Capillary Forces between Submillimeter Spheres and Flat Surfaces at Constant Liquid Volumes  

作　　者：王乐锋 荣伟彬 孙立宁 陈立国 邵兵 

机构地区：[1]State Key Laboratory of Robotics and System, Harbin Institute of Technology, Harbin 150080

出　　处：《Chinese Physics Letters》2009年第12期198-201,共4页中国物理快报（英文版）

基　　金：Supported by the National Natural Science Funds for Distinguished Young Scholar under Grant No 50725518, the National Natural Science Foundation of China under Grant Nos 50805040 and 50605013, Self-Planned Task of State Key Laboratory of Robotics and System （HIT） under Grant No SKLRS200804B.

摘　　要：We investigate the capillary forces between submillimeter spheres and flat surfaces at constant liquid volumes theoretically and experimentally. An iterative method is used to estimate the capillary force with contact angles as the boundary conditions and the constant volume as a constraint. The theoretical analysis shows that the maximum capillary force between them decreases with the increase of the liquid bridge volume at small contact angles. The experimental results show that the force is smaller than the theoretical values at the initial separation distances. It is also observed that the force first increases and then decreases with an increasing separation distance in some cases. These phenomena of capillary forces hysteresis are explained according to the wetting hysteresis.We investigate the capillary forces between submillimeter spheres and flat surfaces at constant liquid volumes theoretically and experimentally. An iterative method is used to estimate the capillary force with contact angles as the boundary conditions and the constant volume as a constraint. The theoretical analysis shows that the maximum capillary force between them decreases with the increase of the liquid bridge volume at small contact angles. The experimental results show that the force is smaller than the theoretical values at the initial separation distances. It is also observed that the force first increases and then decreases with an increasing separation distance in some cases. These phenomena of capillary forces hysteresis are explained according to the wetting hysteresis.

关 键 词：Soft matter liquids and polymers Surfaces interfaces and thin films 

分 类 号：TE122.1[石油与天然气工程—油气勘探] TP701[自动化与计算机技术—检测技术与自动化装置]