Capillary-inertial colloidal catapults upon drop coalescence.


Journal Article

Surface energy released upon drop coalescence is known to power the self-propelled jumping of liquid droplets on superhydrophobic solid surfaces, and the jumping droplets can additionally carry colloidal payloads toward self-cleaning. Here, we show that drop coalescence on a spherical particle leads to self-propelled launching of the particle from virtually any solid surface. The main prerequisite is an intermediate wettability of the particle, such that the momentum from the capillary-inertial drop coalescence process can be transferred to the particle. By momentum conservation, the launching velocity of the particle-drop complex is proportional to the capillary-inertial velocity based on the drop radius and to the fraction of the liquid mass in the total mass. The capillary-inertial catapult is not only an alternative mechanism for removing colloidal contaminants, but also a useful model system for studying ballistospore launching.

Full Text

Duke Authors

Cited Authors

  • Chavez, RL; Liu, F; Feng, JJ; Chen, C-H

Published Date

  • July 5, 2016

Published In

Volume / Issue

  • 109 / 1

Start / End Page

  • 011601 -

PubMed ID

  • 27478201

Pubmed Central ID

  • 27478201

Electronic International Standard Serial Number (EISSN)

  • 1077-3118

International Standard Serial Number (ISSN)

  • 0003-6951

Digital Object Identifier (DOI)

  • 10.1063/1.4955085


  • eng