Impinging a millimeter-sized liquid droplet on a leaky substrate—such as a porous mesh—can cause the formation of many small droplets from the ligament fragmentation. Although this phenomenon has been widely considered as a desirable strategy to produce liquid sprays of monodisperse droplets, the underlying mechanism has not yet been completely elucidated, and the spray needs detailed characterization. Herein, we experimentally investigate the atomization phenomena occurring in the recoiling and spreading stages of impinging water droplets on superhydrophobic meshes. We show that the spray formed during droplet recoiling is stimulated by the longitudinally symmetric air cavity collapse on the superhydrophobic mesh, and thus the size of the spray formation area on the mesh is almost identical to the size of the simultaneously generated upward jet. By contrast, the water spray produced during droplet spreading is expelled under the action of the inertia-induced hydrodynamic pressure, and the size of spray formation area on the mesh exhibits a power-law dependence on the Weber number; yet, the pore geometry restricts it to take a constant value when the Weber number is sufficiently high. By performing statistical analyses on the spray droplet sizes, we further demonstrate that the mean sizes of spray droplets are mainly set by the mesh pore sizes, but the complex atomization dynamics leads to a broad size distribution, which is beyond the expectation.
References
1.
A. H.
Lefebvre
and V. G.
McDonell
, Atomization and Sprays
(CRC Press
, 2017
).2.
E.
Villermaux
, “Fragmentation
,” Annu. Rev. Fluid Mech.
39
, 419
(2007
).3.
P. H.
Marmottant
and E.
Villermaux
, “On spray formation
,” J. Fluid Mech.
498
, 73
(2004
).4.
G.
Wang
, J.
Gao
, and K. H.
Luo
, “Droplet impacting a superhydrophobic mesh array: Effect of liquid properties
,” Phys. Rev. Fluids
5
, 123605
(2020
).5.
D. H.
Sharp
, “An overview of Rayleigh-Taylor instability
,” Phys. D
12
(3
), 3
(1984
).6.
Lord
Rayleigh
, “On the instability of jets
,” Proc. London Math. Soc.
10
, 4
(1878
).7.
S. T.
Thoroddsen
, K.
Takehara
, T. G.
Etoh
, and C. D.
Ohl
, “Spray and microjets produced by focusing a laser pulse into a hemispherical drop
,” Phys. Fluids
21
, 112101
(2009
).8.
E.
Villermaux
, P.
Marmottant
, and J.
Duplat
, “Ligament-mediated spray formation
,” Phys. Rev. Lett.
92
, 074501
(2004
).9.
B.
Keshavarz
, E. C.
Houze
, J. R.
Moore
, M. R.
Koerner
, and G. H.
McKinley
, “Ligament mediated fragmentation of viscoelastic liquids
,” Phys. Rev. Lett
117
, 154502
(2016
).10.
S.
Kooij
, R.
Sijs
, M. M.
Denn
, E.
Villermaux
, and D.
Bonn
, “What determines the drop size in sprays?
,” Phys. Rev. X
8
, 031019
(2018
).11.
T. D.
Fansler
and S. E.
Parrish
, “Spray measurement technology: Review
,” Meas. Sci. Technol.
26
, 012002
(2015
).12.
J. S.
Li
, “Effect of pressure and nozzle shape on the characteristics of sprinkler droplet spectra
,” J. Agric. Eng. Res
66
, 15
(1997
).13.
A.
Jaworek
and A. T.
Sobczyk
, “Electrospraying route to nanotechnology: An overview
,” J. Electrost.
66
, 197
(2008
).14.
F.
Baillot
, J. B.
Blaisot
, G.
Boisdron
, and C.
Dumouchel
, “Behaviour of an air-assisted jet submitted to a transverse high-frequency acoustic field
,” J. Fluid Mech.
640
, 305
(2009
).15.
S.
Ryu
, P.
Sen
, Y.
Nam
, and C.
Lee
, “Water penetration through a superhydrophobic mesh during a drop impact
,” Phys. Rev. Lett.
118
, 014501
(2017
).16.
D.
Soto
, H. L.
Girard
, A. L.
Helloco
, T.
Binder
, D.
Quéré
, and K. K.
Varanasi
, “Droplet fragmentation using a mesh
,” Phys. Rev. Fluids
3
, 083602
(2018
).17.
S. A.
Kooij
, A. M.
Moqaddam
, T. C. d
Goede
, D.
Derome
, J.
Carmeliet
, N.
Shahidzadeh
, and D.
Bonn
, “Sprays from droplets impacting a mesh
,” J. Fluid Mech.
871
, 489
(2019
).18.
P.
Brunet
, F.
Lapierre
, F.
Zoueshtiagh
, V.
Thomy
, and A.
Merlen
, “To grate a liquid into tiny droplets by its impact on a hydrophobic microgrid
,” Appl. Phys. Lett.
95
, 254102
(2009
).19.
G. N.
Zhang
, M. A.
Quetzeri-Santiago
, C. A.
Stone
, L.
Botto
, and J. R.
Castrejon-Pita
, “Droplet impact dynamics on textiles
,” Soft Matter
14
, 8182
(2018
).20.
C.
Josserand
and S. T.
Thoroddsen
, “Drop Impact on a Solid Surface
,” Annu. Rev. Fluid Mech.
48
, 365
(2016
).21.
A.
Kumar
, A.
Tripathy
, Y.
Nam
, C.
Lee
, and P.
Sen
, “Effect of geometrical parameters on rebound of impacting droplets on leaky superhydrophobic meshes
,” Soft Matter
14
, 1571
(2018
).22.
B.
Pang
, H.
Liu
, P. W.
Liu
, H.
Zhang
, G.
Avramidis
, L. Q.
Chen
, X.
Deng
, W.
Viöl
, and K.
Zhang
, “Robust, easy-cleaning superhydrophobic/superoleophilic copper meshes for oil/water separation under harsh conditions
,” Adv. Mater. Interfaces
6
, 1900158
(2019
).23.
M.
Reyssat
, A.
Pepin
, F.
Marty
, Y.
Chen
, and D.
Quere
, “Bouncing transitions on microtextured materials
,” Europhys. Lett.
74
, 306
(2006
).24.
Y.
Renardy
, S.
Popinet
, L.
Duchemin
, M.
Renardy
, S.
Zaleski
, C.
Josserand
, M. A.
Drumright-Clarke
, D.
Richard
, C.
Clanet
, and D.
Quere
, “Pyramidal and toroidal water drops after impact on a solid surface
,” J. Fluid Mech.
484
, 69
(2003
).25.
D.
Bartolo
, C.
Josserand
, and D.
Bonn
, “Singular jets and bubbles in drop impact
,” Phys. Rev. Lett.
96
, 124501
(2006
).26.
L.
Chen
, L.
Li
, Z.
Li
, and K.
Zhang
, “Submillimeter-sized bubble entrapment and a high-speed jet emission during droplet impact on solid surfaces
,” Langmuir
33
, 7225
(2017
).27.
J.
Guo
, S.
Zou
, S.
Lin
, B.
Zhao
, X.
Deng
, and L.
Chen
, “Oblique droplet impact on superhydrophobic surfaces: Jets and bubbles
,” Phys. Fluids
32
, 122112
(2020
).28.
L.
Chen
, E.
Bonaccurso
, P.
Deng
, and H.
Zhang
, “Droplet impact on soft viscoelastic surfaces
,” Phys. Rev. E
94
, 063117
(2016
).29.
L.
Chen
and Z.
Li
, “Bouncing droplets on nonsuperhydrophobic surfaces
,” Phys. Rev. E
82
, 016308
(2010
).30.
S.
Mitra
, Q.
Vo
, and T.
Tran
, “Bouncing-to-wetting transition of water droplets impacting soft solids
,” Soft Matter
17
, 5969
(2021
).31.
S.
Gekle
, J. M.
Gordillo
, D.
van der Meer
, and D.
Lohse
, “High-speed jet formation after solid object impact
,” Phys. Rev. Lett.
102
, 034502
(2009
).32.
Y. H.
Liu
, L.
Moevius
, X. P.
Xu
, T. Z.
Qian
, J. M.
Yeomans
, and Z. K.
Wang
, “Pancake bouncing on superhydrophobic surfaces
,” Nat. Phys.
10
, 515
(2014
).33.
W.
Zhao
, S.
Lin
, L.
Chen
, E. Q.
Li
, S. T.
Thoroddsen
, and M.-J.
Thoraval
, “Jetting from an impacting drop containing a particle
,” Phys. Fluids
32
, 011704
(2020
).34.
Y.
Shang
, Y.
Zhang
, Y.
Hou
, B.
Bai
, and X.
Zhong
, “Effects of surface subcooling on the spreading dynamics of an impact water droplet
,” Phys. Fluids
32
, 123309
(2020
).35.
R. E.
Pepper
, L.
Courbin
, and H. A.
Stone
, “Splashing on elastic membranes: The importance of early-time dynamics
,” Phys. Fluids
20
, 082103
(2008
).36.
H.
Zhang
, X.
Zhang
, X.
Yi
, F.
He
, F.
Niu
, and P.
Hao
, “Reversed role of liquid viscosity on drop splash
,” Phys. Fluids
33
, 052103
(2021
).37.
T. C.
de Goede
, A. M.
Moqaddam
, K. C. M.
Limpens
, S. A.
Kooij
, D.
Derome
, J.
Carmeliet
, N.
Shahidzadeh
, and D.
Bonn
, “Droplet impact of Newtonian fluids and blood on simple fabrics: Effect of fabric pore size and underlying substrate
,” Phys. Fluids
33
, 033308
(2021
).38.
F.
Yeganehdoust
, R.
Attarzadeh
, A.
Dolatabadi
, and I.
Karimfazli
, “A comparison of bioinspired slippery and superhydrophobic surfaces: Micro-droplet impact
,” Phys. Fluids
33
, 022105
(2021
).39.
40.
J.
Philippi
, P. Y.
Lagree
, and A.
Antkowiak
, “Drop impact on a solid surface: short-time self-similarity
,” J. Fluid Mech.
795
, 96
(2016
).41.
A.
Mongruel
, V.
Daru
, F.
Feuillebois
, and S.
Tabakova
, “Early post-impact time dynamics of viscous drops onto a solid dry surface
,” Phys. Fluids
21
, 032101
(2009
).42.
N.
Bremond
and E.
Villermaux
, “Atomization by jet impact
,” J. Fluid Mech.
549
, 273
(2006
).43.
J.
Eggers
, “Nonlinear dynamics and breakup of free-surface flows
,” Rev. Mod. Phys.
69
, 865
(1997
).44.
J.
Shinjo
and A.
Umemura
, “Simulation of liquid jet primary breakup: Dynamics of ligament and droplet formation
,” Int. J. Multiphase Flow
36
, 513
(2010
).45.
S. T.
Thoroddsen
, T. G.
Etoh
, K.
Takehara
, N.
Ootsuka
, and Y.
Hatsuki
, “The air bubble entrapped under a drop impacting on a solid surface
,” J. Fluid Mech.
545
, 203
(2005
).46.
S.
Lin
, D.
Wang
, L.
Zhang
, Y.
Jin
, Z.
Li
, E.
Bonaccurso
, Z.
You
, X.
Deng
, and L.
Chen
, “Macrodrop-impact-mediated fluid microdispensing
,” Adv. Sci.
8
, 2101331
(2021
).© 2021 Author(s). Published under an exclusive license by AIP Publishing.
2021
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