Contact angle of a hemispherical bubble: An analytical approach

JOURNAL OF COLLOID AND INTERFACE SCIENCE

卷:338

Article

Teixeira, M. A. C.²  Teixeira, P. I. C.^1,3 

[1] Univ Lisbon, Ctr Fis Teor & Computac, P-1649003 Lisbon, Portugal

[2] Univ Lisbon, CGUL, IDL, P-1749016 Lisbon, Portugal

[3] Inst Super Engn Lisboa, P-1950062 Lisbon, Portugal

关键词: Foams and emulsions;    Contact lines;   

DOI  :  10.1016/j.jcis.2009.05.062

来源: Elsevier

【 摘 要 】

We have calculated the equilibrium shape of the axially symmetric Plateau border along which a spherical bubble contacts a flat wall, by analytically integrating Laplace's equation in the presence of gravity, in the limit of small Plateau border sizes. This method has the advantage that it provides closed-form expressions for the positions and orientations of the Plateau border surfaces. Results are in very good overall agreement with those obtained from a numerical solution procedure, and are consistent with experimental data. In particular we find that the effect of gravity on Plateau border shape is relatively small for typical bubble sizes, leading to a widening of the Plateau border for sessile bubbles and to a narrowing for pendant bubbles. The contact angle of the bubble is found to depend even more weakly on gravity. (C) 2009 Elsevier Inc. All rights reserved.

【 授权许可】

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