Abstract
We demonstrate that the so-called pancake bounce of millimetric water droplets
on surfaces patterned with hydrophobic posts (Liu et al 2014 Nat. Phys.
10 515) can be reproduced on larger scales. In our experiment, a bed of nails
plays the role of the structured surface and a water balloon models the water
droplet. The macroscopic version largely reproduces the features of the
microscopic experiment, including the Weber number dependence and the
reduced contact time for pancake bouncing. The scalability of the experiment
confirms the mechanisms of pancake bouncing, and allows us to measure the
force exerted on the surface during the bounce. The experiment is simple and
inexpensive and is an example where front-line research is accessible to student
projects.
on surfaces patterned with hydrophobic posts (Liu et al 2014 Nat. Phys.
10 515) can be reproduced on larger scales. In our experiment, a bed of nails
plays the role of the structured surface and a water balloon models the water
droplet. The macroscopic version largely reproduces the features of the
microscopic experiment, including the Weber number dependence and the
reduced contact time for pancake bouncing. The scalability of the experiment
confirms the mechanisms of pancake bouncing, and allows us to measure the
force exerted on the surface during the bounce. The experiment is simple and
inexpensive and is an example where front-line research is accessible to student
projects.
| Original language | English |
|---|---|
| Article number | 015006 |
| Journal | European Journal of Physics |
| Volume | 38 |
| Issue number | 1 |
| Number of pages | 10 |
| ISSN | 0143-0807 |
| DOIs | |
| Publication status | Published - 2017 |
Keywords
- Weber number
- contact time
- surface tension
- water balloons