How Can Surface Tension Be Managed to Prevent Water Droplets from Splitting?

[CT_Scientist]

This is an applied physics problem.

A droplet of water sits on a horizontal surface. A large horizontal surface descends on the droplet and squashes it. The surface moves upwards; droplet is unsquashed. Further movement causes the drop to stretch towards the moving surface. At some point, the moving surface tears off a small hunk of water and makes it own droplet. The surface energy of the moving surface is 23 dynes/in.

Is this phenomnon typical? How can I fix this...meaning no water remaining of the moving surface.

 

[LightHero]

Yes, this phenomenon is typical. The key to preventing any water droplet from sticking to the moving surface is to ensure that the surface energy of the moving surface is higher than the surface energy of the water droplet. This can be achieved by making sure that the moving surface has a high enough surface energy; try using a surface with a surface energy of at least 30 dynes/in. Additionally, you can also apply a coating or lubricant to the surface to increase its surface energy and reduce the attraction between the two surfaces.

 

[charng]

I would approach this problem by first understanding the concept of surface tension. Surface tension is the force that causes the surface of a liquid to behave like a stretched elastic membrane. In this scenario, the droplet of water is held together by the cohesive forces of surface tension, while the descending surface exerts a disruptive force that overcomes the cohesive forces and causes the droplet to stretch and eventually break apart.

This phenomenon is indeed typical and can be observed in various situations, such as when a raindrop falls onto a body of water or when a bubble pops. To prevent this from happening, we need to minimize the surface energy of the moving surface, which can be achieved by using materials with lower surface energy or by altering the surface properties through various methods such as coating or surfactants.

Another approach could be to modify the shape or speed of the descending surface to reduce the disruptive force it exerts on the droplet. Additionally, controlling the angle at which the surface descends onto the droplet can also play a role in minimizing the disruptive force and preventing the droplet from breaking apart.

In summary, this is an applied physics problem that can be solved by understanding the principles of surface tension and applying various techniques to minimize the disruptive forces and maintain the integrity of the droplet. With further research and experimentation, we can develop more effective methods to prevent water from remaining on the moving surface.