Generalized Cassie-Baxter equation for wetting of a spherical droplet within a smooth and heterogeneous conical cavity

Long Zhou, Guang-Hua Sun, Kai-Hui Zhao, Xiao-Song Wang, Ai-Jun Hu


Introducing the concepts of both Gibbs’s dividing surface and Rusanov’s dividing line, the wettability behaviors of spherical drops inside a smooth and heterogeneous conical cavity are studied. A new generalized Cassie-Baxter equation for contact angles including the influences of the line tension is derived thermodynamically. Additionally, various approximate formulae of this generalized Cassie-Baxter equation are also discussed correspondingly under some assumptions.


Contact angle; Generalized Cassie-Baxter equation; Line tension; Dividing surface

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