Abstract

Potential use of Janus spheres in novel engineering applications is being explored actively in recent years. Hydrodynamics around Janus spheres is different from that around homogeneous sticky or slippery spheres. Instantaneous motion of a sphere in channel flow is governed by hydrodynamic force experienced by the sphere, which in turn depends on the particle to channel size ratio, its instantaneous position, hydrophobicity of its surface, and the particle Reynolds number. We investigate numerically the drag experienced by a Janus sphere located at different off-center positions in a square channel. Two orientations of Janus sphere consisting of a sticky and a slippery hemisphere with the boundary between them parallel to the channel midplane are studied: (1) slippery hemisphere facing the channel centerline and (2) sticky hemisphere facing the channel centerline. The flow field around Janus sphere is found to be steady (for Re ≤ 50 investigated in this work) and asymmetric. Based on the data obtained, a correlation for drag coefficient as a function of particle Reynolds number and dimensionless particle position is also proposed.

References

References
1.
Casagrande
,
C.
,
Fabre
,
P.
,
Veyssie
,
M.
, and
Raphael
,
E.
,
1989
, “
Janus Beads: Realization and Behaviour at Water/Oil Interfaces
,”
Europhys. Lett.
,
9
(
3
), pp.
251
255
.10.1209/0295-5075/9/3/011
2.
Synytska
,
A.
,
Khanum
,
R.
,
Ionov
,
L.
,
Cherif
,
C.
, and
Bellmann
,
C.
,
2011
, “
Water-Repellent Textile Via Decorating Fibers With Amphiphilic Janus Particles
,”
ACS Appl. Mater. Interfaces
,
3
(
4
), pp.
1216
1220
.10.1021/am200033u
3.
Nisisako
,
T.
,
Torii
,
T.
,
Takahashi
,
T.
, and
Takizawa
,
Y.
,
2006
, “
Synthesis of Monodisperse Bicolored Janus Particles With Electrical Anisotropy Using a Microfluidic Co-Flow System
,”
Adv. Mater.
,
18
(
9
), pp.
1152
1156
.10.1002/adma.200502431
4.
Zhang
,
J.
,
Zheng
,
X.
,
Cui
,
H.
, and
Silber-Li
,
Z.
,
2017
, “
The Self-Propulsion of the Spherical Pt–SiO2 Janus Micro-Motor
,”
Micromachines
,
8
(
4
), p.
123
.10.3390/mi8040123
5.
Haney
,
B.
,
Chen
,
D.
,
Cai
,
L.-H.
,
Weitz
,
D.
, and
Ramakrishnan
,
S.
,
2019
, “
Millimeter–Size Pickering Emulsions Stabilized With Janus Microparticles
,”
Langmuir
,
35
(
13
), pp.
4693
4701
.10.1021/acs.langmuir.9b00058
6.
Costantini
,
R.
,
Mollicone
,
J. P.
, and
Battista
,
F.
,
2018
, “
Drag Reduction Induced by Superhydrophobic Surfaces in Turbulent Pipe Flow
,”
Phys. Fluids
,
30
(
2
), p.
025102
.10.1063/1.5011805
7.
Dong
,
H.
,
Cheng
,
M.
,
Zhang
,
Y.
,
Wei
,
H.
, and
Shi
,
F.
,
2013
, “
Extraordinary Drag-Reducing Effect of a Superhydrophobic Coating on a Macroscopic Model Ship at High Speed
,”
J. Mater. Chem. A
,
1
(
19
), pp.
5886
5891
.10.1039/c3ta10225d
8.
Gruncell
,
B.
,
Sandham
,
N.
, and
Mchale
,
G.
,
2013
, “
Simulations of Laminar Flow Past a Superhydrophobic Sphere With Drag Reduction and Separation Delay
,”
Phys. Fluids
,
25
(
4
), p.
043601
.10.1063/1.4801450
9.
Vakarelski
,
I. U.
,
Chan
,
D. Y. C.
, and
Thoroddsen
,
S. T.
,
2014
, “
Leidenfrost Vapour Layer Moderation of the Drag Crisis and Trajectories of Superhydrophobic and Hydrophilic Spheres Falling in Water
,”
Soft Matter
,
10
(
31
), pp.
5662
5668
.10.1039/C4SM00368C
10.
Safaei
,
S.
,
Archereau
,
A.
,
Hendy
,
C. S.
, and
Willmott
,
R. G.
,
2019
, “
Molecular Dynamics Simulations of Janus Nanoparticles in a Fluid Flow
,”
Soft Matter
,
15
(
33
), pp.
6742
6752
.10.1039/C9SM00694J
11.
Das
,
S.
,
Garg
,
A.
,
Campbell
,
A. I.
,
Howse
,
J.
,
Sen
,
A.
,
Velegol
,
D.
,
Golestanian
,
R.
, and
Ebbens
,
S. J.
,
2015
, “
Boundaries Can Steer Active Janus Spheres
,”
Nat. Commun.
,
6
(
1
), p.
8999
.10.1038/ncomms9999
12.
Uspal
,
W. E.
,
Popescu
,
M. N.
,
Tasinkevych
,
M.
, and
Dietrich
,
S.
,
2018
, “
Shape-Dependent Guidance of Active Janus Particles by Chemically Patterned Surfaces
,”
New J. Phys.
,
20
(
1
), p.
015013
.10.1088/1367-2630/aa9f9f
13.
Sun
,
Q.
,
Klaseboer
,
E.
,
Khoo
,
B. C.
, and
Chan
,
D. Y.
,
2013
, “
Stokesian Dynamics of Pill Shaped Janus Particles With Stick and Slip Boundary Conditions
,”
Phys. Rev. E
,
87
, p.
43009
.10.1103/PhysRevE.87.043009
14.
Shklyaev
,
S.
,
Ivantsov
,
A.
,
Díaz-Maldonado
,
M.
, and
Córdova-Figueroa
,
U.
,
2013
, “
Dynamics of a Janus Drop in an External Flow
,”
Phys. Fluids
,
25
(
8
), p.
082105
.10.1063/1.4817541
15.
Swan
,
J.
, and
Khair
,
A.
,
2008
, “
On the Hydrodynamics of ‘Slip–Stick’ Spheres
,”
J. Fluid Mech.
,
606
, pp.
115
132
.10.1017/S0022112008001614
16.
Trofa
,
M.
,
D'Avino
,
G.
, and
Maffettone
,
P. L.
,
2019
, “
Numerical Simulations of a Stick-Slip Spherical Particle in Poiseuille Flow
,”
Phys. Fluids
,
31
(
8
), p.
083603
.10.1063/1.5109305
17.
Dhiman
,
M.
,
Ashutosh
,
S. A.
,
Gupta
,
R.
, and
Reddy
,
K. A.
,
2020
, “
Drag on Sticky and Janus (Slip-Stick) Spheres Confined in a Channel
,”
ASME. J. Fluids Eng.
,
142
(
7
), p.
071303
.10.1115/1.4046373
18.
Kempe
,
T.
,
Lennartz
,
M.
,
Schwarz
,
S.
, and
Fröhlich
,
J.
,
2015
, “
Imposing the Free-Slip Condition With a Continuous Forcing Immersed Boundary Method
,”
J. Comput. Phys.
,
282
, pp.
183
209
.10.1016/j.jcp.2014.11.015
19.
ANSYS
,
2019
, “
ANSYS Academic Research Fluent, Release 19.2, Help System, Theory Guide
,”
ANSYS Inc.
,
Canonsburg, PA
.
20.
Barth
,
T. J.
, and
Jespersen
,
D.
,
1989
, “
The Design and Application of Upwind Schemes on Unstructured Meshes
,”
AIAA
Paper No. 1989-366.10.2514/6.1989-366
21.
Issa
,
R. I.
,
1986
, “
Solution of Implicitly Discretized Fluid Flow Equations by Operator Splitting
,”
J. Comput. Phys.
,
62
(
1
), pp.
40
65
.10.1016/0021-9991(86)90099-9
22.
Rhie
,
M. C.
, and
Chow
,
W. L.
,
1983
, “
Numerical Study of the Turbulent Flow Past an Airfoil With Trailing Edge Separation
,”
AIAA J.
,
21
(
11
), pp.
1525
1532
.10.2514/3.8284
23.
Dhiman
,
M.
,
Gupta
,
R.
, and
Reddy
,
K. A.
,
2020
, “
Lift Forces on Stick and Janus Spheres in a Channel
,” Theor. Comput. Fluid Dyn., ePub.
You do not currently have access to this content.