Fluid Dynamics Research Group, Curtin University, GPO Box U1987, Perth, Western Australia 6845, Australia.
Langmuir. 2012 Feb 21;28(7):3483-8. doi: 10.1021/la2046838. Epub 2012 Feb 7.
Phobic droplet-fiber systems possess complex geometries, which have made full characterization of such systems difficult. This work has used atomic force microscopy (AFM) to measure droplet-fiber forces for oil droplets on oleophobic fibers over a range of fiber diameters. The work adapted a previous method and a theoretical model developed by the authors for philic droplet-fiber systems. A Bayesian statistical model was also used to account for the influence of surface roughness on the droplet-fiber force. In general, it has been found that the force required to move a liquid droplet along an oleophobic filter fiber will be less than that required to move a droplet along an oleophilic fiber. However, because of the effects of pinning and/or wetting behavior, this difference may be less than would otherwise be expected. Droplets with a greater contact angle (~110°) were observed to roll along the fiber, whereas droplets with a lesser contact angle (<90°) would slide.
疏液滴-纤维体系具有复杂的几何形状，这使得对这类体系的全面描述变得困难。本工作采用原子力显微镜（AFM）测量了一系列纤维直径下，疏油纤维上油滴的纤维-液滴相互作用力。该工作改进了作者先前为亲液滴-纤维体系开发的方法和理论模型。同时，还使用了贝叶斯统计模型来解释表面粗糙度对纤维-液滴力的影响。总的来说，发现沿疏油过滤纤维移动液滴所需的力小于沿亲油纤维移动液滴所需的力。然而，由于钉扎和/或润湿行为的影响，这种差异可能小于预期。观察到接触角较大（约 110°）的液滴会沿纤维滚动，而接触角较小（<90°）的液滴会滑动。
