Surface Tension and Electrostriction in a Suspended Bridge of Dielectric Liquid
Yan Cen1, Chuanshan Tian1,2**
1State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433 2Collaborative Innovation Center of Advanced Microstructures, Nanjing 210093
Abstract：The mechanism of the formation of a surprisingly long suspended liquid bridge subjected to a dc electric field has been intensively studied in the past few decades. However, the role of electrostriction and quantitative evaluation of surface tension in the bridge have not been evaluated. We present combined theoretical and experimental studies on this issue. Electrostriction is pointed out to be the driving force that pushes liquid upward against gravity and into the gap between two containers and forms the suspended bridge, which is within the framework of the Maxwell pressure tensor. Through a comparison between experiment and theory, the surface tension is found to play an important role in holding the long suspended bridge. Ignorance of the surface tension leads to much smaller bridge length than the experimental values. The dynamic stability of the bridge with respect to its diameter, length and conductance is also discussed.
2018, Vol. 35 
