Capillary Motion of Floating Bodies

Overview

In this project, we study the motion of flexible floating bodies under the influence of capillary forces.

The motion of rigid bodies has been long-studied and is embodied in the so-called "Cheerios Effect."

This basic effect has been proposed by many researchers as a method for self-assembly.

Some cool Java applets on self-assembly techniques related to this question can be found:

http://xeon.concord.org:8080/modeler/webstart/nano/index.html

Another very cool web page dealing with capillary motion of flexible bodies is:

http://www.damtp.cam.ac.uk/user/dv211/rods.html

Cheerios Effect: 

Bubbles trapped at the interface of a liquid and gas hardly rest. When contained, they tend to clump together in the center, some others will move toward the exterior wall. This phenomenon  takes place in a short period of time, from a few seconds to minutes. This phenomenon has been studied and explained as the "Cheerio Effect."

The long-lived bubbles are trapped at the interface and balanced by the gravity and the buoyancy force. Thus they would move along the meniscus toward the exterior wall.

Capillary Surface between two infinite vertical plates:

• Ordinary Differential Equation Approach
• Energy Approach

Capillary Surface Between One Rigid Wall and One Flexible Wall

• Problem Solving
• Experiment of a Rigid Wall and one Single Rod
• Experiment of a Rigid Wall and a Flexible Wall

Appendix:

• Euler- Lagrange Equation
• Mini Symposium: presentation.ppt