Raw data (Wetting angles) from Characterization of interface properties of fluids by evaporation of a capillary bridge

The surface properties between two non-miscible fluids are key elements to understand mass transfer, chemistry and bio-chemistry at interfaces. In this paper, surface properties are investigated in evaporating and non-evaporating conditions. A capillary bridge between two large plates (similarly as a Hele-Shaw cell) is considered. The temporal evolution of surface forces and mass transfers due to evaporation of the liquid are measured. The force depends on surface properties of the substrate. It is adhesive in the wetting case and repulsive in the non-wetting case. The force is also shown to depend linearly on the volume of the capillary bridge <i>F</i> ∝ <i>V</i>₀ and inversely to the height of the bridge. Modelling is performed to characterize both surface force and evaporation properties of the capillary bridge. The evaporation is shown to be diffusion driven and is decoupled from the bridge mechanics.

两种互不相溶流体间的界面性质，是理解界面处传质、化学及生物化学过程的核心要素。本研究针对蒸发与非蒸发工况下的界面性质展开探究，研究体系为两块大平板间形成的毛细桥（capillary bridge），其结构与赫勒-肖槽（Hele-Shaw cell）类似。研究中对液体蒸发引发的表面力随时间的演化过程与传质现象进行了测量。该表面力的大小取决于基底的界面性质：在润湿工况下表现为粘附力，在非润湿工况下则表现为排斥力。研究还发现，表面力与毛细桥的体积<i>V</i>₀呈线性正比关系，且与桥体高度成反比，即<i>F</i> ∝ <i>V</i>₀。本研究通过建模对毛细桥的表面力与蒸发特性进行了表征，结果表明蒸发过程由扩散主导，且与桥体力学行为相互解耦。