This paper describes an investigation on the dynamic behavior of droplet formation in a microfluidic flow-focusing device (MFFD) under the effect of surfactant using a phase-field method and the Koterweg stress applied in Navier–Stokes equations. The effects of variously important parameters, such as capillary number (Ca0), water fraction (wf), the viscosity ratio (α), and particularly surfactant concentration (cb), were examined. Consequently, the numerical results match the experimental ones. Additionally, the droplet formation is significantly affected by the surfactant, and the droplet size decreases with increasing cb for the whole range of both wf and Ca0. Based on the extensive study, the phase diagrams with two main modes, namely, dropping and threading, are provided. A mountain shape of the dropping mode was found, and this mode can be extended for higher wf with the presence of surfactant. In particular, new generalized correlations as a function of wf, Ca0, and cb are first proposed for predicting quickly and effectively the droplet size. Furthermore, the droplet formation depends significantly on α. With the presence of surfactant, smaller size of the droplet forms and the threading mode occurs at very high α. The results obtained in this study are very useful for understanding the dynamic behavior of droplet formation in MFFDs, which can be used in potential applications such as biomedical and drug delivery systems.
References
1.
G.
Muschiolik
, “Multiple emulsions for food use
,” Curr. Opin. Colloid Interface Sci.
12
, 213
(2007
).2.
M.
Gallarate
, M. E.
Carlotti
, M.
Trotta
, and S.
Bovo
, “On the stability of ascorbic acid in emulsified systems for topical and cosmetic use
,” Int. J. Pharm.
188
, 233
(1999
).3.
Y.
Yamaguchi
, M.
Takenaga
, A.
Kitagawa
, Y.
Ogawa
, Y.
Mizushima
, and R.
Igarashi
, “Insulin-loaded biodegradable PLGA microcapsules: Initial burst release controlled by hydrophilic additives
,” J. Controlled Release
81
, 235
(2002
).4.
Y.
Liu
and X.
Jiang
, “Why microfluidics? Merits and trends in chemical synthesis
,” Lab Chip
17
, 3960
(2017
).5.
W.
Lee
, L. M.
Walker
, and S. L.
Anna
, “Role of geometry and fluid properties in droplet and thread formation processes in planar flow focussing
,” Phys. Fluids
21
, 032103
(2009
).6.
P.
Garstecki
, M. J.
Fuerstman
, H. A.
Stone
, and G. M.
Whitesides
, “Formation of droplets and bubbles in a microfluidic T-junction, scaling and mechanism of break-up
,” Lab Chip
6
, 437
(2006
).7.
G. F.
Christopher
, N. N.
Noharuddin
, J. A.
Taylor
, and S. L.
Anna
, “Experimental observations of the squeezing-to-dripping transition in T-shaped microfluidic junctions
,” Phys. Rev. E
78
, 036317
(2008
).8.
T.-D.
Dang
, Y. H.
Kim
, H. G.
Kim
, and G. M.
Kim
, “Preparation of monodisperse PEG hydrogel microparticles using a microfluidic flow-focusing device
,” J. Ind. Eng. Chem.
18
, 1308
(2012
).9.
T. D.
Dang
and S. W.
Joo
, “Preparation of tadpole-shaped calcium alginate microparticles with sphericity control
,” Colloids Surf., B
102
, 766
(2013
).10.
T.
Ward
, M.
Faivre
, M.
Abkarian
, and H. A.
Stone
, “Microfluidic flow focusing: Drop size and scaling in pressure versus flow-rate-driven pumping
,” Electrophoresis.
26
, 3716
(2005
).11.
M.
Mastiani
, S.
Seo
, S. M.
Jimenez
, N.
Petrozzi
, and M. M.
Kim
, “Flow regime mapping of aqueous two-phase system droplets in flow-focusing geometries
,” Colloids Surf., A
531
, 111
(2017
).12.
J.
Carneiro
, J. B. L. M.
Campos
, and J. M.
Miranda
, “PDMS microparticles produced in PDMS microchannels under the jetting regime for optimal optical suspensions
,” Colloids Surf., A
580
, 123737
(2019
).13.
J. H.
Xu
, S. W.
Li
, J.
Tan
, Y. J.
Wang
, and G. S.
Luo
, “Controllable preparation of monodisperse O/W and W/O emulsions in the same microfluidic device
,” Langmuir
22
, 7943
(2006
).14.
B.
Riechers
, F.
Maes
, E.
Akoury
, B.
Semin
, P.
Gruner
, and J.-C.
Baret
, “Surfactant adsorption kinetics in microfluidics
,” Proc. Natl. Acad. Sci. U. S. A.
113
, 11465
(2016
).15.
H.
Liu
and Y.
Zhang
, “Droplet formation in microfluidic cross-junctions
,” Phys. Fluids
23
, 082101
(2011
).16.
B.
Hoseinpour
and A.
Sarreshtehdari
, “Lattice Boltzmann simulation of droplets manipulation generated in lab-on-chip (LOC) microfluidic T-junction
,” J. Mol. Liq.
297
, 111736
(2020
).17.
I.-L.
Ngo
, T.-D.
Dang
, C.
Byon
, and S. W.
Joo
, “A numerical study on the dynamics of droplet formation in a microfluidic double T-junction
,” Biomicrofluidics
9
, 024107
(2015
).18.
I.-L.
Ngo
, S. W.
Joo
, and C.
Byon
, “Effects of junction angle and viscosity ratio on droplet formation in microfluidic cross-junction
,” J. Fluids Eng.
138
, 051202
(2016
).19.
G.
Yang
, X.
Chu
, V.
Vaikuntanathan
, S.
Wang
, J.
Wu
, B.
Weigand
, and A.
Terzis
, “Droplet mobilization at the walls of a microfluidic channel
,” Phys. Fluids
32
, 012004
(2020
).20.
M.
Besanjideh
, A.
Shamloo
, and S. K.
Hannani
, “Enhanced oil-in-water droplet generation in a T-junction microchannel using water-based nanofluids with shear-thinning bahavior: Anumerical study
,” Phys. Fluids
33
, 012007
(2021
).21.
I.
Chakraborty
, J.
Ricouvier
, P.
Yazhgur
, P.
Tabeling
, and A. M.
Leshansky
, “Droplet generation at Hele-Shaw microfluidic T-junction
,” Phys. Fluids
31
, 022010
(2019
).22.
W.
Han
, X.
Chen
, Z.
Wu
, and Y.
Zheng
, “Three-dimensional numerical simulation of droplet formation in a microfluidic flow-focusing device
,” J. Braz. Soc. Mech. Sci. Eng.
41
, 265
(2019
).23.
A. M.
Ibrahim
, J. I.
Padovani
, R. T.
Howe
, and Y. H.
Anis
, “Modeling of droplet generation in a microfluidic flow-fcusing junction for droplet size control
,” Micromachines
12
, 590
(2021
).24.
F.
Bai
, X.
He
, X.
Yang
, and R.
Zhou
, “Three dimensional phase-field investigation of droplet formation in microfluidic flow focusing devices with experimental validation
,” Int. J. Multiphase Flow
93
, 130
(2017
).25.
G.
Soligo
, A.
Roccon
, and A.
Soldati
, “Coalescence of surfactant-laden drops by phase field method
,” J. Comput. Phys.
376
, 1292
(2019
).26.
G.
Soligo
, A.
Roccon
, and A.
Soldati
, “Deformation of clean and surfactant-laden droplets in shear flow
,” Meccanica
55
, 371
(2020
).27.
A.
Riaud
, H.
Zhang
, X.
Wang
, K.
Wang
, and G.
Luo
, “Numerical study of surfactant dynamics during emulsification in a T-junction microchannel
,” Langmuir
34
, 4980
(2018
).28.
I. L.
Ngo
, T. K.
Lai
, H. J.
Choi
, H. T. T.
Le
, G. M.
Kim
, and T. D.
Dang
, “A study on mixing performance of dean flows through spiral micro-channel under various effects
,” Phys. Fluids
32
, 022004
(2020
).29.
F.
Magaletti
, F.
Picano
, M.
Chinappi
, L.
Marino
, and C. M.
Casciola
, “The sharp-interface limit of the Cahn–Hilliard/Navier–Stokes model for binary fluids
,” J. Fluid Mech.
714
, 95
(2013
).30.
G.
Soligo
, A.
Roccon
, and A.
Soldati
, “Mass-conservation-improved phase field methods for turbulent multiphase flow simulation
,” Acta Mech.
230
, 683
(2019
).31.
H.
Liu
and Y.
Zhang
, “Phase-field modeling droplet dynamics with soluble surfactants
,” J. Comput. Phys.
229
, 9166
(2010
).32.
COMSOL Multiphysics
, Fluid Flow and Chemical Species Transport Module, User and Theory Guide
(COMSOL Inc
., 2019
).33.
X.
Cheng
, T.
Glawdel
, N.
Cui
, and C. L.
Ren
, “Model of droplet generation in flow focusing generators operating in the squeezing regime
,” Microfluid. Nanofluid.
18
, 1341
(2015
).34.
S.
Bashir
, J. M.
Rees
, and W. B.
Zimmerman
, “Simulations of microfluidic droplet formation using the two-phase level set method
,” Chem. Eng. Sci.
66
, 4733
(2011
).35.
M. M.
Dupin
, I.
Halliday
, and C. M.
Care
, “Simulation of a microfluidic flow-focusing device
,” Phys. Rev. E
73
, 055701
(2006
).36.
A.
Shamloo
and M.
Hassani-Gangaraj
, “Investigating the effect of reagent parameters on the efficiency of cell lysis within droplets
,” Phys. Fluids
32
, 062002
(2020
).37.
A.
Gupta
, H. S.
Matharoo
, D.
Makkar
, and R.
Kumar
, “Droplet formation via squeezing mechanism in a microfluidic flow-focusing device
,” Comput. Fluids
100
, 218
(2014
).38.
M.
Rahimi
, S.
Yazdanparast
, and P.
Rezai
, “Parametric study of droplet size in an axisymmetric flow-focusing capillary device
,” Chin. J. Chem. Eng.
28
, 1016
(2020
).39.
A. M.
Leshansky
and L. M.
Pismen
, “Breakup of drops in a microfluidic T junction
,” Phys. Fluids
21
, 023303
(2009
).40.
S.
Arias
, D.
Legendre
, and R.
González-Cinca
, “Numerical simulation of bubble generation in a T-junction
,” Comput. Fluids
56
, 49
(2012
).41.
E.
Roumpea
, N. M.
Kovalchuk
, M.
Chinaud
, E.
Nowak
, M. J. H.
Simmons
, and P.
Angeli
, “Experimental studies on droplet formation in a flow-focusing microchannel in the presence of surfactants
,” Chem. Eng. Sci.
195
, 507
(2019
).42.
Z.
Liu
, M.
Chai
, X.
Chen
, S. H.
Hejazi
, and Y.
Li
, “Emulsification in a microfluidic flow-focusing device: Effect of the dispersed phase viscosity
,” Fuel
283
, 119229
(2021
).43.
N. M.
Kovalchuk
, E.
Roumpea
, E.
Nowak
, M.
Chinaud
, P.
Angeli
, and M. J. H.
Simmons
, “Effect of surfactant on emulsification in microchannels
,” Chem. Eng. Sci.
176
, 139
(2018
).44.
N.
Wu
, Y.
Zhu
, P.
Leech
, B.
Sexton
, S.
Brown
, and C.
Easton
, “Effects of surfactants on the formation of microdroplets in the flow focusing microfluidic device
,” Proc. SPIE
6799
, 67990C
(2007
).© 2022 Author(s). Published under an exclusive license by AIP Publishing.
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