mode, is obtained in the long-wave asymptotic limit. The generalized eigenvalue problem, formed by spectral decomposition and solution of the general two-layer Orr-Sommerfeld equation, is solved to obtain all of the critical modes. Analysis of the air/liquid interface corresponding to experiments reveals that because of the large density variation between the two layers, the interfacial mode is the only mode of instability in air entrainment. Results from the stability analysis of the flow near the contact line where air entrainment occurs are consistent with previous experimental observations.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 312 , 10 April 1996 , pp. 173 - 200
Copyright
© 1996 Cambridge University Press

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