CNISM and Department of Physics and Astronomy G. Galilei, University of Padova, Via Marzolo 8, 35131 Padova, Italy.
Phys Rev Lett. 2013 Aug 9;111(6):066101. doi: 10.1103/PhysRevLett.111.066101. Epub 2013 Aug 5.
We present a comprehensive study of water drops sliding down chemically heterogeneous surfaces formed by a periodic pattern of alternating hydrophobic and hydrophilic stripes. Drops are found to undergo a stick-slip motion whose average speed is an order of magnitude smaller than that measured on a homogeneous surface having the same static contact angle. This motion is the result of the periodic deformations of the drop interface when crossing the stripes. Numerical simulations confirm this view and are used to elucidate the principles underlying the experimental observations.
我们对由交替亲水性和疏水性条纹组成的周期性图案形成的化学非均匀表面上的水滴滑动进行了全面研究。发现水滴经历了一种粘滑运动，其平均速度比在具有相同静态接触角的均匀表面上测量的速度小一个数量级。这种运动是当水滴跨越条纹时界面周期性变形的结果。数值模拟证实了这一观点，并用于阐明实验观察结果的原理。
