TY - JOUR
T1 - Drop impact on hairy surfaces
AU - Nasto, Alice
AU - Brun, P. T.
AU - Hosoi, A. E.
N1 - Funding Information:
A.N. and A.E.H. acknowledge support from the US Army Research Office under Grant No. ARO W911NF-15-1-0166.
Publisher Copyright:
© 2019 American Physical Society.
PY - 2019/6/26
Y1 - 2019/6/26
N2 - We investigate the impact of liquid drops on millimeter-scale hairy surfaces. By varying the speed of the drop, the spacing of the hairs, and the viscosity of the liquid, we observe a variety of behaviors. In some cases, the liquid drop can remain on top of the hair after impact, similar to a Cassie-Baxter superhydrophobic state. If the drop penetrates the hairy surface, the hairs can resist droplet spreading. Using this scenario as a reference case, we rationalize the role of the hairs in dissipating the kinetic energy of the impacting drop through a balance of inertia, viscosity, and surface tension. The various observed behaviors are classified according to scenarios in which kinetic energy is insufficient or in excess of this reference scenario, an argument that allows us to build and rationalize a phase diagram.
AB - We investigate the impact of liquid drops on millimeter-scale hairy surfaces. By varying the speed of the drop, the spacing of the hairs, and the viscosity of the liquid, we observe a variety of behaviors. In some cases, the liquid drop can remain on top of the hair after impact, similar to a Cassie-Baxter superhydrophobic state. If the drop penetrates the hairy surface, the hairs can resist droplet spreading. Using this scenario as a reference case, we rationalize the role of the hairs in dissipating the kinetic energy of the impacting drop through a balance of inertia, viscosity, and surface tension. The various observed behaviors are classified according to scenarios in which kinetic energy is insufficient or in excess of this reference scenario, an argument that allows us to build and rationalize a phase diagram.
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U2 - 10.1103/PhysRevFluids.4.064004
DO - 10.1103/PhysRevFluids.4.064004
M3 - Article
AN - SCOPUS:85073396233
SN - 2469-990X
VL - 4
JO - Physical Review Fluids
JF - Physical Review Fluids
IS - 6
M1 - 064004
ER -