With a novel platform of bilayer polydimethylsiloxane microchannel formed by bifurcating junction, we aim to investigate droplet formation and fission in a multiphase system with complex three-dimensional (3D) structure and understand the variations in mechanism associated with droplet formation and fission in the microstructure between shear-thinning/Newtonian system versus Newtonian/Newtonian system. The investigation concentrates on shear-thinning fluid because it is one of the most ubiquitous rheological properties of non-Newtonian fluids. Sodium carboxymethyl cellulose (CMC) solution and silicone oil have been used as model fluids and numerical model has been established to characterize the shear-thinning effect in formation of CMC-in-oil emulsions, as well as breakup dynamics when droplets flow through 3D bifurcating junction. The droplet volume and generation rate have been compared between two systems at the same Weber number and capillary number. Variation in droplet fission has been found between two systems, demonstrating that the shear-thinning property and confining geometric boundaries significantly affect the deformation and breakup of each mother droplet into two daughter droplets at bifurcating junction. The understanding of the droplet fission in the novel microstructure will enable more versatile control over the emulsion formation and fission when non-Newtonian fluids are involved. The model systems in the study can be further developed to investigate the mechanical property of emulsion templated particles such as drug encapsulated microcapsules when they flow through complex media structures, such as blood capillaries or the porous tissue structure, which feature with bifurcating junction.

References

References
1.
Ren
,
Y.
,
Liu
,
Z.
, and
Shum
,
H. C.
,
2015
, “
Breakup Dynamics and Dripping-to-Jetting Transition in a Newtonian/Shear-Thinning Multiphase Microsystem
,”
Lab Chip
,
15
(
1
), pp.
121
134
.
2.
Roberts
,
C. C.
,
Rao
,
R. R.
,
Loewenberg
,
M.
,
Brooks
,
C. F.
,
Galambos
,
P.
,
Grillet
,
A. M.
, and
Nemer
,
M. B.
,
2012
, “
Comparison of Monodisperse Droplet Generation in Flow-Focusing Devices With Hydrophilic and Hydrophobic Surfaces
,”
Lab Chip
,
12
(
8
), pp.
1540
1547
.
3.
Wang
,
K.
,
Lu
,
Y. C.
,
Xu
,
J. H.
,
Tan
,
J.
, and
Luo
,
G. S.
,
2011
, “
Generation of Micromonodispersed Droplets and Bubbles in the Capillary Embedded T-Junction Microfluidic Devices
,”
AIChE J.
,
57
(
2
), pp.
299
306
.
4.
Couture
,
O.
,
Faivre
,
M.
,
Pannacci
,
N.
,
Babataheri
,
A.
,
Servois
,
V.
,
Tabeling
,
P.
, and
Tanter
,
M.
,
2011
, “
Ultrasound Internal Tattooing
,”
Med. Phys.
,
38
(
2
), pp.
1116
1123
.
5.
Mcclements
,
D. J.
,
2007
, “
Critical Review of Techniques and Methodologies for Characterization of Emulsion Stability
,”
Crit. Rev. Food Sci. Nutr.
,
47
(
7
), pp.
611
649
.
6.
Husny
,
J.
, and
Cooper-White
,
J. J.
,
2006
, “
The Effect of Elasticity on Drop Creation in T-Shaped Microchannels
,”
J. Non-Newtonian Fluid Mech.
,
137
(1–3), pp.
121
136
.
7.
Samie
,
M.
,
Salari
,
A.
, and
Shafii
,
M. B.
,
2013
, “
Breakup of Microdroplets in Asymmetric T Junctions
,”
Phys. Rev. E
,
87
(
5
), p.
053003
.
8.
Menech
,
M. D.
,
2006
, “
Modeling of Droplet Breakup in a Microfluidic T-Shaped Junction With a Phase-Field Model
,”
Phys. Rev. E
,
73
(
3
), p.
031505
.
9.
Ting
,
T. H.
,
Yap
,
Y. F.
,
Nguyen
,
N. T.
,
Wong
,
T. N.
,
Chai
,
J. C. K.
, and
Yobas
,
L.
,
2006
, “
Thermally Mediated Breakup of Drops in Microchannels
,”
Appl. Phys. Lett.
,
89
(
23
), p.
234101
.
10.
Leshansky
,
A. M.
, and
Pismen
,
L. M.
,
2009
, “
Breakup of Drops in a Microfluidic T Junction
,”
Phys. Fluids
,
21
(
2
), p.
023303
.
11.
Nie
,
J.
, and
Kennedy
,
R. T.
,
2010
, “
Sampling From Nanoliter Plugs Via Asymmetrical Splitting of Segmented Flow
,”
Anal. Chem.
,
82
(
18
), pp.
7852
7856
.
12.
Menetrier-Deremble
,
L.
, and
Tabeling
,
P.
,
2006
, “
Droplet Breakup in Microfluidic Junctions of Arbitrary Angles
,”
Phys. Rev. E
,
74
(
3
), p.
035303
.
13.
Protiere
,
S.
,
Bazant
,
M. Z.
,
Weitz
,
D. A.
, and
Stone
,
H. A.
,
2010
, “
Droplet Breakup in Flow Past an Obstacle: A Capillary Instability Due to Permeability Variations
,”
EPL
,
92
(
5
), p.
54002
.
14.
Rosenfeld
,
L.
,
Fan
,
L.
,
Chen
,
Y.
,
Swoboda
,
R.
, and
Tang
,
S. K. Y.
,
2014
, “
Break-up of Droplets in a Concentrated Emulsion Flowing Through a Narrow Constriction
,”
Soft Matter
,
10
(
3
), pp.
421
430
.
15.
Link
,
D.
,
Anna
,
S.
,
Weitz
,
D. A.
, and
Stone
,
H. A.
,
2004
, “
Geometrically Mediated Breakup of Drops in Microfluidic Devices
,”
Phys. Rev. Lett.
,
92
(
5
), pp.
54503
54506
.
16.
Che
,
Z. Z.
,
Nguyen
,
N. T.
, and
Wong
,
T. N.
,
2011
, “
Hydrodynamically Mediated Breakup of Droplets in Microchannels
,”
Appl. Phys. Lett.
,
98
(5), p.
054102
.
17.
Cubaud
,
T.
,
2009
, “
Deformation and Breakup of High-Viscosity Droplets With Symmetric Microfluidic Cross Flows
,”
Phys. Rev. E
,
80
(
2
), p.
026307
.
18.
van Dinther
,
A. M. C.
,
Schroen
,
C. G. P. H.
, and
Boom
,
R. M.
,
2013
, “
Separation Process for Very Concentrated Emulsions and Suspensions in the Food Industry
,”
Innovative Food Sci. Emerging Technol.
,
18
, pp.
177
182
.
19.
Sang
,
L.
,
Hong
,
Y.
, and
Wang
,
F.
,
2009
, “
Investigation of Viscosity Effect on Droplet Formation in T-Shaped Microchannels by Numerical and Analytical Methods
,”
Microfluid. Nanofluid.
,
6
(
5
), pp.
621
635
.
20.
Tucker
,
C. L.
,
1989
,
Fundamental of Computer Modeling for Polymer Processing
,
Hanser Publishers
,
New York
.
21.
Hong
,
Y.
, and
Wang
,
F.
,
2007
, “
Flow Rate Effect on Droplet Control in a Co-Flow Microfluidic Device
,”
Microfluid. Nanofluid.
,
3
(
3
), pp.
341
346
.
22.
Benchabane
,
A.
, and
Bekkour
,
K.
,
2008
, “
Rheological Properties of Carboxymethyl Cellulose (CMC) Solutions
,”
Colloid. Polym. Sci.
,
286
(
10
), pp.
1173
1180
.
23.
Benyounes
,
K.
,
2013
, “
Investigation of the Influence of Molecular Weight of Polymer on the Rheological Behavior of Carboxylmethylcellulose Solutions
,”
13th SGEM GeoConference on Science and Technologies in Geology, Exploration and Mining
, June 16–22, pp.
951
958
.
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