1. Coalescence-Induced Self-Propulsion of Droplets on Superomniphobic Surfaces
- Author
-
Arun K. Kota, Wei Wang, Hamed Vahabi, Seth Davies, and Joseph M. Mabry
- Subjects
Coalescence (physics) ,Work (thermodynamics) ,Range (particle radiation) ,Materials science ,Thermodynamics ,02 engineering and technology ,Radius ,010402 general chemistry ,021001 nanoscience & nanotechnology ,medicine.disease_cause ,01 natural sciences ,Ohnesorge number ,0104 chemical sciences ,Condensed Matter::Soft Condensed Matter ,Physics::Fluid Dynamics ,Viscosity ,Jumping ,Self propulsion ,medicine ,General Materials Science ,0210 nano-technology - Abstract
We utilized superomniphobic surfaces to systematically investigate the different regimes of coalescence-induced self-propulsion of liquid droplets with a wide range of droplet radii, viscosities, and surface tensions. Our results indicate that the nondimensional jumping velocity Vj* is nearly constant (Vj* ≈ 0.2) in the inertial-capillary regime and decreases in the visco-capillary regime as the Ohnesorge number Oh increases, in agreement with prior work. Within the visco-capillary regime, decreasing the droplet radius R0 results in a more rapid decrease in the nondimensional jumping velocity Vj* compared to increasing the viscosity μ. This is because decreasing the droplet radius R0 increases the inertial-capillary velocity Vic in addition to increasing the Ohnesorge number Oh.
- Published
- 2017